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In this study, multiwalled carbon nanotube (MWCNT) anchored on the surface of silica coated porous rodlike nickel ferrite (NiFe 2 O 4 @SiO 2) composite was fabricated, and its structure, composition, magnetic and electromagnetic (EM) wave absorption properties were studied. High-performance EM wave absorption properties of the ternary composite can be regulated by the coating thickness and the content of the absorber. The reflection loss (RL) was optimized to −67.8 dB at the matching thickness of 1.9 mm, and the effective absorption bandwidth (RL ≤ −10 dB) was 4.5 GHz (13.5–18 GHz) at the coating thickness of only 1.5 mm with the filler loading 40 wt%. The effective bandwidth can reach 5.3 GHz (12.7–18 GHz) at the coating thickness of only 2.2 mm with the filler loading 30 wt%. The broadband absorption, thin thickness, strong absorption and adjustable absorption properties endow NiFe 2 O 4 @SiO 2 /MWCNT composite with extensive prospects for EM wave absorption. • Porous cubic-rodlike NiFe 2 O 4 @SiO 2 /MWCNT composite was successfully synthesized. • The effective bandwidth can reach 5.3 GHz at the absorber thickness of only 2.2 mm. • The reflection loss was optimized to −67.8 dB at the matching thickness of 1.9 mm. • The thickness and the filler loading have great effect on electromagnetic wave absorption properties. [ABSTRACT FROM AUTHOR]

Mechanically alloyed AlCoCrCuFeNi high-entropy alloy (HEA) powders were used as binder to fabricate WC/HEA composites by spark plasma sintering. The effects of sintering temperature, duration time and binder content on microstructures and mechanical properties were studied. Compared with cobalt binder, the HEA binder has an advantage on the inhibition of WC grain growth due to the sluggish diffusion effect, and the average WC grain size decreases with increasing HEA binder content. Furthermore, the fracture toughness of WC/HEA composites firstly increases with increasing Vickers hardness and then decreases. A good comprehensive mechanical property was obtained after sintering at 1250 °C for 5 min with 10 wt.% HEA binder under a sintering pressure of 30 MPa. The Vickers hardness is 1922 HV 30 and the fracture toughness is 10.41 MPa m 1/2 , which are higher than those of commercial WC/Co composites. Therefore, the AlCoCrCuFeNi high-entropy alloy has a potential to be a binder for WC. [ABSTRACT FROM AUTHOR]

A carbon/carbon (C/C)–Cu composite reinforced by novel carbon fiber 2.5D-braided preforms was fabricated through pressureless infiltration technique (PLI). The microstructure of the developed composite was characterized by scanning electron microscopy, X-ray diffraction, and energy dispersive spectroscopy. The mechanical, tribological, and electrical properties of the C/C–Cu composite were compared with those of a C/C composite and a carbon/copper (C/Cu) contact strip material. Results showed that the proposed composite formed an excellent network conduction structure. Moreover, the composite exhibited a high flexural strength of 215 MPa, excellent compression strength of 324 MPa, and a particularly low electrical resistivity of 0.63 μΩm, validating its advantages over the C/Cu composite strip in terms of mechanical and electrical properties. The component phases (TiC) of the C/C–Cu composite formed an excellent interconnected structure, which stiffened the interface between the Cu alloy and the pyrocarbon matrix and resulted in excellent mechanical and electrical properties. The friction coefficients of the C/C, C/C–Cu, and C/Cu composites were 0.152, 0.169, and 0.062, respectively. The C/Cu composite exhibited the worst mechanical and electrical performance despite achieving the lowest friction coefficient. Thus, the C/C–Cu composite is a promising new type of sliding electrical contact material. [ABSTRACT FROM AUTHOR]

(Zr 0.25 Hf 0.25 Ti 0.25 Ta 0.25)C high-entropy ceramics (ZHTTC) with exceptional compressive strength were prepared by spark plasma sintering at different temperatures (1900–2200 ℃). The effect of average grain size on compressive strength were investigated. The results indicate that the compressive strength degrades with the increase of the average grain size. The grain growth from 3.309 ± 0.603–9.25 ± 1.98 µm as the temperature elevated from 1900 to 2200 ℃. The ZHTTC-1900 achieves the maximum compressive strength of 3620 ± 180 MPa, while the compressive strength of ZHTTC-2200 is 1912 ± 203 MPa, which is 47 % lower than that of ZHTTC-1900. The increase of sintering temperature not only causes the increased average grain size, but also induces the decrease of grain boundary precipitation sites and adhesion of grain boundaries. The above reasons result in the degradation of compression properties. • ZHTTC-1900 with exceptional compressive strength of 3620 ± 180 MPa was achieved. • The segregation of Zr, Hf at the GB and grain refinement result in the exceptional compressive strength of ZHTTC-1900. • Effect of SPS conditions on grainsize was addressed, increased grainsize causes a 47 % decrease of compressive strength. [ABSTRACT FROM AUTHOR]

The green and facile synthesis of high performance anodes is of significant importance for development of lithium ion batteries (LIBs). Herein, a novel coordination chemistry-assisted method is demonstrated to successfully prepare a superior performance Fe 2 O 3 /C composite anode for LIBs. This method does not involve time-consuming pre-preparation of carbon materials and use of expensive sophisticated instruments and multiple harmful reagents, exhibiting relatively green and facile features over most of other methods. This Fe 2 O 3 /C composite consists of Fe 2 O 3 nanoparticles embedded in a porous carbon sheets assembled hierarchical matrix. Moreover, it finds that this beneficial architecture endows as-prepared Fe 2 O 3 /C with improved conductivity, enhanced kinetics, high capacitive contribution and good structure stability. In consequence, this Fe 2 O 3 /C anode exhibits superior electrochemical properties such as high capacity, long life and good rate performance, with 756.1 and 545.4 mA h g−1 after 200 cycles at 200 and 1000 mA g−1, respectively. The relatively ecofriendly and simple preparation process as well as superior electrochemical performance make this Fe 2 O 3 /C anode promising for LIB application. This work also offers a guiding significance for designing and developing ecofriendly and facile preparation methods of other metal oxides/carbon composites for advanced LIB anodes. [Display omitted] • A novel coordination chemistry-assisted method was used to prepare Fe 2 O 3 /C composite. • This method exhibited relatively green and facile features over other methods. • The effect of structure on lithium storage performance of Fe 2 O 3 /C was clarified. • The as-prepared Fe 2 O 3 /C showed superior performance as LIB anodes. • This work offered a guiding significance for preparing other metal oxide/carbon composite anodes. [ABSTRACT FROM AUTHOR]

YbFeO 3 exhibits spin switching (SSW) and spin reorientation transition (SRT) at low temperatures, but its mediocre magnetocaloric properties limit its further applications. As for TbFeO 3 showing a large magnetocaloric effect, its SSW is missing. Motivated by this, we chemically put Yb and Tb with a ratio of 1:3 on the rare-earth site. Potential applications of magnetic and magnetocaloric properties are both preserved in one single phase Yb 0.25 Tb 0.75 FeO 3 , which is exceptional among the rare-earth orthoferrites. Spin switching temperature (T SSW) in the field-cooled-cooling mode increases to around 100 K compared with YbFeO 3. A novel multiple SSW emerges in the field-cooled-warming mode originating from the complex competing magnetic interactions between Yb/Tb and Fe sublattices. We also addressed the mechanism of spin modification of magnetic ions with temperatures. Arrott plots created from the isothermal magnetization curves demonstrate that SRT is a second-order phase transition. The negative entropy change (refrigeration capacity) vs. temperatures [ − ∆ S m (RC) vs. T ] diagrams indicate that the − ∆ S m (RC) are effectively increased compared with YbFeO 3 by rare-earth doping. The pronounced magnetic refrigeration performance and SSW effect with a low-field dependence make it promising to be employed in both magnetic sensing and refrigeration devices. [Display omitted] ● The spin-switching effect appears in both cooling and warming mode. ● The multiple spin-switching effect are observed. ● The intronic mechanism of magnetic sublattices spin flipping is depicted. ● The giant magnetocaloric effect is observed. ● Magnetic refrigeration is highly improved compared with YbFeO 3. [ABSTRACT FROM AUTHOR]

The lead-free BiFeO 3 -BaTiO 3 (BF-BT) based ceramics with large piezoelectric coefficient (d 33) have been desired for promising applications in high-temperature fields. Herein, the 0.7Bi(Fe 0.9985 Mn 0.0015)O 3 -0.3BaTiO 3 ceramics with different grain sizes are intentionally prepared by solid-state method, and a large d 33 (232 pC/N) and high Curie temperature T c (501 °C) are simultaneously achieved in the case of large grain size (>9 µm). X-ray diffraction and Rietveld refinement analyses indicate that these coarse-grained samples possess stronger rhombohedral distortion and enlarged lattice parameter compared to fine-grained samples, which make domain switching easier and give rise to the increase in strain. As a result, the piezoelectric and ferroelectric properties of such samples are significantly improved with increasing grain size from 3.05 µm to 9.07 µm. In addition, electric domain configuration and field-induced strain further prove that the strong piezoelectric response in coarse-grained samples is attributed mainly to enhanced non-180° domain mobility. This study reveals the origin of large piezoelectric response in coarse-grained BF-BT ceramics, and proposes an effective approach to improve the piezoelectric properties of BF-BT ceramics. • High d 33 and T c are simultaneously achieved in BF-BT ceramic by adjusting grain size. • The origin of piezoelectric response in coarse-grained BF-BT ceramic is uncovered. • The effects of grain size on the electric properties of BF-BT ceramic are explored. [ABSTRACT FROM AUTHOR]

Supercapacitors based on flexible fabrics are considered promising wearable energy storage devices due to their skin adaptability and high mechanical properties. However, enhancing the electrical conductivity of flexible fabric substrates and optimizing the loading of active materials remains a challenge. Here, we propose a concept of functionalized ink interlayer to improve the performance of fabric-based supercapacitors. The functionalized ink interlayer not only has good electrical conductivity but also guides the loading of polyaniline (PANI) and facilitates charge transfer at the electrode/electrolyte interface, generating a synergistic effect with the active material. The areal capacitance (323.3 mF cm−2) of cotton fabric/conductive carbon oil/ink@PANI supercapacitor is greater than the sum (210.2 mF cm−2) of cotton fabric/conductive carbon oil/ink supercapacitor and cotton fabric/conductive carbon oil@PANI supercapacitor. Additionally, the maximum energy density of supercapacitor with ink interlayer is 28.5 μWh cm−2 and the maximum power density is 2057 μW cm−2. The electrode with ink interlayer can maintain a fast electrodynamic process and the cycling stability is also improved. Finally, interdigital and tree-like clothing appliques were prepared and sewn onto clothing to realize wearable energy storage function using ink@PANI-based electrodes. This work provides important references for the development of fabric-based supercapacitors. • A functionalized ink interlayer is proposed to prepare fabric-based supercapacitors. • The ink interlayer can regulate the loading of PANI and enhance the performance. • Conductivity and capacitance of fabric electrode are improved with ink interlayer. • Wearable energy devices are demonstrated based on ink-assisted fabric electrodes. [ABSTRACT FROM AUTHOR]

Ni2+ doped and Ni2+/Er3+ co-doped Gd 2 MgTiO 6 (GMT) phosphors have been synthesized by conventional high-temperature solid-state reaction method. First-principles calculation and X-ray diffraction analysis proves that Ni2+ ions occupy the Mg2+ sites in the Gd 2 MgTiO 6 matrix at low Ni2+ doping concentration and begin to occupy Ti4+ sites at high Ni2+ doping concentration. The near infrared emissions of Ni2+ ions occupying Mg2+ and Ti4+ sites peak at 1344 nm and 1412 nm, respectively, forming a broad near infrared emission band from 1100 nm to 1700 nm. It is found that Ni2+/Er3+ co-doped Gd 2 MgTiO 6 phosphor is capable to up-convert near infrared photons in the wavelength range of 870–1700 nm to visible 532 nm, 555 nm and 666 nm emission, caused by the energy transfer sensitization process from Ni2+ to Er3+. The Ni2+ and Er3+ concentration dependent up-conversion properties have been investigated and it is found that the Gd 2 MgTiO 6 : 2%Ni2+/5%Er3+ phosphor shows the strongest up-conversion emission, in which the energy transfer efficiencies from the Ni2+ ions occupying Mg2+ and Ti4+ sites to the Er3+ ions are 81.5% and 79.3%, respectively. The Gd 2 MgTiO 6 : 2%Ni2+/5%Er3+ phosphor shows yellow emission under the irradiation of 1342 nm and 1550 nm lasers, and green and orange-red emissions under the irradiation of 980 nm and 1064 nm laser, respectively. The broad band excitability and multi-color up-conversion performance of the Ni2+/Er3+ co-doped Gd 2 MgTiO 6 phosphor suggest that it has wide application prospect in anti-counterfeiting, solar cell efficiency enhancement, infrared detection and so on. • Broadband near infrared emission of Ni2+ is firstly witnessed in Gd 2 MgTiO 6. • Gd 2 MgTiO 6 : Ni2+/Er3+ can up-convert 900–1700 nm light into visible emission. • Ni2+→Er3+ energy transfer and Er3+ excited absorption performs the up-conversion. • The phosphor shows different up-conversion color excited at different wavelength. [ABSTRACT FROM AUTHOR]

Rutile TiO 2 is a competitive white pigment due to its high refractive index and inertness. Uncolored Mg2+ is a promising dopant for the production of TiO 2 pigment because it promotes the anatase-to-rutile phase transition of TiO 2 at lower temperatures (vs. Al3+). However, research on the impact of Mg2+ concentration on TiO 2 phase transition is scarce, and the defect structures are still unknown. In this study, the effect of Mg2+ doping concentration on TiO 2 phase transition was investigated, and the defect structures of Mg2+ doped TiO 2 were proposed. Over 96% conversion of anatase to rutile was achieved with 1.48% Mg doping at 875 °C (vs. Al3+, 1050 °C) for 1 h. By using the Rietveld method, two defect structures—interstitial Mg2+ (Mg int) and substitute Mg2+ (Mg sub)—were quantified. A correlation between the defect structures and the effect on phase transition was established. At low Mg doping level (<1%), the Mg int dominates and weakly promotes the phase transition; At high Mg doping level (>1%), the Mg sub dominates and strongly promotes the phase transition. Additionally, a possible mechanism for the formation of defect structures and how that affects phase transition was proposed. The present results may provide insights into TiO 2 pigment production and modulation of TiO 2 defects for phase transition control and other applications. • 96% conversion of anatase to rutile was achieved at 875 °C (1050 °C in industry). • The two defect structures of Mg2+ doped TiO 2 —interstitial Mg2+ and substitute Mg2+—were quantified by Rietveld method. • The correlation between defect structures and phase transition is established. • The possible mechanism for the formation of defect structures and how that affects phase transition was proposed. [ABSTRACT FROM AUTHOR]

In this study, a novel rare-earth element-free Mg–Bi–Sn–Mn alloy system (with Bi and Sn as double principal elements) was developed to overcome the applicability limitations of Mg alloys while avoiding the use of rare-earth elements. The characteristics of the precipitates and creep performance of a peak-aged Mg–5Bi–5Sn–0.5Mn (BTM550) alloy were investigated. The results indicated an unexpected deterioration in the creep properties of the rare-earth element-free alloy after peak-aging treatment. This is primarily due to the change in the orientation relationships (ORs) of numerous static and dynamic precipitates (containing Mg 2 Sn and Mg 3 Bi 2) to a basal plane orientation that has a limited ability to block dislocations. The ORs of Mg 2 Sn and Mg 3 Bi 2 precipitates with the matrix are (022) Mg2Sn //(0002) Mg , [01-1] Mg2Sn //[1−210] Mg and (10−10) Mg3Bi2 //(0001) Mg , [0001] Mg3Bi2 //[1−210] Mg , respectively. Both, submicron Mg 2 Sn and Mg 3 Bi 2 precipitates, exert equivalent effects on the deterioration of the creep properties. Additionally, based on the calculated stress exponent values and transmission electron microscopy results, we determined that the creep process is controlled by cross-slip in the peak-aged BTM550 alloy. [ABSTRACT FROM AUTHOR]

As typical energy storage devices, the extensive application of the supercapacitors is largely restricted by their relatively low energy storage efficiency, which motivates the development of various advanced electrode materials with sophisticated architectural design. Herein, we put forward a robust and controllable approach to construct a series of hybrid nanoarchitectures consisting of nanoflower-shaped MnO 2 nanocrystals grown on super-thin Ti 3 C 2 T x MXene nanosheets (MNF/Ti 3 C 2 T x) via a convenient co-precipitation process. Such a delicate configuration enables the nanoarchitectures to provide prominent structural merits, such as 2D thin-sheet structure with large surface area, porous MnO 2 nanoflower frameworks, activated electronic structure, and high electron conductivity. As a consequence, the optimized MNF/Ti 3 C 2 T x electrode manifests superior electrochemical capacitive properties with a maximum specific capacitance of 348.5 F g−1 at 0.5 A g−1, excellent rate property, and reliable cycling stability with 91.9% retention of initial capacitance after 5000 cycles, all of which are more competitive than those of conventional MnO 2 and Ti 3 C 2 T x electrodes. [Display omitted] • The stereoassembly of ε-MnO 2 nanoflowers on 2D Ti 3 C 2 T x MXene nanosheets is achieved. • MXene nanosheets are able to optimize the electronic and geometric structures of MnO 2. • The nanoflower-shaped MnO 2 affords numerous accessible electrochemically active sites. • The derived nanoarchitectures are expected to serve as promising electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

With the development of electronic products to miniaturization and high frequency, high-performance flexible electromagnetic interference (EMI) shielding materials are urgently needed to deal with electromagnetic pollution. Two-dimensional transition metal carbide/polyimide (Ti 3 C 2 T x MXene/PI) films were synthesized by in situ polymerization and a simple scratch method in this paper. The Ti 3 C 2 T x MXene nanosheets give the films good EMI shielding effectiveness (SE) and electrical conductivity. Specifically, the film with a thickness of 0.11 mm (Ti 3 C 2 T x content of 30 wt%) exhibits an EMI SE of 34.73 dB and a specific EMI SE (SE/thickness) of 315.73 dB/mm in the frequency range of 8.2–12.4 GHz (X-band). In addition, the films have a tensile strength of 67.58 MPa, and a high decomposition temperature of 510 ℃ in N 2 atmosphere. Therefore, we believe that the prepared Ti 3 C 2 T x /PI films with good comprehensive performance have enormous potential in the field of lightweight and flexible EMI shielding materials. • Ti 3 C 2 T x MXene/Polyimide composites film was synthesized by in situ polymerization and scraping method. • With the increase of Ti 3 C 2 T x MXene content, the electrical conductivity and EMI SE of the films increased. • The films exhibit good flexibility and tensile properties. • The film with thickness of 0.11 mm exhibited 34.73 dB EMI SE when Ti 3 C 2 T x MXene was added at 30 wt%. [ABSTRACT FROM AUTHOR]

Lithium-metal batteries (LMBs) have attracted special interest owing to their high energy densities. Nevertheless, the unfavorable reactivity of lithium metal (Li metal) leads to the uncontrolled growth of dendrites and formation of unstable solid electrolyte interlayers, which shorten the cycle life of Li metal and limit its wide application. Herein, a conformal and thin protective layer, composed of Sn, an Sn–Li alloy, lithium fluoride (LiF), and polyethylene oxide (PEO) (denoted as Li-Sn-LiF@PEO), is constructed in situ on Li metal via a facile one-step method. This conformal artificial layer not only reduced the subsequent surface reactions of lithium with the electrolytes, but also effectively accommodated the large volume change of the Li-metal anode and suppressed the growth of Li dendrites. Symmetric cells with Li-Sn-LiPEO-modified Li-metal anodes exhibited small voltage hysteresis and outstanding plating/stripping cyclability over 400 h at high current densities and capacities of 20 mA cm−2 and 20 mAh cm−2. When coupled with NCA/NCM523/LiFePO 4 cathodes, the corresponding LMBs exhibited remarkable cycling life and superior rate properties. These encouraging results demonstrate a novel and promising method for long-life and large-scale stable LMBs. [Display omitted] • A conformal and thin protective layer for the Li metal anode is synthesized. • The Li-Sn-LiF@PEO coating layer suppresses the Li dendrite growth effectively. • The modified Li shows good cyclability over 400 h at 20 mA cm−2 and 20 mAh cm−1. • The constructed LMBs achieve superior rate capability and long cycle life. [ABSTRACT FROM AUTHOR]

Tetragonal BaTiO 3 (BT) powder with appropriate size and dispersity is essential for the dielectric layers in multilayer ceramic capacitor technology. In this work, high tetragonality BT powder with controllable dispersion, and particle size was synthesized using combined dispersants and a two-step hydrothermal method. Owing to the synergistic effect of chemical bond force and electrostatic adsorption force between cetyltrimethylammonium bromide (CTAB) and polyvinyl-pyrrolidone (PVP) composite dispersants at a high temperature, the ultrafine BT powder with a high c/a of 1.0090, small size of 236 ± 15 nm and low polydispersity index of 0.336 was achieved. This idea shows great significance for the synthesis of BT powder with high tetragonal, high dispersion, and small particle sizes. • High tetragonality BT powder with controllable dispersion, and particle size was synthesized using combined dispersants and a two-step hydrothermal method. [ABSTRACT FROM AUTHOR]

Mechanical alloying was performed in a planetary ball mill by using a rotational speed of 400 r/min and a ball to powder ratio of 20:1 at room temperature. Milling was performed for 5, 15, 25, 36, and 45 h. The effect of milling time on the microstructure and properties of alloy powders, microstructure of W–Nb alloys, and second-phase distribution were studied through field-emission scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray diffraction analyses. Results showed that crystalline size, lattice strain, and dislocation density significantly changed when the milling time was increased from 5 h to 25 h. Further increase in the milling time slightly influenced the parameters. W–Nb alloy powders exhibited the lowest lattice parameters after 25 h of milling. Among the formed W–Nb solid solutions, W–Nb alloy milled for 25 h exhibited the lowest porosity and contained homogenously and finely distributed Nb-rich phases in the tungsten grains and boundaries. Thermal desorption spectroscopy analysis was also performed to assess deuterium retention after irradiation. Based on the total amount of deuterium in the W–Nb alloys, those milled for 25 h exhibited the optimal irradiation resistance. In conclusion, 25 h is the optimal milling time for mechanical manufacture of W–Nb alloys. [ABSTRACT FROM AUTHOR]

A series of novel Li 1/3 Sr 1/3 Eu 1/3 MoO 4 phosphors have been fabricated via the conventional ceramic processing route at different sintering temperatures. The crystal structure, morphology and luminescent properties of the as-synthesized phosphors were characterized through X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) and photoluminescence (PL), respectively. It is found that the sintering temperature has significant influences on the crystallinity, morphology and luminescent properties of the obtained Li 1/3 Sr 1/3 Eu 1/3 MoO 4 phosphors. In the selected sintering temperature range (600–1000 °C), all the obtained Li 1/3 Sr 1/3 Eu 1/3 MoO 4 phosphors possess tetragonal scheelite structure, the synthesized phosphors changed gradually from quasi-spherical to polyhedral particles with a size of 1.0–5.0 μm. All the as-synthesized Li 1/3 Sr 1/3 Eu 1/3 MoO 4 samples are typical red-emission phosphors, which can emit 591 nm and 615 nm red light under the excitation of 393 nm ultraviolet and 464 nm blue light, respectively. Moreover, the emission intensities of the phosphors firstly increase and then decrease with increasing sintering temperature, reaching the maximum at 800 °C. All the obtained Li 1/3 Sr 1/3 Eu 1/3 MoO 4 phosphors displayed a pure red emission, which are promising red phosphors. Image 1 • A novel Li 1/3 Sr 1/3 Eu 1/3 MoO 4 red phosphor system has been proposed and fabricated. • The effects of sintering temperatures on microstructures and luminescence properties have been investigated. • The as-fabricated Li 1/3 Sr 1/3 Eu 1/3 MoO 4 red phosphor at 800 °C presents the superior luminescent properties. [ABSTRACT FROM AUTHOR]

Fine-grained processing of Inconel 617 sheet was proposed, and microstructural evolution during processing was analyzed. The optimum recovery temperature at 750 °C and the best recrystallization annealing temperature at 1000 °C were determined by experiments. The optimal fine-grained process comprised heat treatment (750 °C × 1 h), first cold rolling (60% reduction rate), high-temperature recovery (750 °C × 1 h), second cold rolling (10% reduction rate), and recrystallization annealing (1000 °C × 3 h). After recrystallization annealing (1000 °C × 3 h), the fine-grained sheet consisted of equiaxed grains with a size of 4–6 μm. A high proportion of high-angle grain boundaries was observed, and most of the grain orientation spread values were less than 1. The grain recrystallized completely. Twin refinement mechanism played a dominant role in sheet grain refinement. The hardness and tensile mechanical properties of the fine-grained sheet were notably stronger than those of the original sheet. • A new grain refinement process for an Inconel 617 sheet was proposed. • A fine-grained sheet with an average grain size of 4–6 μm was prepared. • Fine-grained sheet was analyzed by EBSD. [ABSTRACT FROM AUTHOR]

Developing an alternative solution to reduce or not use the rare-earth ions is of much importance. Tunable up-conversion (UC) multicolor luminescence is realized by utilizing the green UC emission of the intrinsic defects and optimizing the doping contents of Yb3+ and Tm3+ ions in the Na 0.5 Bi 0.5- x - y Yb x Tm y TiO 3 (NBT: x Yb/ y Tm) ceramics. The UC white-light emission, which is close to the standard achromatic point, is achieved by an optimal design. And the possible up-conversion emission mechanism of defects and Tm3+/Yb3+ ions is also discussed. In addition, the optical temperature sensing properties were also investigated basing on the UC emission of defects in a temperature range from 83 to 683 K. The results indicate that the NBT: x Yb/ y Tm is promising for the application as optical thermometry materials. • A strong UC luminescence is realized based on the intrinsic defects. • UC white-light emission is achieved by an optimal design. • Optical temperature sensing properties are obtained in the ceramics. • The ceramics can be applied in electrical/optical interdisciplinary field. [ABSTRACT FROM AUTHOR]

In this work, nominal composition (1-x)BaTiO 3 -xBi(Zn 0.5 Y 0.5)O 2.75 [abbreviated as (1-x)BT-xBZY, (x = 0.05, 0.1, 0.15, 0.2, 0.25)] ceramics were prepared by solid-state reaction method, and sintered in reducing atmosphere. Effect of introducing BZY on the structure, dielectric and insulating properties of BT was investigated. XRD results demonstrated that the unit cell volume of (1-x)BT-xBZY ceramics expanded with the addition of BZY, accompanied with the transformation from tetragonal to pseudo-cubic phase when x ≥ 0.05. Electrical properties measurement showed that the dielectric-temperature stability and insulating properties of (1-x)BT-xBZY ceramics were effectively improved by BZY addition, where the optimum performances were achieved at x = 0.15, with the dielectric constant of 1362 and dielectric loss of 1.4%, and resistivity of 5.5 × 1012 Ω cm at room temperature, meeting the standard of X8R specification for MLCC application. The feasible mechanism of improved anti-reduction properties for (1-x)BT-xBZY ceramics was investigated by employing X-ray photoelectron spectra (XPS) and thermally stimulated depolarization current (TSDC) testing techniques, where the formation of defect dipoles [2Y Ti ˈ - V O.. ] and the deoxidation of Bi ion were revealed and considered to be responsible for the anti-reduction behavior. • (1-x)BT-xBZY ceramics were sintered in reducing atmosphere. • X8R ceramics with excellent insulation performances were achieved. • Anti-reduction mechanism were comprehensively investigated. • Defect structures inside the ceramic were identified. • Defective dipoles beneficial to the anti-reduction properties of BT-BZY ceramics. [ABSTRACT FROM AUTHOR]

In this study, Phosphorus-doped mesoporous graphitic carbon nitride (P-mpg-C 3 N 4) was successfully prepared by a facile simple thermal method. Microstructure and chemical properties of catalyst were studied by a series of characterization methods, the results showed that the P atoms were successfully doped on the structure of graphitic carbon nitride and uniformly distributed on the whole mesoporous nanostructure. And specific surface area of P-mpg-C 3 N 4 can reach 198.3 m2/g, which is almost 10.7 times more than that of g-C 3 N 4 (18.6 m2/g), pore diameter of P-mpg-C 3 N 4 is mainly distributed in 2–20 nm and the average pore size is 11.3 nm. Photocatalytic degradation performance of the catalyst for brilliant ponceau 5R (BP-5R) in solution were studied under dark and visible light irradiation. The photocatalytic activity of P-mpg-C 3 N 4 is about 31.1 times higher compared with that of g-C 3 N 4 , and about 3.9 times and 2.4 times than that of mpg-C 3 N 4 and P-g-C 3 N 4 , respectively. Mechanism of its enhanced photocatalytic performance was mainly attributed to the synergistic effect of P-doping and fragmented mesoporous structure, on the one hand, which can extend visible light absorption range. On the other hand, it's can also promote the separation of photo-generated electron-hole pairs and accelerate the transfer of photo-generated electrons. Image 1 • A novel material was synthesized as semiconductors photocatalyst. • The catalysts have excellent degradation efficiency of BP-5R dye. • The catalyst still remains a high stability and good repeatability after cycles. • Superoxide radicals (O 2 −) and holes (h+) are the main active species. • The degradation rate by P-mpg-C 3 N 4 is 31.1 times higher than that of g-C 3 N 4. [ABSTRACT FROM AUTHOR]

Ultrafine WC cemented carbides with 10 wt% mechanically alloyed Al x CoCrCuFeNi (x is the aluminium content in molar ratio and ranges from 0 to 1.5) high-entropy alloy (HEA) binders were fabricated by spark plasma sintering. The influences of the HEA binders on the microstructures and mechanical properties of WC-HEA cemented carbides were discussed. Due to the sluggish diffusion effect of the HEA binders, the WC grain growth activation energy of WC-HEA cemented carbides is significantly higher than that of WC-Co alloy. Consequently, the grain growth of WC is inhibited during sintering, and an ultrafine microstructure can be obtained. With increasing Al content of HEA binders, both the relative density of WC-HEA cemented carbides and the hardness of HEA binders increase, which contributes to the high hardness of WC-HEA cemented carbides. The fracture toughness of WC-HEA cemented carbides is codetermined by the wettability of HEAs on WC and the intrinsic sintering property and deformability of HEA binders. Therefore, the WC-HEA cemented carbide with 10 wt% Al 0.5 CoCrCuFeNi high-entropy alloy binder exhibits the best combination of Vickers hardness and fracture toughness, which are 2071 ± 6 HV 30 and 10.3 ± 0.1 MPa m1/2, respectively. • Ultrafine WC-HEA composites without grain growth inhibitor were fabricated by SPS. • The component of HEA binder strongly affected WC grain growth activation energy. • Effects of HEA binders on mechanical properties of WC-HEA composites were studied. [ABSTRACT FROM AUTHOR]

SiC fiber reinforced mullite matrix (SiC f /Mu) composites were prepared via an infiltration and sintering process using SiC and Ti 3 SiC 2 as inert fillers. The effects of SiC and Ti 3 SiC 2 fillers on microstructure, mechanical, dielectric and microwave absorption properties of the composites were studied. The composite with 15 wt% SiC filler obtained a flexural strength of 300 MPa. The complex permittivity of the composite was enhanced from 12.3−j22.1 to 14.2−j39.7 at 10 GHz when the Ti 3 SiC 2 content increased from 10 wt% to 30 wt%. By adding 15 wt% SiC and 10 wt% Ti 3 SiC 2 in the matrix, both mechanical and microwave absorption properties of the SiC f /Mu composites were significantly improved. A flexural strength of 292 MPa and a failure displacement of 0.47 mm were obtained for the composite with hybrid SiC/Ti 3 SiC 2 fillers. The composite with a thickness of 2.9 mm obtained an effective absorption bandwidth of 3.3 GHz (from 9 to 12.3 GHz), with a minimum reflection loss of −53 dB at 8.64 GHz. Results indicated that the SiC f /Mu composite with hybrid SiC/Ti 3 SiC 2 fillers was one of the excellent structural-functional candidates for military application. • The composite with hybrid SiC/Ti 3 SiC 2 fillers possesses excellent properties. • The flexural strength and failure displacement are 292 MPa and 0.47 mm. • An effective absorption bandwidth of 3.3 GHz (from 9 to 12.3 GHz) is obtained. • A minimum reflection loss of −53 dB at 8.64 GHz is obtained. [ABSTRACT FROM AUTHOR]

Hypereutectic Al-Fe alloys are extremely brittle owing to the formation of coarse Fe-rich intermetallics in the Al matrix. In this study, a Ce-rich rare-earth (RE) mixture was introduced to modify an Al-5Fe binary alloy, and the crystallization, microstructure, and mechanical properties of the alloy were investigated. The experimental results indicated that the RE addition decreased the temperature of the primary Al 3 Fe phase, enhanced the temperature of the eutectic transformation, and disturbed the normal crystallization process of eutectic α-Al crystals by decreasing the intrinsic growth along the preferential close-packed (111) Al plane and promoting the growths depending on the sub-closed (200) Al plane. Furthermore, RE addition refined the primary Al 3 Fe phases and formed Al-Ce eutectics in the as-cast state of the alloy. Fine nodules and rods of the Al 4 Ce and AlCe phases containing La elements were produced through homogeneous annealing via the decomposition of the Al-Ce eutectics and precipitation of REs from the RE-enriched area. Rolling further broke up the coarser primary Al 3 Fe phases into short rods and particles and caused the Al-Ce and Al-Fe phases to become uniformly distributed in the Al matrix. A mixed cleavage and dimple fracture was produced by RE modification, annealing, and rolling. The optimized amount of added RE mixture for improving the microstructure and mechanical properties of the alloy was 0.9 wt%. • RE addition decreased the primary temperature of Al 3 Fe phase. • RE addition inhibited intrinsic growth of eutectic α-Al along (111) plane. • RE addition promoted the growth of eutectic α-Al along sub-closed (200) plane. • RE addition refined primary Al 3 Fe phases and formed Al-Ce eutectics. • 0.9 wt% RE was optimized for improving microstructure and mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract A large electrostrain usually occurs at ferroelectric-ferroelectric phase boundaries. However, in the Ba(Ti 1 – x Zr x)O 3 (BT- x Zr) system prepared by the conventional solid-state reaction method, we discovered a local electrostrain maximum in the single rhombohedral phase region at the quasi-quadruple point with a composition of BT-0.12Zr that had a relatively weak temperature sensitivity below 50 °C. Mechanisms of the local electrostrain maximum in the single-phase region of the BT- x Zr system were studied. The large coercive field and large domain size of BT-0.12Zr indicate that domain switching was not facilitated. Nevertheless, the large lattice distortion of BT-0.12Zr suggests a large intrinsic lattice strain, which predominantly contributed to the observed macroscopic electrostrain enhancement at the quasi-quadruple point composition in the single-phase region. Compared to nearby sample compositions, the largest lattice distortion of BT-0.12Zr was found to be correlated with the highest electrostrictive coefficient at the tricritical quasi-quadruple point, as deduced from phenomenological Landau analysis. Our work may shed light on the development of weakly temperature-dependent large electrostrain materials by identifying the tricritical quasi-quadruple point in ferroelectric phase diagrams. Graphical abstract Image 1 Highlights • Ba(Ti 0.88 Zr 0.12)O 3 shows high electrostrain in single rhombohedral phase region. • The enhanced strain in single phase exhibits relatively good temperature stability. • The effect stems from the highest electrostrictive coefficient of quadruple point. • Our finding provides a method to design temperature-stable, high-strain materials. [ABSTRACT FROM AUTHOR]

Abstract The magnetocaloric effect and magnetoresistance (MR) of nanocrystalline/amorphous Gd 65 Co 15 Al 10 Zr 10 alloy were investigated. The as-spun alloy shows a large maximum magnetic entropy change (MEC) of 5.4 Jkg−1K−1 under a field change of 5 T and a refrigerant capacity of 468.9 Jkg-1. It is found that Ar ion irradiation increases the MEC and refrigerant capacity (RC) of the alloy, which is associated with the anisotropic stress and heating effects, increasing the atomic mobility and short-range order around Gd. Moreover, the maximum MEC shows a power-law (linear) relationship with the MR above (below) the Curie temperature for the as-spun ribbon, which alters after irradiation. Highlights • Ar ion irradiation increases the magnetocaloric effect (MCE) of Gd 65 Co 15 Al 10 Zr 10 alloy. • The improvement of MCE is associated with the anisotropic stress and heating effects. • The maximum MCE shows a power-law (linear) relationship with the MR above (below) the Curie temperature for the sample. [ABSTRACT FROM AUTHOR]

Abstract P 2 O 5 -added Li 2 O-SiO 2 -Si 3 N 4 glasses were prepared by melt-quenching the liquid inside a glove box under a N 2 atmosphere. Studies on crystallization kinetics of the glasses show that the crystallization of oxynitride glasses is controlled by the three-dimensional interfacial growth mode of crystals (Avrami index = 2.70–3.90). The introduction of the nucleating agent P 2 O 5 can increase the crystallization ability, and the crystallization activation energy is reduced. X-ray diffraction and scanning electron microscope were used to investigate the crystallization behavior and phase formation of the glass-ceramics. In general, the addition of 3.0 mol% nucleating agent P 2 O 5 and two-step heat-treatment facilitate the precipitation of rod-like Li 2 Si 2 O 5 crystals with high aspect-ratio, which are uniformly embedded in the glass matrix and show interlocking and uniform morphology, thereby improving the mechanical properties of Li 2 O-SiO 2 -Si 3 N 4 oxynitride glass-ceramics. This work provides a roadmap for the preparation of high performance glass-ceramics. Highlights • Crystallization kinetics study show three-dimensional interfacial growth mode for glasses. • P 2 O 5 can act as effective nucleating agent to promote crystallization of oxynitride glass. • Rod-like Li 2 Si 2 O 5 with high-aspect-ratio contribute to improvement of bending strength. • This work provides a roadmap for the preparation of high properties glass-ceramics. [ABSTRACT FROM AUTHOR]

Abstract To recycle the solid waste coal fly ash (CFA), a new approach of adding Ni-coated coal fly ash (Ni-CFA) to waterborne inorganic zinc-rich coatings (ZRCs) was proposed. The effect of Ni-CFA on the corrosion resistance of ZRCs was investigated systematically using open-circuit potential (OCP) measurements, the DC polarization technique and electrochemical impedance spectroscopy (EIS). The results showed that the addition of 6.6 wt% Ni-CFA noticeably improved the cathodic protection of the coating due to the electrical conductivity of the Ni layer and decreased the corrosion current when providing barrier protection. Meanwhile, the active SiO 2 on the surface of CFA was found to increase the degree of cross-linking of the potassium silicate, resulting in better mechanical properties of the coating, as measured using a bending test. Three corrosion stages were observed, with equivalent circuits expressed by R(QR), R(Q(R(QR)))(QR) and R(Q(RW)). Highlights • A new method for treatment of coal fly ash was provided. • Coal fly ash improved the toughness of the potassium silicate coating. • Ni coated on the coal fly ash improved the conductivity between zinc particles. • Ni coated coal fly ash improved the anticorrosion properties of the coating. [ABSTRACT FROM AUTHOR]

Abstract Ideal electrodes should hold well-defined pore size distribution, high electrical conductivity and superior compatibility. Herein, we present a scalable strategy for the design and generation of macroporous frameworks based on N-doped hollow carbon spheres intercalated graphene film (GNC). In the unique structure, hollow carbon spheres separate the graphene nanosheets and provide convenience for ion entering the film and maximize the ion-accessible surface area. In situ deposition high performance MnO 2 on the surface of GNC film can help to enhance the specific capacity of the compounds. The obtained GNC/MnO 2 binder-free supercapacitor electrode exhibits ultrahigh volumetric capacitance 532.7 F cm−3 at 2 mV s−1. An asymmetric supercapacitor based on GNC/MnO 2 //GNC shows an ultrahigh volumetric energy density of 45.9 Wh L−1 at 1024 W L−1, which is much higher than the reported carbon based materials in aqueous electrolytes. The device also shows an excellent cycling stability with 93.1% initial capacitance after 5000 charge/discharge cycles. The device can light two LEDs, which indicates the potential of the composite for practical application. Graphical abstract Image 1 Highlights • N-doped hollow carbon spheres intercalated graphene film is rationally fabricated. • Macroporous frameworks can provide convenience for ion entering the film. • The GNC/MnO 2 //GNC supercapacitor shows an ultrahigh volumetric energy density of 45.9 Wh L−1. • The assembled asymmetric supercapacitor can successfully glow two parallel LEDs. [ABSTRACT FROM AUTHOR]

Abstract Vibratory finishing is an existing processing technology in the manufacturing process of aircraft engine blades. Laser shock peening (LSP) is to be applied in the blades manufacturing, and it is inevitable to combine with vibratory finishing. Firstly, the compound process sequence was determined by residual stress and surface roughness test on the Ti-3.5Mo-6.5Al-1.5Zr-0.25Si titanium alloy in this work, and the best-performing sequence of the compound process was ascertained to be LSP + vibratory finishing. Secondly, the surface microstructure was characterized after different surface treatments. It can be found that nanoscale grains were formed in the surface layer after LSP treatment, and more homogeneous nanostructure and lower surface roughness were achieved after LSP + vibratory finishing. Lastly, the vibration fatigue was chosen to verify the feasibility of the compound process. The results showed that the fatigue strength improved from 438 MPa to 544 MPa after the compound process treatment compared with the specimens treated by vibratory finishing only. Highlights • A compound process of LSP and vibratory finishing was proposed. • A surface nanostructure was produced in Ti alloy by the compound process treatment. • The fatigue strength was improved from 438 to 544 MPa after compound process treatment. [ABSTRACT FROM AUTHOR]

Abstract Effects of coverage layer on electrochemical corrosion behaviour and pitting morphologies of Mg-Al-Mn alloy subjected to massive laser shock peening (LSP) treatment were investigated by potentiodynamic polarisation test, electrochemical impedance spectroscopy (EIS), and scanning electron microscope (SEM) observations. Microstructures of Mg-Al-Mn alloy subjected to massive LSP treatment were also characterized. Results showed that LSP induced an obvious improvement in electrochemical corrosion resistance with increasing coverage layer. Even in a higher corrosive solution concentration, LSP could still prevent corrosion to some extent. The improvement in electrochemical corrosion resistance was due to the grain refinement and compressive residual stress induced by massive LSP treatment. Finally, the influence mechanism of the coverage layer on electrochemical corrosion behaviour of Mg-Al-Mn alloy was revealed. Graphical abstract Schematic illustration of the coverage layer on the electrochemical corrosion behaviour in NaCl solution. (a) The as-received, (b) the LSP-1, and (c) the LSP-4 specimen. Image 1 Highlights • LSP generated an obvious improvement in electrochemical corrosion resistance. • The increment of the coverage layer led to a stronger corrosion resistance. • Even in a more corrosive solution, LSP still prevent corrosion to a certain extent. • Influence mechanism of LSP coverage layer on corrosion resistance was revealed. [ABSTRACT FROM AUTHOR]

Abstract To obtain high efficient and lightweight microwave (MW) absorption material, a novel composite RGO/PANI/BaNd 0.2 Sm 0.2 Fe 11.6 O 19 (BNSF) was successfully synthesized. The RGO/PANI composite was synthesized by an in-situ polymerization, the BNSF was obtained via a chemical co-precipitation method and the RGO/PANI/BNSF ternary nanocomposite was fabricated through high energy ball mill. The phase composition, microstructure and MW absorption performance of samples were investigated and discussed. The results exhibited not only an excellent composite structure, but also an outstanding MW absorption performance. The RGO/PANI/BNSF nanocomposites exhibited excellent MW absorption property with 30 wt.% of BNSF, the minimum reflection loss (RL) could reach −50.5 dB at 13.68 GHz with the thickness of 2.90 mm. Meanwhile, the introduction of multiple polarization and relaxation in ternary composite were responsible for the enhancement of microwave attenuation and a broad effective absorption bandwidth (6.8 GHz). Based on the above results, we confirmed that the RGO/PANI/BNSF composite will have a considerable prospect in the electromagnetic interference shielding field. Highlights • A novel kind of ternary nanocomposites was prepared. • The microwave absorption mechanism of ternary nanocomposites was discussed. • The ternary nanocomposites possessed excellent microwave absorption properties. [ABSTRACT FROM AUTHOR]

Abstract A novel and one-pot calcination method is applied for the fabrication of SnS nanoparticles coated by ultrathin carbon layer on carbon paper, resulting in a SnS/C-carbon paper free-standing electrode for lithium ion batteries. In this hierarchical structure, the carbon layer has dual function of buffering the volume change of SnS and anchoring SnS nanoparticles on the substrate compactly. Besides, it also can boost charge transfer kinetic in the electrode. Meanwhile, the carbon paper with three-dimensional structure allows for fully absorption of electrolyte and provides efficient transport pathways for electrons. Benefiting from these structure features, the binder-free SnS/C-carbon paper electrode exhibits excellent cyclability and delivers a reversible capacity of 696.2 mAh g−1 at a current density of 0.5 A g−1 after 200 cycles. Besides, SnS/C-carbon paper free-standing electrode achieves a reversible capacity of 562.3 mAh g−1 at a current density of 2.0 A g−1, demonstrating a promising rate ability which is significant for high power applicants. Such one-pot and novel route to synthesize SnS/C-carbon paper free-standing electrode with excellent electrochemical performance can pave the way for the development of low-cost and time-saving fabrication of free-standing anode for high-performance lithium ion batteries. Graphical abstract Image 1 Highlights • The carbon-coated SnS nanoparticles are directly assembled on carbon paper. • The composite is prepared by novel and one-pot calcination method. • Carbon layer anchor SnS on the substrate compactly and buffer the volume change. • The carbon paper provides sufficient transport pathways for electron and Li ion. • The electrode shows extended cycle life and excellent rate performance. [ABSTRACT FROM AUTHOR]

Abstract Traditional powder/film-shaped photocatalysts suffer some serious limitations (such as recycling difficulty or high-cost) in the degradation of flowing wastewater. Herein, we report a novel filter-membrane-shaped photocatalyst by constructing MoS 2 /Bi 2 S 3 heterojunctions on carbon-fiber cloth (CF/MoS 2 /Bi 2 S 3 cloth). CF/MoS 2 /Bi 2 S 3 cloth consists of carbon-fibers (diameter: ∼15 μm) which are decorated with numerous MoS 2 nanosheets (thickness: ∼2 nm) and Bi 2 S 3 nanorods (length: 500–600 nm), and it exhibits a broad-spectrum photoabsorption from ultraviolet to near-infrared region (>1200 nm). Under visible-light irradiation, CF/MoS 2 /Bi 2 S 3 cloth (area: 4 × 4 cm2) exhibits the highest photocurrent (∼1.44 mA cm−2) and can photocatalytically remove 95.1% rhodamine B (RhB), 91.8% methylene blue (MB), 74.5% tetracycline (TC) and 75.5% hexavalent chromium (Cr(VI)) after 100 min, better than those by CF/MoS 2 cloth (37.0% RhB, 39.9% MB, 29.6% TC, 21.6% Cr(VI)) and CF/Bi 2 S 3 cloth (26.9% RhB, 27.4% MB, 20.9% TC, 25.9% Cr(VI)). Importantly, when flexible CF/MoS 2 /Bi 2 S 3 cloth (diameter: 10 cm) is used as the filter-membrane to degrade the flowing wastewater (rate: ∼1 L h−1), the removal efficiency of RhB increases from 19.7% at 1st to 94.6% at 8th filtering/degrading grade. Thus, CF/MoS 2 /Bi 2 S 3 cloth has excellent potential as a novel filter-membrane-shaped photocatalyst to degrade the flowing wastewater. Graphical abstract Image 1 Highlights • The growth of MoS 2 /Bi 2 S 3 on CF cloth have been realized. • CF/MoS 2 /Bi 2 S 3 cloth exhibits broad-spectrum photoabsorption and strong visible-light photocatalytic activity. • CF/MoS 2 /Bi 2 S 3 cloth was used as filter-membrane for degrading flowing wastewater. • The dominant active species are superoxide and the photogenerated holes. • CF/MoS 2 /Bi 2 S 3 cloth can be easily recycled and remains good stability. [ABSTRACT FROM AUTHOR]

Abstract New cathode LiVPO 4 F/C with high-performance was synthesized by using polyvinylidene fluoride (PVDF) as carbon source although there is no benzene ring in it. Compared with other carbon sources, the plateau, rate and cyclic performance of LiVPO 4 F/C are greatly enhanced when PVDF is used. The specific capacity of LiVPO 4 F/C containing 8 wt% carbon at 0.1 C, 1 C and 5 C are 148.1 mAh·g−1, 144.9 mAh·g−1 and 135.8 mAh·g−1, which is nearly the best reported results. Moreover, the TG-MS analysis is used to detect the gases released by different carbon sources in the sintering process. It shows that the Li 3 V 2 (PO 4) 3 /C impurity is greatly inhibited. This is because that HF gas released by PVDF can prevent the volatilization of fluorine and compensate the losses of fluorine. By contrast, the hydrogen free radicals released by other carbon sources can combine with fluorine and accelerate the volatilization of fluorine, resulting in the increasing of Li 3 V 2 (PO 4) 3 /C impurity. Then, the performance of LiVPO 4 F/C cathode containing more Li 3 V 2 (PO 4) 3 /C is greatly deteriorated. Graphical abstract Image 1 Highlights • High-performance LiVPO 4 F/C with few impurity Li 3 V 2 (PO 4) 3 /C is constructed by PVDF. • The capacity of LVPF-PV8 at 5C (135.8 mAh g−1) is nearly the best reported results. • HF released in the pyrolytic process of PVDF is proved by our designed experiment. • HF can prevent the volatilization of fluorine and compensate the loss of fluorine. • Li 3 V 2 (PO 4) 3 /C is formed and the capacity is deteriorated by other carbon sources. [ABSTRACT FROM AUTHOR]

Abstract A grain refinement process for a GH4169 superalloy sheet was proposed with the following parameters: solid solution (1050 °C × 0.5 h), cold rolling (50% reduction rate), δ phase precipitation treatment (890 °C × 10 h), high-pressure torsion (HPT) (3, 4, and 5 GPa), and recrystallization annealing (950 °C × 3 h). An ultrafine-grained sheet with an average grain size of 0.8 μm was prepared. The microstructure transformation, recrystallization process, and grain refinement mechanism of the materials in each stage were examined. Results revealed that large amounts of subgrain structures and irregularly shaped δ phases existed in the GH4169 superalloy exposed to HPT. During the recrystallization annealing at 950 °C, the dispersed and uniformly distributed δ phase blocked the migration of the recrystallized grain boundaries. The distorted microstructure after HPT was replaced with the newly formed fine grain without distortion, eventually forming an ultrafine grain structure with high-angle grain boundaries. After HPT processing was performed at 5 GPa × 2 turns, a cubic texture in the {100}<001> direction was produced in the GH4169 superalloy. Highlights • A new grain refinement process for a GH4169 superalloy sheet was proposed. • Ultrafine-grained sheet with an average grain size of 0.8 μm was prepared. • Grain refinement mechanism of the GH4169 superalloy sheet was analyzed by EBSD. [ABSTRACT FROM AUTHOR]

Abstract In this work, a highly concentrated Mg-18 wt%Gd binary alloy was prepared and its tensile creep behaviors were studied. Both as-solution (AS) and as-aged (AA) samples were subjected to creep tests at 523 K under various stresses. The results showed that precipitate variants and sizes became similar in AS and AA samples during their secondary creep stages. Strain aging and artificial aging play equivalent roles in the strengthening effects on AS and AA samples. Dislocation climb composed by edge < a > dislocations was the dominant creep mechanism of AS sample, and dislocations bypassing precipitates strengthened AS sample limitedly. By contrast, cross-slip composed by basal < a > and prismatic < a > dislocations was the dominant creep mechanism of AA sample, and dislocations cutting precipitates strengthened AA sample obviously. Furthermore, compared to AS sample, a high density of precipitate-free zones (PFZs) were developed in AA sample during creep testing. These high-density PFZs then relieved local stress concentration and catalyzed a homogeneous stress distribution, which postponed the occurrence of creep rupture rather than accelerated it. Accordingly, AA sample had an increased creep resistance than that of AS sample at 523 K. This unexpected discovery that PFZs could contribute to the increase in creep resistance is believed to extend the application of the Mg-Gd alloys with vast potentials. Graphical abstract Image 1 Highlights • As-solution (AS) and as-aged (AA) Mg-18Gd alloys are creep tested at 523 K. • Dislocation climb is the dominant creep mechanism of AS sample. • Cross-slip is the dominant creep mechanism of AA sample. • A higher density of precipitate-free zone (PFZ) is observed in AA sample. • High-density PFZs lead to an amazing enhancement of creep resistance of AA sample. [ABSTRACT FROM AUTHOR]

Abstract Novel porous CaO-Al 2 O 3 -SiO 2 -Si 3 N 4 glass-ceramics with in-situ grown rod-like β-Si 3 N 4 crystals were fabricated by sintering under a nitrogen atmosphere. Sintering behavior, microstructures and mechanical properties of various compositions in the CaO-Al 2 O 3 -SiO 2 -Si 3 N 4 system were investigated, using differential scanning calorimeter (DSC), X-ray diffractometry (XRD) and scanning electron microscopy (SEM) methods, followed by physical and chemical property measurements. Depending on our experiments, the coexistence of CaO-Al 2 O 3 -SiO 2 glass and α-Si 3 N 4 can lower the phase transition temperature of α-Si 3 N 4 and promote the in-situ formation and growth of β-Si 3 N 4 grains during sintering process. The in-situ grown rod-like β-Si 3 N 4 grains in the glass-ceramics are useful to the improvement of physical and chemical properties by addition of α-Si 3 N 4 to the system. This was attributed to that the in-situ grown β-Si 3 N 4 grains formed a spatial inter-locking microstructure. The physical and chemical properties of the porous glass-ceramics are mainly determined by the β-Si 3 N 4 content, the porosity and the residual glassy phase. The porous CaO-Al 2 O 3 -SiO 2 -Si 3 N 4 glass-ceramics with high porosity, high mechanical strength and low dielectric constant were obtained, indicating it is potential high-temperature industrial applications. Highlights • Porous CaO-Al 2 O 3 -SiO 2 -Si 3 N 4 glass-ceramics with excellent properties were obtained. • CaO-Al 2 O 3 -SiO 2 glass could effectively promote α-to β-Si 3 N 4 phase transformation. • Porosity and β-Si 3 N 4 content are the key factors that affect the properties. • Porous glass-ceramics show promise for high-temperature industrial applications. [ABSTRACT FROM AUTHOR]

Abstract The precipitate and solute distribution in a surface severely plastically deformed Al-Cu-Mg alloy were revealed by means of transmission electron microscopy and atom probe tomography. Accompanying gradient grain structure, there is a gradient precipitate architecture which evolves from undeformed needle-like S (Al 2 CuMg) precipitates to shear-deformed and fragmented S precipitates along low angle dislocation boundaries within coarse grains, to reprecipitated Gunier-Preston-Bagaryatsky (GPB) zones and S precipitates in lamellar nanograins, and to completely dissolved and segregated solutes to nanograin boundaries. Dislocation activities induced precipitate dissolution and promoted solute diffusion are two concomitant processes during precipitate and solute redistribution. The variation of precipitate crystallography, including orientation relationship deviation and coherency loss between S precipitates and Al matrix, was attributed to local changes in strain fields around undissolved S precipitates and in nucleation environment for reprecipitated S phase. Graphical abstract Image 1 Highlights • Precipitate and solute redistribution in a surface treated Al-Cu-Mg alloy was revealed. • SSPD induces precipitate dissolution and solute segregation to nanograin boundaries. • Dislocation activities promoted solute diffusion are benefit for GB segregation. • Precipitates keep deviated orientation relationship and incoherency with Al matrix. • The possible effect of plastic deformation on precipitate orientations was summarized. [ABSTRACT FROM AUTHOR]

Abstract Influence of a static 1 T magnetic field on the phase formation and solidified microstructure of Mg-24 wt%Nd alloy at the cooling rates of 6 °C/min and 14 °C/min is studied. Metastable Mg 12 Nd appears at 14 °C/min and 0 T, while the equilibrium phase Mg 41 Nd 5 is obtained at the same cooling rate and 1 T. The magnetic field induces the orientation of α-Mg dendrites and leads to the increase of compression strength of alloy (from 153 ± 3.6 to 167 ± 4.4 MPa). The contribution of magnetic field on Gibbs free energy is evaluated for the two phases. Combining with the CALPHAD method, transient nucleation theory and differential scanning calorimetry, the critical undercooling Δ T c for Mg 12 Nd and Mg 41 Nd 5 is analyzed to understand the promotion effect of magnetic field on equilibrium Mg 41 Nd 5. The Δ T c of Mg 12 Nd phase increases under 1 T magnetic field which is greater than that of Mg 41 Nd 5 (11 °C) at the cooling rate of 14 °C/min. Graphical abstract Image 1 Highlights • Phases of Mg-24 wt% Nd alloys change under a 1-T static magnetic field. • Critical undercooling is studied by CALPHAD method and transient nucleation theory. • Magnetic field promotes the equilibrium phase Mg 41 Nd 5 instead of Mg 12 Nd at large cooling rate. [ABSTRACT FROM AUTHOR]

Abstract By the simply mediated concentration of Na 2 SnO 3 and the solvothermal reaction time, a novel terminal hollowed Fe 2 O 3 @SnO 2 (TH-Fe 2 O 3 @SnO 2) heterojunction nanorods are synthesized by the inside-out ostwald ripening of SnO 2 nanoparticles. For comparison, olive-like Fe 2 O 3 nanorods covered with SnO 2 nanoparticles core-shell heterogeneous composites (Fe 2 O 3 @SnO 2) are also synthesized by a facile hydrothermal treatment method. The structure and morphology of the TH-Fe 2 O 3 @SnO 2 are investigated by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). It is found that the shells with 20–25 nm thickness of TH-Fe 2 O 3 @SnO 2 are composed of tetragonal SnO 2 particles (with an average diameter 10 nm), and the core of TH-Fe 2 O 3 @SnO 2 are formed of the corroded Fe 2 O 3 nanorods with 100 nm length and 50 nm widths. The formation mechanism of TH-Fe 2 O 3 @SnO 2 has also been studied on the basis of investigation of the concentration of Na 2 SnO 3 and the solvothermal reaction time. By comparison with single Fe 2 O 3 nanorods and Fe 2 O 3 @SnO 2 , the TH-Fe 2 O 3 @SnO 2 exhibits a higher reversible specific capacity of 570.7 mAh g−1 at the current density of 200 mA g−1 after 100 cycles. The unique terminal hollowed structure and synergetic effect of Fe 2 O 3 and SnO 2 can benefit to enhance the Li storage performance and are responsible for the enhanced electrochemical performances. Graphical abstract Image 1 Highlights • a novel terminal hollowed TH-Fe 2 O 3 @SnO 2 heterojunction nanorods are synthesized. • TH-Fe 2 O 3 @SnO 2 are used as high-performance Lithium ion battery anode materials. • TH-Fe 2 O 3 @SnO 2 exhibited the specific capacity of 570.7 mAh g−1after a 100 cycles. • Concentration of Na 2 SnO 3 and the solvothermal reaction time are also investigated. [ABSTRACT FROM AUTHOR]

Abstract Effects of massive laser shock peening (LSP) treatment as a function of coverage layer on surface residual stress, microstructure, and corrosion fatigue (CF) resistance of Fe-Cr alloy were studied by X-ray diffraction technique, scanning electron microscope observations, and corrosion fatigue crack growth (CFCG) testing. Special attention was paid to the details of compressive residual stress and fracture morphology, and the influence mechanism of coverage layer on CF behaviour was also determined. Results indicated that LSP generated deeper compressive residual stress and effectively decreased the CFCG rate, and increased coverage layers further improved the corrosion fatigue life of notched specimens. Highlights • Laser shock peening generated compressive residual stress in the surface layer. • Laser shock peening effectively decreased the corrosion fatigue crack growth rate. • Increased coverage layer further improved the corrosion fatigue life of Fe-Cr alloy. • Special attention was paid to compressive residual stress and fracture morphology. • Influence mechanism of laser shock wave on corrosion fatigue life was determined. [ABSTRACT FROM AUTHOR]

Abstract An equiatomic AlCrCuFeNi high entropy alloy (HEA) is fabricated successfully from the alloy powders using selective laser melting (SLM). Microstructural characteristics and mechanical behavior of SLMed AlCrCuFeNi samples under optimal SLM processing parameters are studied in detail. It is revealed that the SLMed AlCrCuFeNi HEA shows high crack sensitivity, and the optimum processing window is narrow. The formation of FCC phase is inhibited, resulting in a simple BCC solid solution to accommodate high lattice distortion and elastic strain induced by rapid cooling rate for the SLMed AlCrCuFeNi HEA. Moreover, unique fine columnar grains containing multiple ultrafine sub-grains structures appear within the molten pool and present a <100> preferred orientation. Nano-scale Cu-rich phases precipitate and exhibit chain-like at HAGBs while granular shape at LAGBs. Also, anomalous alternating bright and dark structures containing B2 and A2 phases with the width about 22 nm appear at the sub-grain boundaries due to rapid solidification. The SLMed AlCrCuFeNi HEA possesses superior properties with a compression strength of 2052.8 MPa and a fracture strain of 6.8% compared to the corresponding casting material. Fracture analysis indicates that the SLM (0°) specimen exhibits quasi-cleavage fracture while the SLM (90°) specimen shows intergranular fracture. The grain boundary strengthening effect, <100> preferential growth orientation of BCC grain and the existing microcracks are proposed to explain the anisotropy of compression properties. Highlights • A dual-phase high entropy alloy is fabricated using selective laser melting. • Unique columnar grains containing multiple ultrafine sub-grains are discovered. • Nano-scale Cu-rich phases exhibit chain-like at HAGBs while granular at LAGBs. • Anomalous spinodal structures containing B2 and A2 phases are discovered. • Anisotropy of compression properties exists in the SLMed AlCrCuFeNi alloy. [ABSTRACT FROM AUTHOR]

Abstract Effects of service temperature on the tensile properties and microstructural evolution of tensile specimens manufactured by commercial pure (CP) titanium subjected to laser shock peening (LSP) were investigated. Special attention was paid to the microstructural features at the top surface close to the fracture zone of the failed LSPed specimens at 20 °C, 150 °C, 250 °C, and 350 °C by means of transmission electron microscopy (TEM) observations. Results indicated that the ultimate tensile strength (UTS) of LSPed specimens gradually decreased, but the area reduction and elongation of LSPed specimens increased with the increment of service temperature. Furthermore, the influence mechanism of service temperature on the microstructural evolution of the LSPed CP titanium consisted of two modes: (a) ultra-high strain rate inhibited the dislocation motion at a lower temperature which was more prone to the occurrence of deformation twinning, and (b) ultra-high strain rate was easier to activate dislocation motion at a higher temperature, making deformation twinning disappear in the plastic deformation layer of CP titanium. Graphical abstract Image 1 Highlights • Increasing temperature is easier to generate necking phenomenon of LSPed CP titanium. • Ultimate tensile strength of LSPed specimens decreased with increasing temperature. • Microstructural features of failed specimens at various temperatures were presented. • Influence mechanism of temperature on microstructure of LSPed specimen was revealed. [ABSTRACT FROM AUTHOR]

Abstract A study on 0.8BaTi 4 O 9 -0.2BaZn 2 Ti 4 O 11 (BZT) filled and glassfiber (GF) reinforced polytetrafluoroethylene (PTFE) was described. The content of GF was 4 wt. %, and the BZT content varied from 26 wt. % to 66 wt. %. BZT complex phase powder was prepared by one synthetic route and modified using perfluorooctyltriethoxysilane (F8261). The microstructure, thermal properties, dielectric properties and temperature coefficient of dielectric constant of the composites were investigated in detail. The results revealed that BZT/GF/PTFE composites hold outstanding dielectric properties and stable thermal properties. Moreover, the specimens exhibited strong hydrophobicity due to the modification of filler using F8261. The BZT/GF filled PTFE composites exhibited reliable dielectric constant (ε r = 4.4), acceptable dielectric loss (tan δ = 0.001), low water absorption (0.02%) and a near-zero temperature coefficient of dielectric constant (τ ε = 1.57 ppm/°C) at filler with contents of 4 wt. % GF and 46 wt. % BZT. Highlights • 0.8BaTi 4 O 9 -0.2BaZn 2 Ti 4 O 11 ceramics were prepared by one synthetic process. • The surface of BZT was successfully modified by C 14 H 19 F 13 O 3 Si. • Modified BZT is hydrophobic resulting in low water absorption in composite. • Increasing BZT contents will increase the density and ε r of the composites. [ABSTRACT FROM AUTHOR]

Abstract A co-precipitation combined with hydrothermal method is adopted for synthesizing Li 0.9 Na 0.1 Mn 1-x Ni x PO 4 /C (x = 0, 0.05, 0.1, 0.15, 0.2, 0.3) nanocomposites, using high specific surface area Li 2.7 Na 0.3 PO 4 precursor, MnSO 4 ·H 2 O, Ni(NO 3) 2 ·6H 2 O as raw materials. The X-ray diffraction analysis results shows doping ions have not destroy the crystal structure of olivine LiMnPO 4 /C composites. It can be also seen from the scanning electron microscope that the primary particles connect with each other on the surface at the nanometer scale. In all doping ratios, the obtained Li 0.9 Na 0.1 Mn 0.9 Ni 0.1 PO 4 /C composite shows excellent rate capability with the discharge capacity of 157.9 mAh/g and 150.5 mAh/g at 0.05 C and 1 C, respectively. With the increasing of cycle numbers, the capacity fades slightly. In conclusion, dual ion doping can significantly improve the lithium ion diffusion rate by broaden the transport channel. Highlights • Hollow structure Li 2.7 Na 0.3 PO 4 precursor with high specific surface area is prepared. • A simple hydrothermal method to synthesize co-doped Li 0.9 Na 0.1 Mn 0.9 Ni 0.1 PO 4 /C composite is present. • The initial discharge capacity of Li 0.9 Na 0.1 Mn 0.9 Ni 0.1 PO 4 /C is 157.9 mAh/g and 150.5 mAh/g at 0.05 C and 1 C, respectively. • Li 0.9 Na 0.1 Mn 0.9 Ni 0.1 PO 4 /C shows good rate performance. [ABSTRACT FROM AUTHOR]

Abstract The magnesium matrix nanocomposites (10 vol% and 15 vol% of SiC particles) with a hierarchical structure, which contained flake-like soft phases, were investigated by compression and modeling. Fortunately, the unique malleability of hierarchical Mg nanocomposites was observed. The fracture surfaces indicated that the hierarchical Mg nanocomposites demonstrated ductile rupture. The "pull-out" phenomenon on the fracture surfaces suggested that the flake-like soft phase could sustain the additional deformation, consequently improving the malleability of Mg nanocomposites. Additionally, the modeling demonstrated that the effects from soft phase were not negligible, where the modified model exhibited a better agreement on the yield strength of the hierarchical Mg nanocomposites. Highlights • The unique malleability of hierarchical Mg nanocomposites was recorded with ductile rupture. • The "pull-out" of the flake-like soft phase in the hierarchical nanocomposite was observed. • A modified strengthening model was proposed to predict the yield strength. [ABSTRACT FROM AUTHOR]

Abstract In this work, the microalloying approach was adopted to improve the mechanical properties of Mg-6Zn-0.5Zr alloy by co-addition of trace Cu and Ce elements. The results showed that the grain size of the Mg-6Zn-0.5Zr-0.5Cu-0.5Ce alloy was refined, and MgZnCu and Mg-Zn-Ce phases formed by the microalloying of Cu and Ce. In addition, high-density nano-scale precipitates were found in the matrix after extrusion. The alloy with Cu and Ce addition showed a basal texture with a stronger texture intensity. The yield strength, ultimate tensile strength and elongation of the as-extruded Mg-6Zn-0.5Zr-0.5Cu-0.5Ce alloy were 304 MPa, 345 MPa and 20.0%, respectively. This work demonstrated a close microstructure-strength relationship in which the refined grain size and abundant nano-scale precipitates led to an increase in the tensile yield strength of approximately 59 MPa compared with that of the Cu and Ce free alloy. Highlights • Abundant nano-scale precipitates formed in ZK60-0.5Cu-0.5Ce alloy during extrusion. • The Mg-Zn-Ce phase with an orthorhombic structure was confirmed in this study. • The as-ext ZK60-0.5Cu-0.5Ce alloy showed a strong basal texture. • The tensile yield strength increased of 59 MPa after the co-addition of Cu and Ce. [ABSTRACT FROM AUTHOR]

Abstract Tungsten is one of the most promising candidates for plasma-facing material for fusion. In this experiment, W–TiC–Y 2 O 3 composites were successfully prepared by the wet chemical method. The properties of the W–TiC–Y 2 O 3 composites were studied through field-emission scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction analysis, thermal conductivity, and transient laser thermal shock. During the sintering of the composite powder, TiC and Y 2 O 3 precipitations converted to Y-Ti-O precipitations. After transient laser thermal shock, the composites underwent melting, cracking, and resolidification, resulting in changes in surface morphology and internal structure of the composites. Graphical abstract Image 1 Highlights • W–TiC–Y 2 O 3 composites possessed excellent mechanical property and thermal shock resistance. • Y 2 TiO 5 , Y 2 TiO 6 , and Y 2 TiO 7 improved the mechanical properties of the material at high temperature. • The effect of different power density on material surface was analyzed. • The change of surface morphologies and internal structure due to transient thermal shock were discussed. [ABSTRACT FROM AUTHOR]

In this work, it is successfully achieved to synthesize the three-dimensional flowerlike Ni (1-x) Mn x Fe 2 O 4 (x = 0, 0.02, 0.04, 0.06, 0.08, 0.1) by an environmental hydrothermal method. The morphology and structure of as-prepared Ni (1-x) Mn x Fe 2 O 4 are characterized via X-ray diffraction, scanning electronic microscopy and nitrogen adsorption-desorption isotherms, besides, the magnetic properties of the samples is revealed by vibrating sample magnetometer. The results show that the Ni (1-x) Mn x Fe 2 O 4 are cubic spinel phase with three-dimensional flowerlike microspheres structure assembled by nanosheets, which is exhibited the good performance to remove Congo red (CR). Besides, the samples with good magnetic properties facilitates magnetic separation for CR solution. The kinetics and isotherm of adsorption process are studied via a UV–visible spectrophotometer. The adsorption process is found to fit the pseudo-second-order kinetic model and Freundlich isotherm model better. Moreover, the adsorption capability of CR on Ni (1-x) Mn x Fe 2 O 4 has a great enhancement by the appropriate doping of Mn 2+ ions. In order to research the mechanism of the CR adsorption process, the effect of pH value and the surface group of the samples and CR are measured. Due to the doping of Mn 2+ ions, the surface activity of Ni (1-x) Mn x Fe 2 O 4 has been changed and the adsorption capability (231.74546 mg g −1 ) of CR on Ni 0.98 Mn 0.02 Fe 2 O 4 is maximum in the all samples at pH 5. This research suggests that appropriate doping of Mn 2+ ions could enhance the adsorption performance for CR, which provides a new idea for the development of adsorbent. [ABSTRACT FROM AUTHOR]