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Similar to gluten, zein can form a viscoelastic network upon hydration and shear. This makes zein a promising protein to develop gluten-free bakery products. In this study, the effect of addition of different hydrocolloids (hydroxypropyl methylcellulose (HPMC), guar and xanthan gum), and the inclusion of pregelatinized starch (PG starch) and lactic acid (LA) on zein-corn starch dough and bread properties was examined. The addition of HPMC, and to a lesser extent guar gum, significantly changed the viscoelastic zein dough properties and resulted in bread samples with improved loaf volume and sensory properties. Scanning electron microscopy revealed the formation of a continuous fine foam-like structure in the zein-starch dough when HPMC and guar gum were added. This finer structure translated in a lower dough stiffness and resistance to deformation, and a higher degree of deformation characterized by lower complex moduli and increased creep compliance values. Xanthan gum addition, conversely, had an adverse effect on zein bread loaf volume which was attributed to potential weak repulsion between xanthan and zein molecules. In addition, the amount of α-helix and β-sheet secondary structures in bread samples was altered upon hydrocolloid and PG starch addition and played a role in bread crumb hardness. Overall, the zein bread with HPMC showed textural properties most similar to gluten bread. This research sheds light on different structure levels of zein-based gluten-free recipes as affected by inclusion of hydrocolloids, PG starch and LA, and provides a sound basis for the rational development of zein-based gluten-free breads. [Display omitted] • Zein forms a viscoelastic fibrillar network upon hydration and shear. • Zein-starch (Z-S) systems hold promise for gluten-free bread production. • Hydrocolloid addition alters the viscoelastic dough properties of Z-S recipes. • Hydrocolloid characteristics strongly determine protein structure in Z-S recipes. • Molecular built and microstructure of hydrocolloid Z-S dough relate to loaf quality. [ABSTRACT FROM AUTHOR]

Abstract: TiC reinforced magnesium matrix composites were successfully synthesized by spontaneously infiltrating molten magnesium alloy into Al–Ti–C preforms and in situ forming TiC particles in the liquid of magnesium alloy. Damping capacities of in situ TiC reinforced magnesium matrix composites were investigated. Experimental results show the damping capacity of the magnesium alloy increased with the increase of reinforcement percentage. Improved damping capacities of composites can be attributed to dislocation damping mechanism at room temperature. At elevated temperatures, interface damping becomes a new contributor to the increase of damping capacity. [Copyright &y& Elsevier]

In this paper, high quality Mo-(10–40) wt% Cu and W-(10–40) wt% Cu alloys were prepared by powder metallurgy using the ultrafine molybdenum and tungsten powders as raw materials. The molybdenum powder with the size of 100–200 nm and tungsten powder with the size of 50–100 nm were prepared by a two-step reduction-process composed of an insufficient carbothermal reduction reaction and the following deep reduction reaction by hydrogen. From the experimental results, it was concluded that at the sintering temperature of 1200 °C to 1300 °C, relative densities of the Mo-(10–40) wt% Cu and W-(10–40) wt% Cu sintered blocks can reach >98%, and at the same time, excellent physical and mechanical properties were achieved. Meanwhile, the larger the content of copper in the alloy, the lower the temperature required for densification. At 1300 °C, the relative density, microhardness and thermal conductivity of the Mo-10 wt% Cu and W-10 wt% Cu sintered blocks are 98.83% and 99.36%, 167 HV and 283 HV, 138.38 W·m−1·k−1 and 154.15 W·m−1·k−1, respectively. Whereas, at 1200 °C, the relative density, microhardness and thermal conductivity of the Mo-40 wt% Cu and W-40 wt% Cu sintered block are 99.68% and 98.87%, 150 HV and 207 HV, 138.38 W·m−1·k−1 and 154.15 W·m−1·k−1, respectively. The present method was much more convenient relative to the traditional infiltration method. • Mo Cu or W Cu alloys are one-step prepared by using ultrafine Mo or W powders. • The larger the copper content, the lower the temperature needed for densification. • The prepared alloys have fine grain size, high hardness and thermal conductivity. [ABSTRACT FROM AUTHOR]

Adiabatic foam has been successfully prepared through sintering sodium silicate which is modified by boric acid. The effect of the sintering temperature, boric acid content and modulus of sodium silicate on the thermal conductivity, density, compression strength and microstructure of the adiabatic foam was studied in detail. In the sintering process, B 3+ ion can take the place of the Si 4+ ion by incorporating into the Si–O–Si structure via Si–O–B bridges, increasing the chemical stability of the adiabatic foam. High temperature, low boric acid content and low modulus of sodium silicate can reduce the thermal conductivity, density and compression strength. In order to meet the application of exterior wall thermal insulation, 450–500 °C of the sintering temperature, 18–24 g boric acid per 600 g sodium silicate solution, and 2.5–2.8 modulus of sodium silicate are chosen. The samples with thermal conductivity less than 0.044 W/m·K, density less than 100 kg/m 3 and compression strength more than 0.7 MPa are obtained. [ABSTRACT FROM AUTHOR]

Abstract: An approach of selecting alloying elements to control the size of in situ formed reinforcement in metal melts is proposed. This approach is based on the effect of alloying addition on nucleation of reinforcement predicted by the extended Miedema model and Wilson equation and on growth of reinforcement predicted by diffusion coefficient model. Using this approach, the effect of alloying element addition on the size of in situ formed Mg2Si in (AlN+Mg2Si)/Mg composites is evaluated. The results show that the addition of Ti, V, Mo, Cr, Fe and Mn can delay the nucleation and promote the growth of Mg2Si, while the addition of Ge, Sn, Cu and Zn can promote the nucleation and hinder the growth of Mg2Si. The microstructure of (AlN+Mg2Si)/Mg with the addition of Ti has been investigated based on the theoretical prediction. [Copyright &y& Elsevier]

ZrB 2 -SiC ceramic and Nb were brazed by using a novel high entropy alloy CoFeNiCrCu filler. Interfacial microstructure, mechanical properties and brazing mechanism of the joint were systematically investigated. It was found that the activity of Cr could be maintained during the brazing process due to the high-entropy mixing effect of CoFeNiCrCu. The newly generated Cr 2 B had a tooth shape and it improved interfacial bonding between ZrB 2 -SiC and Nb. A composite microstructure containing a soft FCC and hard Laves phase was formed in the joint due to the presence of Nb and this microstructure significantly enhanced the joint strength. Influences of brazing temperature on the interfacial reaction and shear strength of joint were also investigated. After being brazed at 1160 °C for 60 min, the maximum shear strengths of the joint were 216 and 94 MPa at room temperature and at 650 °C, respectively, indicating the successful use of the filler. [ABSTRACT FROM AUTHOR]

In order to reduce intermetallic compound formations in brazed joints, a CoFeCrNiCu high entropy alloy was invented and employed to braze SiC ceramics. Results show that SiC ceramics were tightly and strongly brazed with the CoFeCrNiCu filler. Microstructure, phase and shear strength were systematically studied for joints brazed at different temperature. Main compositions were identified as high-entropy FCC, Cu(s, s), Si(s, s), and Cr 23 C 6 phases, regardless the brazing temperature differences. After being brazed at 1453 K, the joint reached a maximum shear strength of 60 MPa, much higher than those brazed with conventional AgCuTi filler. Thanks to high entropy effect of CoFeCrNiCu filler, random solid solution turned out in the seam and benefitted joint quality. The successful use of CoFeCrNiCu high entropy alloy as fillers can expand the application range of high entropy alloys and provide a new filler system to braze ceramics. [ABSTRACT FROM AUTHOR]

In order to relieve high residual stresses between ceramics and metals during brazing processes, an AgCuTi/graphene-reinforced Cu foam composite filler was developed and used to braze the ZrB 2 -SiC ceramic and Inconel 600 alloy. Microstructures and shear strengths of the joints were systematically studied. The joints are composed of TiFe 2 , TiCu, TiC, Cu(s, s), Ag(s, s), and Ti 5 Si 3 phases. It is found the addition of graphene on the Cu foam surface can effectively retard diffusions of metal atoms and avoid the collapse of the foam matrix. After being brazed at 900 °C, the joint can get a maximum shear strength of 157 MPa, much higher than those brazed without graphene addition. The high shear strength was investigated in detail and attributed to the integrity of the Cu foam, formation of the TiC and thickness of the reaction layer at the ceramic side. [ABSTRACT FROM AUTHOR]

Abstract In this paper, brazing behaviors between ZrB 2 SiC and Ti 6Al 4V by Cu foam interlayer were studied. The microstructure, formation mechanism, mechanical property and fracture surface of the joints were systematically studied. The results showed that the phases in the joints were α + β -Ti, TiCu, Ti 2 Cu, Cu(s, s), TiC, TiB 2 and Ti 3 SiC 2. An optimum shear strength reached up to 435 MPa at a brazing temperature of 910 °C and holding time of 20 min. Such a shear strength was 90 MPa higher than the one without the Cu foam. The obtained high shear strength of joint was discussed from microstructure and residual stress. With the increase of brazing time, Cu(s,s) gradually disappeared and the content of Ti 2 Cu intermetallic compound increased, which was harmful for the joint. Furthermore, the residual stress of joint with Cu foam was calculated to be 324 MPa, lower than the one without Cu foam interlayer. [ABSTRACT FROM AUTHOR]

To obtain ideal implant materials, we hot extruded Mg-2.0Zn-0.5Zr-3.0Gd solid-solution alloys, and studied extrusion temperature impacts on materials properties. Fine dynamic recrystallized (DRXed) grains (∼5 μm) and elongated coarse un-dynamic recrystallized (unDRXed) deformed grains turned out at the range of 470–490 °C, but changed to bigger ones (∼8 μm) and abnormal growth (30–40 μm) at 490–510 °C. Precipitated phases consist of rod-like (Mg, Zn) 3 Gd particles and newly precipitated Mg 2 Zn 11 rectangles. The alloy extruded at 490 °C meets all mechanical and anticorrosive requirements for biomaterials, thanks to evenly distributed second phases via the solid solution, and the grain refinements through the hot extrusion. [ABSTRACT FROM AUTHOR]

Microstructure evolution and mechanical properties of AISI 316 LN austenitic stainless steel (SS) after cryorolling with different strains were investigated by means of optical, scanning and transmission electron microscopy, X-ray diffractometer, microhardness tester, and tensile testing system. The deformation-induced martensite transition and the deformation microstructure occurred during cryorolling process were always composed of high-density dislocations, deformation twins, and deformation-induced martensites. Following the strain, the dislocation density in deformation microstructure approached saturation state and the volume fraction of deformation twins combined with deformation-induced martensites increased significantly. At the 70% strain, original austenite was transformed into martensite completely. Further increasing the strain to 90% would refine the martensitic lamellae to nanoscale. The deformation degree also led to remarkable increase of the strength and hardness of the cryorolled SS, and drastic reductions of the elongation. Due to the cryorolling, the tensile fracture morphology changed from typical ductile rupture to a mixture of quasi-cleavage and ductile fracture. [ABSTRACT FROM AUTHOR]

The microstructural contributes to understand the strengthening and elongation mechanism in Lanthanum-doped Titanium-Zirconium-Molybdenum alloy. Lanthanum oxide particles not only act as heterogeneous nucleation core, but also act as the second phase to hinder the grain growth during sintering crystallization. The molybdenum substrate formed sub-grain under the effect of second phase when the alloy rolled to plate. [ABSTRACT FROM AUTHOR]

The BiOI/BiOCl composites with high photocatalyitic and adsorption ablities were prepared via a facile ionic liquid assisted ultrasonic method in several hours at room temperature. The BiOI/BiOCl composites with different contents of BiOI can be conveniently synthesized via changing the amount of 1-ethyl-3-methylimidazolium iodide precursor during the preparation process. Microstructures, morphologies, porosities and bandgaps of the as-prepared samples were determined through various experimental methods. A first-principles calculation was employed to explicate electronic structures of the complex. Photocatalytic results suggest that the obtained BiOI/BiOCl composite with 40% BiOI has the highest photoactivity for the degradation of rhodamine-B and quinoline blue under visible light irradiation. All the rhodamine-B and quinoline blue can be degraded in 25 min and 15 min, respectively. To observe the universality of the BiOI/BiOCl, the degradation results of colorless target pollutant (tetracycline) was also investigated. Based on experimental and computational results, origins of the photocatalytic abilities leading to the observed results were proposed. [ABSTRACT FROM AUTHOR]

The surface treatment of Ti80 alloy with different microstructures was performed by laser shock peening (LSP), and the effect of LSP on Ti80 alloy on microstructure and corrosion properties was investigated. After LSP, the surface grains of Ti80 alloy with different microstructures were all refined, microhardness was significantly increased, and compressive residual stress was generated, and both microhardness and compressive residual stress showed gradient change characteristics along the layer depth. The corrosion resistance of Ti80 alloy with different microstructures was improved in both 3.5% NaCl solution and 5MHCL solution after LSP. Before LSP, the corrosion resistance of lamellar microstructure was the best, followed by bimodal microstructure and the worst by equiaxial microstructure, while the corrosion resistance of equiaxial microstructure exceeded that of bimodal microstructure under the combined effect of volume fraction of β phase, thickness of α phase and compressive residual stress after LSP. • A large number of dislocation tangles and deformation twins were formed in LSPed Ti80 alloy. • LSP can effectively improve the corrosion resistance of Ti80 alloys. • Corrosion resistance of untreated Ti80 alloy: lamellar > bimodal > equiaxial • After LSP, corrosion resistance of Ti80 alloy: lamellar > equiaxial > bimodal [ABSTRACT FROM AUTHOR]

Porous anorthite ceramics with low thermal conductivity were successfully prepared using fly ash and gypsum by direct foaming and slip casting method. Effects of dispersant and foaming process on the performance of the porous materials were investigated. The results show adiabatic anorthite ceramics with the highest open porosity (94%) and the lowest thermal conductivity (0.042 W/m K) can be fabricated by adding 10% content of gypsum, 0.8% content of SHMP and using two-step foaming process. High porosity and small pore size are the main factors resulting in the low thermal conductivity. Meanwhile, the thermal conductivity can be predicted with the proportionality coefficient χ obtained by fitting the experimental data based on previous Gong's model. The a and b values in the expression of the proportionality coefficient χ were further discussed. The results show that they are affected by the pore size and distribution, and then the thermal conductivity will change accordingly. [ABSTRACT FROM AUTHOR]

In this work, supersonic fine particle bombardment (SFPB) was applied to modify surface of TC11 alloy and its impacts on microstructure and fatigue properties were systematically studied. The modified surface owned a nanoscale grain structure and a compressive residual stress with an amplitude of −196 MPa. The depth of hardened layer was about 300 μm. Afterwards, high-cycle fatigue behavior of SFPB modified alloy at −30 °C, 25 °C and 150 °C was studied, and the fracture surface, microstructure evolution, residual stress relaxation and microhardness of Ti alloy were characterized. The results show that the fatigue strength of the alloy is significantly improved by SFPB, and the fatigue strength decreases with the testing temperature. The deformation-induced martensite appears in the subsurface structure of Ti alloy tested at 25 °C and 150 °C, and the amount of deformation-induced martensite increases with the fatigue loading temperature. The compressive residual stress field induced by SFPB is relaxed in different degrees during fatigue loading. The degree of residual stress relaxation is the lowest under fatigue loading at 150 °C due to low cycle life. Mechanisms leading to the microstructural evolution and mechanical property variations were also proposed. • Surface nanocrystallization of TC11 alloy can be induced by SFPB. • SFPB can improve the fatigue strength of the TC11 alloy at different temperatures. • Deformation-induced martensite appears in the subsurface layer at 25 °C and 150 °C, but not at −30 °C. • Relaxation degree of residual stress is the lowest after fatigue loading at 150 °C. [ABSTRACT FROM AUTHOR]

Supersonic fine particles bombarding (SFPB) technology opens a new territory for engineering materials towards improved performances. Owing to its merits and emerging applications, 300M steel (tensile strength ≥1800 MPa) was treated with SFPB to create surface gradient nanostructures. The time dependent SFPB process was implemented on various 300M steel surface to investigate the microstructural evolution and mechanical property. 300M steel surface grains were sufficiently refined down to nanometer scale under high energy SFPB. In the subsurface layer, acicular martensite was found to be bent and broken, resulting in the high-density dislocation. At the early stage of SFPB, the impact affected area of 300M steel surface was deepened with increasing SFPB time, and the grains were constantly refined, which further lead to higher strength and improved hardness. However, after longer treatments of more than 90 s, bombardment energy accumulated at 300M steel surface resulted in grain growths and deteriorations of hardness. In particular, the newly formed microcracks substantially reduced the tensile strength. After SFPB treatment, the dimple size of the 300M steel surface fracture decreased significantly, and a large area of cleavage plane appeared, showing typical characteristics of ductile-brittle mixed fracture. • Surface gradient nanostructures of 300M steel has been created by SFPB treatment. • Dislocation motion has been found the dominant nano-crystallization mechanism. • Appropriate SFPB time can improve the mechanical properties of 300 M steel. • Mixed ductile-brittle fracture morphology was observed for SFPB treated 300 M steel. [ABSTRACT FROM AUTHOR]

Controlled cold rolling impacts on microstructure and mechanical properties of the rare earth Ce-modified SAF 2507 super duplex stainless steel (SDSS) are investigated towards a better application and development prospective over the pristine SDSS. Rolling was performed at room temperature with the deformation level in a range of 30%–90%. A large amount of dislocations into the ferrite phase turned out, and their density increased with the deformation. While, emergence of dislocation plugs group, ferrite grains get refined to nanometer scale during the deformation process. In addition to deformed bands within austenite, formation of α′-martensitic phases and significant increment in their volume fraction are detected and attributed to deformation-induced martensitic transformation. Elongation of the ferrite and austenite microstructures along the deformation direction under the action of high strain also resulted in fibers formation gradually. Correspondingly, significant increase in the strength index while decrement in the plasticity index are observed. Moreover, cold rolling deformation not only affects the tensile fracture morphology but also switches it from a typical ductile to a ductile and quasi-cleavage mixed fracture. [ABSTRACT FROM AUTHOR]