Search

Chemical short-range order (CSRO) is a typical microstructural characteristic commonly found in multi-principal element alloys (MPEAs). For MPEAs with the face-centered cubic (FCC) structure, the presence of CSRO has been verified and characterized meticulously by using electron microscope. However, it is still challenging to reveal the effect of CSRO structure on the deformation microstructure and micromechanical behavior of those alloys. By applying atomic scale simulations, this study explores the micromechanical behavior of an equiatomic CoCrNi medium entropy alloy with random solid solution and three different degrees of CSRO under plane strain compression, respectively. The results show that CSRO can effectively promote planar slip of dislocations in the FCC matrix and elevate flow stress of the alloy. The planar slip and stacking of partial dislocations then lead to the formation of hexagonal-close-packed (HCP) structure lamellae. CSRO also modulates the morphology of dislocations. When dislocations cut through CSRO, it hinders the movement of dislocations while being destroyed by atomic plastic flow, causing CSRO and atomic clusters at the interface of the matrix to embed each other and generate antiphase boundaries which can significantly enhance the bulk yield strength. These findings provide fundamental insights into the interaction between CSRO and dislocations in CoCrNi MEA, guiding the design of MPEAs with superior combinations of strength and ductility. [Display omitted] • Interaction between chemical short-range order (CSRO) and dislocations in the CoCrNi MEA is unraveled. • Deformation mechanisms depend on the degree of CSRO. • Plastic deformation deteriorates CSRO. The more significant the CSRO, the easier it is to be destroyed with deformation. [ABSTRACT FROM AUTHOR]

The development of high-performance room temperature gas sensors remains a great challenge. Herein, a novel three-dimensional (3D) Fe 2 O 3 nanoflowers (NFs)/Ti 3 C 2 T x derived TiO 2 nanosheets (NSs) hierarchical heterostructure was prepared by hydrothermal treatment and chemical bath deposition (CBD) method. With the unique structure, two-dimensional (2D) Ti 3 C 2 T x derived TiO 2 NSs provide an ideal platform for the nucleation and growth of the Fe 2 O 3 NFs. By controlling the CBD time, the growth evolution of Fe 2 O 3 NFs onto Ti 3 C 2 T x derived TiO 2 NSs can be effectively regulated. At room temperature, the Fe 2 O 3 /Ti 3 C 2 T x derived TiO 2 sensor with optimal CBD time (45 min) exhibits the highest sensitivity of 48.6% for 10 ppm H 2 S, while both the Fe 2 O 3 and Ti 3 C 2 T x derived TiO 2 sensors have nearly no response to 50 ppm H 2 S. Additionally, the Fe 2 O 3 /Ti 3 C 2 T x derived TiO 2 sensor displays the high selectivity to H 2 S, low limit of detection (200 ppb) and good repeatability. The constructing of 3D Fe 2 O 3 /Ti 3 C 2 T x derived TiO 2 hierarchical heterostructure opens a new route to develop other high-performance room temperature gas-sensing materials. [Display omitted] • Fe 2 O 3 /Ti 3 C 2 T x derived TiO 2 heterostructure was prepared by hydrothermal treatment and chemical bath deposition. • Ti 3 C 2 T x derived TiO 2 nanosheets provide an ideal platform for the nucleation and growth of the Fe 2 O 3 nanoflowers. • The gas sensor achieved low-concentration detection of H 2 S at room temperature. [ABSTRACT FROM AUTHOR]

Bulk metallic glass composites (BMGCs) containing an in-situ formed metastable β phase (β-type BMGCs) being capable of transforming to martensites, are a promising class of alloys. Nonetheless, the influence of the structural metastability of β phases on the deformation mechanisms of BMGCs remains largely unclear. This, however, is crucial for understanding and optimizing plastic deformability. In this study, three Ti-based β-type BMGCs with nominal compositions of (Ti 0.505 Zr 0.353 Fe 0.028 Be 0.114 ) 100− x Cu x ( x = 1, 5, 8) have been developed, in each of which the β-Ti phase has a different metastability. For x = 8, the β phase precipitates exclusively and does not transform martensitically during deformation. At the lowest Cu content ( x = 1), however, the β phase contains a high density of fine ω phase upon quenching, which hinders the deformation-induced martensitic transformation. β phases in both BMGCs deform plastically by dislocation glide. Only when x = 5 does the β phase undergo the martensitic transformation to α″-Ti due to an appropriate degree of metastability. The reversible phase transformation between β and α″ followed by twinning in α″ on continuing deformation leads to a “double yielding” behavior and results in strong work-hardening capability as well as superelasticity during compression (cyclic loading) tests. [ABSTRACT FROM AUTHOR]

Abstract: The wetting behavior and interfaces of CuZr-based glassy alloys/W system were investigated by the sessile drop method. It was found that Cu50Zr50/W, Cu47.5Zr47.5Al5/W and Cu40Zr44Al8Ag8/W system had the final equilibrium contact angle around 18°, 8° and 3° at corresponding experimental temperatures. Base on the scanning electron microscopy observing, no reaction product can be found at the interface of Cu47.5Zr47.5Al5/W and Cu40Zr44Al8Ag8/W, and some granular reaction products appeared along the interface of Cu50Zr50/W. The present work indicates that Cu47.5Zr47.5Al5 and Cu40Zr44Al8Ag8 bulk metallic glasses (BMGs) are appropriate for the fabrication of W reinforced BMGs matrix composite. [Copyright &y& Elsevier]

Abstract: This paper presents a class of Zr-based bulk glassy alloy with enhanced plasticity. The microstructure of this glassy alloy consists of dispersion of 2–5nm nanocrystallites embedded in the glassy matrix. Under compression, this glassy alloy displays high strength up to 2250MPa together with a large plastic strain of 5.5–14.5%. The improved plasticity is ascribed to the interaction between shear bands and nanocrystallites. [Copyright &y& Elsevier]

In this paper, heterogeneous L1 2 particles were successfully introduced into Ni 38 Co 25 Fe 13 Cr 10 Al 7 Ti 7 MPEA by two-stage aging treatment. Compared with the homogeneous particles, the heterogeneous L1 2 particles strengthened alloy exhibits enhanced strength-plasticity synergy. The tensile elongation is 23.2%, which is higher than all samples with the homogeneous particles, and the yield strength remains at 942 MPa, which is equivalent to the micro particles (972 MPa) with the highest yield strength in the homogeneous particles. Further analysis of the strengthening and deformation mechanisms revealed that precipitation hardening, and heterogeneous deformation-induced hardening were the main factors for the enhanced strength. The deformation-induced layered fracture networks, high-density Lomo-Cottrell locks, and heterogeneous L1 2 particles microstructure characteristics significantly improve the strain hardening ability; GNDs accumulate at the heterogeneous interface to alleviate the stress concentration at the GBs and improve the tensile plasticity of the MPEA with heterogeneous L1 2 particle structure. The heterogeneous L1 2 particle structure obtained through two-stage aging treatment without severe mechanical deformation has attractive engineering application potential. These properties of Ni 38 Co 25 Fe 13 Cr 10 Al 7 Ti 7 MPEA with heterogeneous L1 2 particle structure have important enlightening and practical value. • Designed and prepared Ni 38 Co 25 Fe 13 Cr 10 Al 7 Ti 7 MPEA with heterogeneous L1 2 particles. • Heterogeneous L1 2 particle structure obtained through simple two-stage heat treatment process. • The heterogeneous L1 2 particle reinforced alloy exhibits superior mechanical properties. [ABSTRACT FROM AUTHOR]

• A facile method for fabrication of AuAg alloy nanoplates with controlled elemental compositions was developed. • They were characterized with a unique morphology of wavy nanoplate, together with sub-15 nm in thickness. • Tunable LSPR properties and satisfying photothermal performance were demonstrated. Gold-silver alloy wavy nanoplates with tunable elemental compositions are successfully prepared, exhibiting strong NIR absorbance and excellent photothermal properties. [Display omitted] We report a facile synthesis of AuAg alloy nanoplates in high purity, together with tunable elemental compositions and uniformity in size and morphology. The success of current work relies on the one-pot co-reduction of Au and Ag precursor in an ice-water bath with the presence of octadecyltrimethylammonium chloride (OTAC) as a capping agent. With the increase in Ag content, the localized surface plasmon resonance (LSPR) of AuAg alloy nanoplates exhibited a noticeable blue-shift from near-infrared (NIR) to visible region. Thanks to the well-defined NIR LSPR properties and broad spectral range, the current products exhibit a remarkably integrated high-quality photothermal feature as well as the efficient photothermal conversion. Meanwhile, the current AuAg alloy nanoplates demonstrate satisfying photothermal stability verified via continuous exposure and cyclic irradiation by an 808-nm laser. The present study offers a facile route to the preparation of two-dimensional AuAg alloy nanocrystals with tunable elemental compositions and validates their excellent responses towards photothermal measurements, which could find promising use in photothermy-based diagnosis and therapy. [ABSTRACT FROM AUTHOR]

• HybridNiO@Co 3 O 4 NTAs were fabricated via two-stepdeposition and etching method. • NiO@Co 3 O 4 NTAselectrode has a specific capacitance of 1769.2 F/g and 87.5% capacitance retention. • Unique composites structure of hierarchically hollow NiO tubes and wrapped Co 3 O 4 nanosheets. • Synergistic effects lead to the improved capacitance behavior. • DFT calculations reveal band-gap disappearance for the mechanism of conductivity improvement. [Display omitted] Novel band-gap shrinked NiO@Co 3 O 4 nanotube arrays on Ni foam have been fabricated via a two-step synthesis route. Hexagonal NiO nanotube arrays are obtained by electrodeposition of Ni nanoparticles onto ZnO nanoprisms followed by selective dissolution of ZnO. The inside and outside surfaces of the NiO nanotubes are homogeneously covered with Co 3 O 4 nanosheets via hydrothermal treatment, which enlarges the surface area and accelerates electron transferring. Benefiting from the hierarchically hollow structure and the synergistic effects, the obtained NiO@Co 3 O 4 nanotube arrays deliver a superior specific capacitance of 1769.2 F/g at 1 A/g and outstanding cycling stability (87.5% capacitance retention after 10,000 cycles at 20 A/g). Density functional theory calculations reveal that the disappearance of the band-gap of the NiO@Co 3 O 4 composite is one intrinsic reason that the conductivity and the capacitive charge storage performance are enhanced significantly. The as-prepared NiO@Co 3 O 4 nanotube arrays are highly promising electrodes for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

The wetting characteristics of Ti 32.8 Zr 30.2 Fe x Cu 14.3- x Be 22.7 (at.%, x = 0, 2.5, 5.3) bulk metallic glasses (BMGs) with W substrate are conducted using the sessile drop method at different temperatures. The effect of Fe content on wettability is systematically studied. At a given temperature, contact angle initially rises and subsequently declines as the Fe content increases from 0 at.% to 5.3 at.%. Optimal wettability is observed in BMGs devoid of the Fe element. This is attributed to the influence of Fe addition on the elemental diffusion behaviors and two-phase interfacial morphologies during wetting. The addition of 2.5 at.% Fe leads to a significant accumulation of Ti element at the wetting interface and prevents the wetting process. As the Fe content increases to 5.3 at.%, the conspicuous abundance of Fe in the glass phase together with the diffused Cu in W substrate determines the wettability of the system. These findings not only reveal the influence of Fe content on the wetting properties of the TiZr-based BMGs/W system but also provide a theoretical basis for the preparation of ex-situ BMG composites. • The contact angle first increases and then decreases with increasing Fe content. • Optimal wettability is observed in BMGs devoid of the Fe element. • Fe content has a significantly influence on the interface morphology of wetting. • Diffusion behavior of atomic clusters directly determines interfacial wettability. [ABSTRACT FROM AUTHOR]

Abstract: The effects of high magnetic fields on the as-cast microstructure and grain boundaries of binary Al–Li alloy were investigated. It was found that secondary dendrite arm spacing (SDAS) decreased and the distribution of the SDAS became uniform under high magnetic fields. The application of a high magnetic field had no effect on the type of precipitated phases in the alloy, although δ′ (Al3Li) precipitates coarsened under the field of 11.5T. Area fraction of grain boundary (AFGB) slightly decreased at first and then increased with increasing magnetic flux density under uniform magnetic fields, while it decreased under magnetic field gradients. [Copyright &y& Elsevier]

Martensitic amorphization is a novel phenomenon of solid-state amorphization firstly reported in metastable β-Ti alloys. However, the mechanical properties of the β-Ti alloys containing intragranular amorphous martensite remain unexplored. In this work, the microstructures, compressive and tensile properties of the (Ti 0.615 Zr 0.385) 100–3.9 x (Cu 2.3 Fe 1.6) x alloys were investigated. It is found that martensitic amorphization exists in the as-cast Ti 59.1 Zr 37 Cu 2.3 Fe 1.6 (x = 1) alloy. During compression, deformation-induced β-Ti to α″-Ti martensitic transformation takes place in the alloy with x = 1. With increasing x , the deformation-induced martensitic transformation of β→α″ is fully suppressed due to the increased phase stability. The Ti 59.1 Zr 37 Cu 2.3 Fe 1.6 alloy with amorphous martensite exhibits the highest yield strength during compression, which is attributed to the strong blocking effect of the dislocation glide by the intragranular amorphous phase. However, the Ti 59.1 Zr 37 Cu 2.3 Fe 1.6 alloy exhibits catastrophic failure without plasticity upon tension, which is associated with the brittle nature of the amorphous phase under tension as well as the severe stress concentration between the crystalline and amorphous phases. These results correlate the microstructures and mechanical properties of the Ti-based alloys with martensitic amorphization. • The contents of Cu and Fe determine the microstructure of CF x alloys. • Successfully prepared CF1 alloy containing amorphous martensite. • Amorphous martensite has strengthening effect in compression tests. • CF1 alloys have no tensile plasticity. [ABSTRACT FROM AUTHOR]

Abstract Alloy powders with dual-phase nanocrystal (NC) and nanoglass (NG) have received much attention due to its small coercive force and high permeability, but the preparation of dual-phase high entropy alloy powders (HEAPs) simultaneously with larger aspect ratio constitute a great difficulty in microwave absorbing domain. Here, a new concept has been devised to tune the crystallinity of microwave absorber by regulating the phase proportion of milling precursor. A combination technology containing melting, strip casting, and milling has been adopted to prepare a serious of FeCoNiSi x Al 0.4 HEAPs to verify its correctness. Selective phase transition occurs in dry-milling process, generating various unique microstructures - NCs, NGs, and NGs embedding in NC grain. Besides, BCC phase content of HEAPs can be controlled by the amount of added ethanol. A less coercive force, increasing from 14.05 Oe (C 0.1) to 23.43 Oe (C 0.5), and a large magnetic permeability, varying from 2.41 (C 0.5) to 2.80 (C 0.3) at 1 GHz, can be obtained. Highlights • The crystallinity of powders relate to FCC phase proportion of milling precursor. • The phase structure of nanocrystal alloy ribbons can be tuned by element content. • Co-existed phase transitions promote the formation of dual-phase microstructure. • The variety of crystallinity lead to the change of magnetic properties. [ABSTRACT FROM AUTHOR]

Ultra-broadband electromagnetic absorption has become a critical issue competing with the advanced broad-band electromagnetic detection systems. In this study, a novel metamaterial with periodic square frustums was designed and prepared, based on the carbonyl iron powder/carbon fiber/Resin composites. The electromagnetic parameters for each component of the meta-structure were determined by the addition content of carbonyl iron powder and carbon fiber, and the prepared metamaterial with optimized electromagnetic and structural parameters realized efficient EM absorption (>90%) in the frequency band of 3.5–40 GHz. Additionally, the electromagnetic absorption mechanism is believed to be attributed to the synergic result of the multiple electromagnetic loss modes and the improved impedance matching caused by the multi-scale structure. Therefore, the proposed metamaterial absorber realizes an ultra-broadband electromagnetic absorption with a coordinated optimization of electromagnetic parameters and meta-structure, which could be served as electromagnetic wave absorbing devices for broadband absorption applications. • A novel metamaterial with periodic square frustums was designed and prepared. • Efficient EM absorption (>90%) in frequency band of 3.5–40 GHz was realized. • The design strategy for this ultra-broadband metamaterial was verified. • The electromagnetic wave absorption mechanism was specified. [ABSTRACT FROM AUTHOR]

The effect of Ti content on the microstructure and mechanical properties regulation for Fe 45 Ni 30−x Cr 15 Al 10 Ti x high entropy alloys (HEAs) with a duplex FCC/BCC structure is investigated. The as-cast Fe 45 Ni 30−x Cr 15 Al 10 Ti x HEAs have typical dendrite and inter-dendrite structure, where dendric and inter-dendric regions are FCC and BCC phases, respectively. After introducing Ti, the inter-dendric structure transforms into coexistence of disordered BCC and ordered B2/L2 1 phases. And the morphology of B2/L2 1 precipitates gradually changes from a regular maze-like mesh and cuboidal structure to elliptical structures due to the increase of the lattice mismatch. The change of precipitate type and volume fraction lead to that the ultimate tensile strength of the HEAs increases from 540 MPa to 1292 MPa. Meanwhile, it keeps the uniform elongation of 13.29%, showing outstanding strength-plasticity synergy. • A multi-phase coexistence HEA with superior mechanical property was designed. • The addition of Ti led to precipitation of hierarchical B2/L2 1 phase from BCC phase. • As the Ti content increased, the morphology of precipitates changed. [ABSTRACT FROM AUTHOR]

TiAl-based alloy is an excellent high-temperature structural material, but poor hot workability has been the bottleneck hindering its development. In this study, we take into account the hot workability and mechanical properties of Ti-48Al alloy through microstructure adjustment. Powder metallurgy Ti-48Al alloy prepared by vacuum sintering is used as the raw material, which has a near-γ microstructure composed of equiaxed grains. Although the composition is simple, the alloy achieves high mechanical properties after forging with 75 % deformation. Controlling the forging temperature to 1300 °C can make the microstructure transform into a duplex structure composed of γ/α2 lamellar colonies and γ equiaxed grains. As-forged alloy has an ultimate tensile strength of 650 ± 17 MPa and a yield strength of 644 ± 16 MPa at room temperature. It still maintains high strength at high temperature, with ultimate tensile strength of 684 ± 19 MPa at 500 °C, 700 ± 19 MPa at 700 °C, and 320 ± 10 MPa at 900 °C. In addition, the alloy has good ductility with elongation of 58.2% due to dynamic recrystallization at 900 °C. • Mechanical property is significantly improved by forging with simple composition. • The alloy has ultrafine equiaxed grain of 2.45 µm and lamellar spacing of 20–50 nm. • Duplex microstructure without remnant lamellae forms in PM Ti-48Al alloy. • Ti-48Al alloy exhibits great plasticity of 58.2 % at 900 °C. [ABSTRACT FROM AUTHOR]

Bulk metallic glass composites containing in-situ formed β-Ti/Zr phases (β-type BMGCs), which exhibit a good combination of strength and plasticity, were generally developed by adding β-stabilizers, such as Nb, Ta, V, etc., into Ti/Zr-based bulk metallic glasses (BMGs). In this work, an iteration method is proposed to develop β-type BMGCs from Ti/Zr-based BMGs, and the compositions of BMGCs can be designed by “the composition of in-situ formed β phase (the iterative variable) + the composition of BMG”. Due to the fast elemental diffusions between the β phase and the (supercooled) liquid phase, the iteration method can develop β-type BMGCs in which both phases can maintain a mutual (metastable) equilibrium during solidification. The procedures of the iteration method and its underlying thermodynamic and kinetic principles are discussed, and a Zr 56.9 Ti 18.8 Cu 7.4 Ni 5.7 Be 11.3 BMGC was developed from Vitreloy 1 by using the iterative method. As compared with β-type BMGCs developed by the conventional method, β-type BMGCs developed by the iteration method have two advantages: (i) the good glass-forming ability of the initial BMGs can be largely inherited by the glassy matrices in BMGCs; (ii) without adding β-stabilizers, the in-situ formed β phases are more likely to be metastable. The current iteration method is of scientific significance on improving plasticity of Ti/Zr-based BMGs and developing new β-type BMGCs. [ABSTRACT FROM AUTHOR]

The multi-principal element alloys (MPEAs), which are also called high-entropy alloys (HEAs) or medium-entropy alloys (MEAs) based on the multi-principal element number, received intensive attention due to their unusual phase structures and potential application in diverse aspects. However, quantitative and graphical characterization of the atom distribution, lattice distortion, and mechanical properties are considerably insufficient, which hinders the exploration and development of the rich ore of MPEAs. In this work, a general and comprehensive approach was proposed to simulate the atom distribution, lattice distortion, and mechanical properties of MPEAs based on site preference, where FCC_CoNiV and CoCrNi MPEAs were demonstrated and compared quantitatively and graphically. For this purpose, the temperature- and composition-dependent site occupying fractions (SOFs) of MPEAs were predicted using a two-sublattice model based on the crystallographic information of the prototype of MPEAs, where the corresponding thermodynamic database concerning the temperature-dependent Gibbs free energy of formation of the involved end-member compounds was established in this work using first-principles calculations based on density-functional theory (DFT) and density-functional perturbation theory (DFPT). For FCC_CoNiV MPEA，the site occupying configuration is (V 1.0000) 1a (Co 0.4444 Ni 0.4445 V 0.1111) 3c , which is not affected by the heat treatment temperature, while for FCC_CoCrNi MPEA, the site preferences change continuously and slightly with the increase of the heat treatment temperature, for example, the site occupying configuration changes from (Co 0.3371 Cr 0.0002 Ni 0.6627) 1a (Co 0.3320 Cr 0.4444 Ni 0.2236) 3c at 673 K to (Co 0.3690 Cr 0.0007 Ni 0.6303) 1a (Co 0.3214 Cr 0.4442 Ni 0.2344) 3c at 1273 K. From the long-range ordered structures, the locally ordered structures were explored further by statistically analyzing the coordination number of the atom coordinated with the same type of atoms in a 30×30×30 FCC supercell based on the prototype of L1 2 _AuCu 3 which contains 108,000 atoms. It was found that all the maximum numbers n for Co*‐nCo, Ni*‐nNi, and V*‐nV are only 8 in FCC_CoNiV MPEA, respectively, while the maximum numbers n for Co*‐nCo, Cr*‐nCr, and Ni*‐nNi are 10, 8, and 10 in FCC_CoCrNi MPEA, respectively. Thus, all coordination numbers in the studied MPEAs are less than 12, i.e., the coordination number of the pure metal with a FCC unit cell. The calculated relative lattice distortion of FCC_CoNiV MPEA is 2.54%, which is larger than that of FCC_CoCrNi MPEA (2.25%) by comparing the corresponding structure with and without distortion based on the predicted site configuration at 973 K. Besides the difference in the total energy, the resultant force acting on each atom of the FCC_CoNiV MPEA with and without distortion was graphically characterized to explore the mechanism of lattice distortion. For the mechanical properties, both alloys show ductile, while the elastic anisotropic of FCC_CoNiV MPEA is larger than that of FCC_CoCrNi MPEA, the strong ordering behaviors of V atoms may contribute to these behaviors. Current results agree well with the limited experimental and simulated reports concerning the ordering behavior of V atom and ductile characters. Thus, a general approach was established, which can be applied to simulate the atom distribution, lattice distortion, and mechanical properties of MPEAs based on site preference. We expect that the current approach may act as a standard simulating strategy on MPEAs beyond the traditional random mixing consideration of the different constituent atoms. [Display omitted] • A general simulating approach was proposed on multi-principal element alloys (MPEAs) based on site preference. • The approach characterizes the atom distribution, lattice distortion, and mechanical properties. • The FCC_CoNiV and CoCrNi MPEAs were demonstrated and compared quantitatively and graphically in detail. • The atom distribution, lattice distortion, and mechanical properties of FCC_CoNiV and CoCrNi MPEAs are rather different. [ABSTRACT FROM AUTHOR]

Addition of a small amount of La and Co enhances the stabilization of supercooled liquid and glass-forming ability (GFA) of an Al 85 Ni 7 Er 8 metallic glass. The Al 85 Ni 5 Co 2 Er 6 La 2 alloy exhibits large supercooled liquid region of 40 K, high GFA with a critical thickness of 450 μm, and the viscosities on the order of 10 7 −10 9 Pa s in the supercooled liquid state. The Al-based glassy nano-scale patterns were formed by imprinting, indicating its good thermoplastic formability. The possible mechanism for the improvement of the supercooled liquid stability of the Al Ni Er alloy by addition of La and Co elements was discussed in terms of the crystallization behavior. [ABSTRACT FROM AUTHOR]

The stress-induced phase transformation and micromechanical behavior of CuZr-based alloy were investigated by in-situ neutron diffraction. The pseudoelastic behavior with a pronounced strain-hardening effect is observed. The retained martensite nuclei and the residual stress obtained from the 1st cycle reduce the stress threshold for the martensitic transformation. A critical stress level is required for the reverse martensitic transformation from martensite to B2 phase. An increase of intensity for the B2 (110) plane in the 1st cycle is caused by the twinning along the {112}<111> twinning system. The convoluted stress partitioning influenced by the elastic and transformation anisotropy along with the newly formed martensite determines the microstress partitioning of the studied CuZr-based alloy. The reversible martensitic transformation is responsible for the pseudoelasticity. The macro mechanical behavior of the pure B2 phase can be divided into 3 stages, which are mediated by the evolvement of the martensitic transformation. This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). [ABSTRACT FROM AUTHOR]

The direct in-situ growth of sensitive materials on the gas-sensing electrode is a subject of great interest for the gas-sensing field. However, combining the device design with the modification of materials is still of great challenge. Herein, a high-performance room-temperature gas sensor was constructed by functionalizing the in situ grown, etched and W-doped ZnO nanotubes (EW-ZnO NTs) with Pt nanoparticles (NPs) on new-type FTO gas-sensing electrode. The effect of etching treatment on the surface characteristics was adjusted by controlling the hydrothermal reaction time to obtain ZnO NTs with uniformly W-doped polycrystalline shells. The thus-produced EW-ZnO NTs sensor was found to be improved by 223 % in response to 10 ppm H 2 S at room temperature compared to the ZnO nanorods (NRs) sensor. Additionally, the effect of different Pt loading amounts on the gas-sensing performance of sensitive materials was investigated. Benefiting from the good contact of sensitive materials and gas-sensing electrodes, the formation of defects and the functionalization of noble metal Pt, the Pt@EW-ZnO NTs gas sensors exhibit numerous superior advantages, including high response, low detection limit (100 ppb) and excellent selectivity. This study shows that the gas detection capability of ZnO sensors can be significantly boosted with the in-situ growth, surface modification and noble metal functionalization, which brings insights into gas sensors. [Display omitted] • The gas sensor was constructed by functionalizing the in situ grown, etched and W-doped ZnO nanotubes with Pt nanoparticle. • Using the synergistic effects of etching, W-doping and Pt functionalization, the sensor can detect H 2 S at room temperature. • The Pt@EW-ZnO NTs gas sensors deliver high sensitivity and low detection limits (100 ppb) to H 2 S gas. [ABSTRACT FROM AUTHOR]

A new method was proposed to pinpoint the compositions with good glass forming ability (GFA) by combining atomic clusters and mixing entropy. The clusters were confirmed by analyzing competing crystalline phases. The method was applied to the Zr–Al–Ni–Cu–Ag alloy system. A series of glass formers with diameter up to 20 mm were quickly detected in this system. The good glass formers were located only after trying 5 compositions around the calculated composition. The method was also effective in other multi-component systems. This method might provide a new way to understand glass formation and to quickly pinpoint compositions with high GFA. [ABSTRACT FROM AUTHOR]

Highlights: [•] An interpenetrating phase composite is synthesized by high energy mechanical milling. [•] Silicon and tin interpenetrate into each other in the composite. [•] The SGM composite shows good electrochemical properties. [•] The lithiation and delithiation reaction mechanism are investigated. [ABSTRACT FROM AUTHOR]

Abstract: The solidification process of the immiscible alloys exhibit a unique opportunity in designing the composites with the spherical crystalline particles dispersed in the amorphous metal matrix. The typical Al–Pb immiscible alloy and the additional elements Ni, Y and Co were selected, and the Al82.87Pb2.5Ni4.88Y7.8Co1.95 multicomponent immiscible alloy has been designed. The ribbon samples of the multicomponent alloy were prepared by using the melt spinning technique. The ribbons were characterized by the scanning electron microscopy (SEM). The phase constitution and transformation were studied by the X-ray diffraction (XRD) and the differential scanning calorimeter (DSC). It was revealed in the as-quenched ribbons the Al-based metallic glass matrix is embedded by the spherical crystalline Pb-rich particles. The microstructure evolution, the glass formation and the thermal stability of the as-prepared composite have been discussed in detail. A method has been developed based on the mechanism of the liquid–liquid phase transformation in the miscibility gap of the multicomponent immiscible alloy to produce the spherical crystalline particles in the amorphous matrix. [Copyright &y& Elsevier]