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The (TiZrHfNbTaMo)C‐15 wt.% Co ceramics with excellent comprehensive properties were successfully prepared by vacuum liquid phase sintering. The effects of WC content on the grain size, microstructure, and mechanical properties were investigated. The results showed that WC was dissolved into (TiZrHfNbTaMo)C phase to form a seven‐component solid solution, and the independent WC phase disappeared. The addition of WC improved the wettability between the ceramic phase and the metal phase and promoted the densification of the ceramics. In addition, WC played a role in refining grains and inhibiting the grains growth to a certain extent. The comprehensive properties of ceramics were improved by solid solution strengthening and high entropy effect. When the WC content was 5 wt.%, the toughness reached the maximum of 9.41 ± 0.15 MPa·m1/2, and the hardness of the ceramic with 10 wt.% WC achieved the highest value of 18.18 ± 0.20 GPa. [ABSTRACT FROM AUTHOR]

TiC–Mo–Ni cermets were prepared by vacuum sintering using Ni powder as well as the self-synthesized ultrafine TiC and Mo powders as raw materials. Ni used as sintering additive was added to activate the sintering process. The effects of TiC grain size and sintering temperature on mechanical properties and microstructure of TiC–Mo–Ni cermets were investigated. The results showed that Mo was dissolved into TiC phase to generate (Ti, Mo)C solid solution and form a typical core–rim structure. The grain size of cermets was greatly affected by the particle size of raw material TiC powders. In addition, the increases of oxygen content and grain size in TiC powder were detrimental to the densification of TiC–Mo–Ni cermets. By using the TiC powder obtained under the calcium treatment temperature of 1523 K, the TiC–20Mo–10Ni cermet sintered at 1773 K in vacuum had a high relative density (98.8 pct), uniform microstructure, fine grain size (1.49 μm) and excellent mechanical properties (with the Vickers hardness, fracture toughness, transverse rupture strength of 2081 HV30, 11.43 MPa·m1/2 and 813 MPa, respectively). Moreover, the increase of TiC grain size led to the transition of fracture mechanism from intergranular fracture to transgranular fracture, which was favorable for the improvement of toughness. [ABSTRACT FROM AUTHOR]

This study prepared textured (Ti1/3Zr1/3Hf1/3)B2 medium‐entropy ceramics for the first time that maintain enhanced flexural strength up to 1800°C using single‐phase (Ti1/3Zr1/3Hf1/3)B2 powders, slip casting under a strong magnetic field, and hot‐pressed sintering methods. Effects of WC additive and strong magnetic field direction on the phase compositions, orientation degree, microstructure evolution, and high‐temperature flexural strength of (Ti1/3Zr1/3Hf1/3)B2 were investigated. (Ti1/3Zr1/3Hf1/3)B2 grain grows along the a,b‐axes, resulting in a platelet‐like morphology. Pressure parallel and perpendicular to the magnetic field direction can promote the orientation degree and hinder the texture structure formation, respectively. Reaction products of W(B,C) and (Ti,Zr,Hf)C between (Ti1/3Zr1/3Hf1/3)B2 and WC additive can efficiently refine the (Ti1/3Zr1/3Hf1/3)B2 grain size and promote grain orientation. (Ti1/3Zr1/3Hf1/3)B2 ceramics doped with 5 vol.% WC yielded a Lotgering orientation factor of 0.74 through slip casting under a strong magnetic field (12 T) and hot‐pressed sintering at 1900°C. Furthermore, cleaning the boundary by W(B,C) and introducing texture can enhance the grain‐boundary strength and improve its high‐temperature flexural strength. The four‐point flexural strength of textured (Ti1/3Zr1/3Hf1/3)B2‐5 vol.% WC ceramics was 770 ± 59 MPa at 1600°C and 638 ± 117 MPa at 1800°C. [ABSTRACT FROM AUTHOR]

In this work, high-performance 93W–4.9Ni–2.1Fe–1La2O3 (wt pct) alloy was fabricated by a two-stage sintering method and subsequent vacuum heat-treatment, which had a high densification degree (99.4 pct) and fine grain sizes of W (only 9.76 μm). The utilization of ultrafine W–Ni–Fe composite powder, addition of La2O3 particles and optimized sintering technique effectively resulted in structure refinement. Moreover, the second-phase particles were mainly dispersed at grain boundaries (GBs), besides a small amount of them in the interior of W grains. The as-prepared alloys after sintering first at 1400 °C for 2 hour and then at 1500 °C 30 minutes exhibited enhanced mechanical properties, with a maximum tensile strength of ~ 1024 MPa, elongation of ~ 22.7 pct and hardness of ~ 457 HV1. The excellent strength could be attributed to various mechanisms, namely fine-grained strengthening and oxide dispersion strengthening. Meanwhile, the ductilization is predominantly benefitted from a synergistic effect of low angle grain boundaries, intragranular oxide particles and vacuum heat-treatment process. This work not only promotes the development of oxide-reinforced WHAs for challenging engineering applications but also provides a new perspective for the design of refractory composite materials. [ABSTRACT FROM AUTHOR]

Background and Objectives: The sticky surface of cooked noodles seriously reduces consumer acceptance. This study investigates the effects of 12 wheat flour samples with different farinograph and pasting characteristics on the texture, sensory properties, and surface tackiness of recooked frozen cooked noodles (FCNs). Findings: The recooked FCNs made of flour sample 1# with long dough stability time (DST) and high farinograph quality number (FQN) had a low surface tackiness (411 g) and high evaluation score (87). Meanwhile, wheat flour (sample 12#) with high peak viscosity (PV) had a proper degree of starch gelatinization, which would bring a low surface tackiness to FCNs. FCNs (sample 1#) had a high water‐holding capacity (T21 = 0.14 ms) and low unbound water content (A23 = 1.38%), and they had a dense internal gluten network structure. Conclusions: The dense structure formed by protein and starch contributed to reducing the surface tackiness of FCNs after recooking and storing. Noodles factories should choose wheat flour which has long DST, high FQN, and high PV as raw material when producing FCNs. Significance and Novelty: This study provides important information on choosing wheat flours suitable for making FCNs of high quality. [ABSTRACT FROM AUTHOR]

Herein, CoCrxCuFeMnNi (x = 0, 0.5, 1.0, 1.5, and 2.0, in molar ratio) high‐entropy alloys (HEAs) are prepared through vacuum hot‐pressing sintering. The influences of Cr content on the microstructure and the corrosion behavior in 3.5% NaCl solution are studied. The alloys are mainly composed of two face‐centered cubic (FCC) phases, namely, Cr–Co–Fe–Mn–Ni (or Co–Fe–Mn–Ni)‐rich FCC1 phase and Cu–Mn–Ni‐rich FCC2 phase. With the increase of Cr content, The FCC1‐phase area expands and the FCC2 phase area shrinks. In 3.5% NaCl solution, the corrosion current density (icorr) and average corrosion rate (Vcorr) of the HEAs decrease with the increase in Cr content. The icorr and Vcorr of Cr2.0 alloy are lower at 1.87 × 10−6A cm−2 and 0.02 mm year−1, respectively. The increase of transfer resistance (Rp) and decrease of relative thickness (CPE1−1) of the passivation film indicate that the more difficult it is for ions in the corrosive medium to pass through the capacitor layer, the better the corrosion resistance of the alloy. Improvement of the corrosion resistance is mainly due to the formation of denser Cr2O3 passivation film and reduction of the segregation degree of Cu in the FCC2 phase. [ABSTRACT FROM AUTHOR]

0.7BiFeO3–0.3BaTiO3 ceramics were synthesized through the solid-state reaction method under different calcination temperatures (Tcal) and calcination times (td) to investigate their effects on the microstructure and electrical properties of the ceramics. The grains and phase structure change upon increasing Tcal or td. However, too high values of Tcal or td result in the volatilization of Bi2O3, which deteriorates the electrical properties of the ceramics. For Tcal = 800 °C and td = 2 h, a morphotropic phase boundary with mixed rhombohedral and pseudo-cubic phases appears, and the lowest leakage density and the maximum grain size are obtained, which leads to an improvement in the electrical properties (Pr = 26.7 µC/cm2, EC = 28.5 kV/cm, d 33 ∗ = 237 pm/V, and TC = 419 °C). This study indicates that Tcal and td influence considerably the electrical properties of the 0.7BiFeO3–0.3BaTiO3 ceramics. [ABSTRACT FROM AUTHOR]

It is thought that the sintering of high‐entropy (HE) ceramics is generally more difficult when compared to that of the corresponding single‐component ceramics. In this paper, we report a novel approach to densify the HE carbide ceramics at relatively low temperatures with a small amount of silicon. Reactive spark plasma sintering (SPS) was used to densify the ceramics using powders of HE carbide and silicon as starting materials. Dense ceramics can be obtained at 1600 ‐1700°C. X‐ray diffraction analysis reveals that only non‐stoichiometric HE carbide phase with carbon vacancy and SiC phase exist in the obtained ceramics. The in‐situ formed SiC phase inherits the morphology of the starting silicon powder owing to the slower diffusion of silicon atoms compared to that of the carbon atoms in HE carbide phase. The mechanical properties of the prepared ceramics were preliminarily studied. [ABSTRACT FROM AUTHOR]

We report for the first time the synthesis of a core‐shell structured composite powder with a core of Zr(Ti,Ta)C and a shell of Ti,Ta(Zr)C at 1700°C and investigate the formation mechanism for the core‐shell structure. The medium‐entropy (Ti,Zr,Ta)C ceramics with fine grains (1.1 ± 0.4 μm) and relative density of 94.8% was prepared by hot‐pressing at 2100°C. The flexural strength of (Ti,Zr,Ta)C at 1000°C (493 ± 21 MPa) was close to the room temperature (511 ± 52 MPa). As the temperature increased from 1600°C to 1800°C, the flexural strength was increased significantly, with an ultra‐high flexural strength of 725 ± 32 MPa at 1800°C. The existence of the core‐shell structure in the powder suppressed the grain growth due to the sluggish diffusion effect. The ultra‐high strength of (Ti,Zr,Ta)C ceramics was attributed to its fine microstructures, high fracture toughness, and the reinforced the grain boundary strength. [ABSTRACT FROM AUTHOR]

The AlCrMoZrTi/(AlCrMoZrTi)N multilayer high-entropy nitride ceramic films (HENCFs) fabricated by reactive RF magnetron sputtering presented (200) preferentially oriented FCC crystal structures. With the increase in the modulation period, the nitrogen content and surface roughness of the multilayer films gradually increased, the template effect between the nanocrystalline and amorphous forms was weakened, and the multilayer interface structure decreased. The S4 film with a modulation period of 1500 nm had the highest hardness and modulus (16.6 and 225.7 GPa, respectively) and the highest H/E* and H3/E*2 values. The results of friction experiments showed that the S1 film with the smallest modulation period had a stable friction coefficient and small wear rate on both Si and Cu substrates, and it exhibited the best friction and wear performance due to its low surface roughness, high toughness and compressive yield resistance, and dense multilayer structure. The friction mechanisms of the HECNFs on Si and Cu substrates were mainly adhesive wear, abrasive wear, and a small amount of oxidative wear. [ABSTRACT FROM AUTHOR]

In this article, ultrafine-grained W–Ni–Fe composite with medium W content was successfully fabricated via methods composed of spray-drying, two-stage reduction and low-temperature sintering. It is noticed that the variation of matrix phase fractional volume was effective to tailor the microstructure, mechanical performance and deformation behavior. The microstructure of the medium heavy alloy (MHA) underwent the obvious change from traditional coarsen W grains (>40 μm) to those with sizes of only 3.5 μm, accompanied by a large number of nanosized W precipitate. The two main fracture types of MHA are the W cleavage fracture and matrix phase ductile rupture. The additions of Mo and La 2 O 3 revealed three kinds of strengthening effects, including fine-grained, solid-solution and dispersion strengthening. Experimental results showed that a significant enhancement in tensile properties (∼972.5 MPa and 26.5%) were benefitted from the cooperation of multiple strengthening and plasticized mechanisms, and the detailed effects of deformed twinning and precipitation strengthening were analyzed. The current findings demonstrated that MHA possessed an outstanding combination of strength and ductility and was a promising alternative to conventional tungsten heavy alloys (WHAs) for a more extensive range of applications. • Ultrafine-grained W–Ni–Fe alloy with medium W content was fabricated successfully. • The MHA possessed a superior combination of excellent strength and good ductility. • The interfacial bonding characteristics among W, matrix and La 2 O 3 were analyzed. • The formation process of the transition interfacial layer is elaborated. • The precipitation of nanosized W grains and deformed twin strengthened the MHA. [ABSTRACT FROM AUTHOR]

Ultrafine WC-VC/Cr 3 C 2 composite powders with uniform distribution of V/Cr were synthetized by a novel method composed of carbothermic reduction of the mixture of WO 3 and V 2 O 5 /Cr 2 O 3 at 1050 °C and the following carburization process at 1300 °C under hydrogen atmosphere. The effects of addition amount of VC or Cr 3 C 2 on the phase constitution, particle size and micromorphology of WC-VC/Cr 3 C 2 composite powders were investigated. The results revealed that W, C, V/Cr elements were evenly distributed in the WC-VC/Cr 3 C 2 composite powders. Moreover, the particle size of WC-0.5wt.%VC composite powder was obviously smaller than that of pure WC powder, but decreased slightly with the further increase of VC content. Furthermore, it was found that the inhibition result of Cr 3 C 2 on WC grain growth was significantly worse than that of VC. In terms of micromorphology, pure WC and WC-VC powder had the round shaped WC particles originated from the isotropic growth, while there were triangular prism shaped WC particles because of the faceting of WC particles caused by the minimization of surface energy in WC-Cr 3 C 2 composite powders. Moreover, there were also a few WC particles with the layer-by-layer microstructure owing to the anisotropic growth under the action of Cr 3 C 2. • Ultrafine WC-VC/Cr 3 C 2 powders were prepared by reduction‑carbonization process. • Particle size of WC-VC was obviously smaller than that of pure WC powder. • WC and WC-VC powders had round shaped WC particles resulted from the isotropic growth. • WC-Cr 3 C 2 powder show triangular prism shaped WC particles because of the faceting of WC. [ABSTRACT FROM AUTHOR]

Combining spray drying and in-situ synthesized technology, WC-10Co cemented carbides with uniform composition was prepared by vacuum sintering to investigate the effects of different CeO 2 contents (0 wt%, 0.5 wt%, 1 wt%, 2 wt%, 4 wt%) as well as co-doping with CeO 2 and VC on the microstructure and mechanical properties. With increasing CeO 2 addition from 0 wt% to 0.5 wt%, the WC grain size decreased from 0.79 ± 0.35 μm to 0.62 ± 0.24 μm. The hardness, fracture toughness and transverse rupture strength (TRS) of the alloy with 0.5 wt% CeO 2 all reached the maximum values of 1752 ± 28 HV 30 , 18.50 ± 0.35 MPa·m1/2 and 2245 ± 35 MPa, respectively, which indicated that the mechanical properties of cemented carbide could be simultaneously improved by adding 0.5 wt% CeO 2 to refine the WC grains. However, as the CeO 2 content increased to 4 wt%, the hardness gradually decreased, while the fracture and TRS all slightly decreased first and then tended to be stable. Moreover, the corrosion resistance of alloys first increased and then decreased with the increase of CeO 2 content. The 0.5 wt% CeO 2 alloy had the best corrosion resistance. After adding 0.5 wt% VC, the grain size of alloys became smaller and distribution of Co binder was more uniform. Compared to the samples with only added CeO 2 , the alloy with co-addition of 0.5 wt% CeO 2 and 0.5 wt% VC exhibited the best comprehensive mechanical properties. The hardness, fracture toughness and TRS of the alloy with co-addition of 0.5 wt% CeO 2 and 0.5 wt% VC were 1987 ± 44 HV 30 , 16.10 ± 0.34 MPa·m1/2 and 2023 ± 78 MPa, respectively. [Display omitted] • Ultrafine-grained WC-10Co alloy was prepared by spray drying and in-situ synthesis. • Adding CeO 2 was beneficial to improve the comprehensive properties of the alloy. • The refinement effect of co-doping was better than that of adding only CeO 2. [ABSTRACT FROM AUTHOR]

The effect of temperature on the passive film structure and corrosion performance of CoCrFeMoNi HEA was studied. The results indicated that the passive films exhibited a bilayer structure, where Co and Mo were segregated in the outer film, while Cr was enriched in the inner layer. The content of Fe and Mo species in the passive films decreased with rising temperature, leading to the passive film degradation. The CPT of the HEA was 50–60 ℃. The HEA suffered from selective dissolution of FCC phase below 50 ℃ during the potentiodynamic polarization tests, while pitting corrosion occurred above 60 ℃. • Cr and Mo was enriched in the passive films of the HEA. • Distribution of cation elements within the bi-layered passive films was discussed. • The content of Fe and Mo species in the passive films decreased with raising temperature. • Selective corrosion of the (Cr, Mo)-depleted FCC phase was found. • The CPT value of the HEA was between 50 and 60 ℃. [ABSTRACT FROM AUTHOR]

The Al-27Si alloy was prepared using spray deposition and subsequently incorporated into Mg-Li alloy by vacuum melting furnace to produce a novel Mg-8Li-3Al-0.3Si (LA83–0.3Si) duplex alloy. The effect of final rolling deformation (30%, 40%, 50% and 60%) on the microstructure, mechanical properties, work hardening, and softening behavior was researched. Results indicated that the LA83–0.3Si alloy mainly comprised of α-Mg, β-Li, AlLi, and Mg 2 Si phases. The rolling deformation process induced elongation of the α-Mg and β-Li phase along rolling direction, facilitating the formation of α/β laminar structure, notably enhancing the strength and ductility. Increased final rolling deformation further prompted the formation of the α/β laminar structure and refined the precipitates. Consequently, the LA83–0.3Si alloy's strength progressively increased while elongation slightly diminished. At 60% deformation, the ultimate tensile strength of the LA83–0.3Si alloy reached 331 MPa, with the elongation sustained to 10.9%. The rolling process led to a reduction in the work hardening rate and an increase in the softening rate. With the increase of the final rolling deformation, the work hardening rate decreases and the softening rate further increases. However, the work hardening rate increases, and the softening rate decreases due to the decreasing of the hardness ratio of α-Mg and β-Li phases at 60% deformation. [Display omitted] • The low-sized granular Mg 2 Si phase was formed by adding Al-27Si master alloy prepared by spray deposition to Mg-Li alloy. • The highest strength of the alloy sheet with large final rolling deformation is 331 MPa, and the EL is maintained at 10.9%. • The layer structure weakens the hardening behavior of Mg-Li alloy and improves the softening behavior. [ABSTRACT FROM AUTHOR]

W-Cu immiscible bimetallic composite is an electrically and thermally conductive material with high temperature service potential. In present work, to improve its load bearing capacity, Ti and Zr were introduced to enhance the W-Cu interfacial bond strength and to achieve solid solution reinforcement. By infiltration of Cu-Ti/Zr alloy with different compositions into the W skeleton, both the strength and hardness were enhanced without sacrificing ductility. The Ti/Zr incorporation transformed the incoherent interface of W-Cu to a (W-Ti/Zr)-(Cu-Ti/Zr) semi-coherent interface. By utilizing the EDS technique, significant compositional interdiffusion between immiscible metals was revealed. Moreover, the introduction of Ti/Zr purified grain boundaries by capturing the reactive oxygen to generate TiO 2 and ZrO 2 , which inhibited W-Ti/Zr grain growth by Zenner pinning. As the alloy content rose from 0 wt% to 5 wt%, the average grain size of the W-Ti/Zr (or W) alloy decreased from 2.14 µm to 1.40 µm. It is noteworthy that the alloying with 2.50 wt% Ti reached peak microhardness (417 HV), bending strength (1546 MPa), and ultimate tensile strength (532 MPa). However, the presence of Cu-Ti/Zr solid solution and oxide particles increased the scattering effect of electrons in the Cu matrix, leading to a falling in electrical conductivity. • Well-bonded W-Cu-Ti/Zr alloys were fabricated by skeleton infiltration strategy. • The W-Cu-Ti/Zr alloys possessed high strength and great strain-to-failure. • Second-phase particles affected microstructure and overall mechanical properties. • Multiple strengthening mechanisms of W-Cu-Ti/Zr were analyzed in detail. [ABSTRACT FROM AUTHOR]

Aiming at the refined microstructure and enhanced thermal conductivity of high-entropy carbide (HEC) ceramics for high-temperature applications, the addition effect of graphite was comprehensively investigated in this study. HEC ceramics incorporated with different contents of graphite were solidified by spark plasma sintering (SPS) using self-synthesized high-entropy (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)C powder and graphite as starting materials. The results demonstrate that the incorporated graphite removed the oxygen impurity in the mixed powders, decreased the oxygen content and increased the lattice parameter of the HEC phase, and improved the densification behavior of HEC ceramics. On the other hand, the addition of graphite brings a refinement of HEC grains and improves the mechanical properties. More importantly, the thermal conductivity of the HEC ceramics was significantly increased owing to the removing effect of oxide impurity by the added graphite. It is considered that the lattice "purified" HEC grains with low oxygen content contribute to the improvement in thermal conductivity of the ceramics. [ABSTRACT FROM AUTHOR]

Mo 2 C doped WC-10Co alloys were prepared via an in - situ synthesis method composed of steps of spray drying, roasting, carbothermal pre-reduction and carbonization-vacuum sintering. The effects of Mo 2 C content on the microstructure and mechanical properties of cemented carbides were studied in detail. The results showed that WC and Mo 2 C formed a complete solid solution by the current method. With the increase of Mo 2 C content from 0 wt% to 0.5 wt%, the effects of solution strengthening and fine grain strengthening were obvious, and the grain size was decreased from 0.72 ± 0.32 μm to 0.62 ± 0.27 μm, while the hardness was improved from 1316 ± 20 HV 30 to 1549 ± 14 HV 30. However, the (W, Mo)C solid solution would deteriorate the fracture toughness of the alloys. With the further increase of Mo 2 C content to 9 wt%, the lattice distortion in the solid solution became more serious. Meanwhile, the dissolution of more Mo 2 C in the liquid Co further weakened the dissolution-precipitation process of the solid solution, thus inhibiting the growth of grains and increasing the hardness of the alloys. In addition, with the increase of Mo 2 C content, the dominant fracture mode of the alloy changed from transgranular fracture to intergranular fracture. • Mo 2 C doped WC-10Co alloys were prepared by an in - situ synthesis method. • The addition of Mo 2 C could reduce the grains size. • A complete solid solution of WC and Mo 2 C was formed. • (W, Mo)C solid solution was beneficial to increase the hardness of the alloys. [ABSTRACT FROM AUTHOR]

Molybdenum‑tungsten (Mo W) alloy composed of molybdenum (Mo) and tungsten (W), is a popular high-temperature material. In this paper, a new method for preparing Mo W solid solution alloy has been proposed. To resolve the problem of low extent of solid solution and large grain size, ultrafine Mo W composite powder and Mo-W-Al 2 O 3 composite powder were synthesized by spray drying combined with carbothermic pre-reduction and deep reduction by hydrogen. The results show that the method can effectively promote the formation of Mo W solid solution, and the particle sizes of the four composite powders (Mo-30 W, Mo-50 W, Mo-30 W-0.5Al 2 O 3 , Mo-50 W-0.5Al 2 O 3) were 50–200 nm. After sintering at 1600 °C, all alloys can achieve a high relative density (97%-98%) while retaining a small grain size and good comprehensive properties. Meanwhile, the effect of Al 2 O 3 doping on the sintering performance of Mo W alloys was also investigated in detail. The results showed that doping of 0.5 wt%Al 2 O 3 reduced the grain size of Mo W alloy from 5 μm to 3 μm. In addition, the hardness of Mo-30 W alloy and Mo-50 W alloy were increased to 471 HV and 534 HV, while the bending strength was increased to 612 MPa and 647 MPa, respectively. • A new method for preparing Mo W solid solution alloy has been proposed. • Fine-grained Mo W solid solution alloy was synthesized by currently prepared ultrafine Mo W composite powder. • Spray drying promoted the formation of complete solid solution. • Alloy with 0.5 wt% Al 2 O 3 exhibited excellent bending strength and hardness. [ABSTRACT FROM AUTHOR]

Powder metallurgy approach was used to produce fine-grain tungsten heavy alloys (WHAs), and the effect of Mo addition on the microstructures and mechanical properties of the alloy was discussed. The W-Mo-Ni-Fe ultrafine composite powders were prepared via method consisting of steps of carbothermic pre-reduction and subsequent deep hydrogen reduction. The sintered compacts of these W-Mo-Ni-Fe composite powders reached virtually full densification after sintering at 1500 °C for 2 h. It was discovered that the W grain size of WHAs reduced due to the Mo addition (0, 2.5, 5, 10 wt%). Tensile test results showed that the alloy with 5 wt% Mo exhibited the maximum ultimate tensile strength and elongation, which has a significant relationship with finer W grain size, lower W W contiguity and higher volume fraction of the γ-(Ni, Fe) matrix phase. It was also concluded that the major fracture characteristic of WHAs were transformed from W W decohesion to W-matrix interface separation with increasing the addition amount of Mo. • Fine-grained W-Mo-Ni-Fe alloys were prepared from ultrafine W-Mo-Ni-Fe composite powder. • W grain size decreases with the Mo addition. • Alloy with 5 wt.% Mo exhibited maximum ultimate tensile strength and elongation. [ABSTRACT FROM AUTHOR]

Frozen cooked noodles (FCNs) were prepared with different levels (0, 1%, 3% and 5%) of gluten addition, and the effect of gluten on quality of FCNs was investigated. Cooking properties analysis showed that water absorption ratio and cooking loss of FCNs decreased at first and then increased with the increase of gluten addition. Compared to FCNs with 1% and 5% gluten additions, recooked FCNs with 3% gluten addition had a similar texture property to control sample, and they had the highest tensile force and distance, and the lowest surface tackiness. Meanwhile, the recooked FCNs (3% gluten addition) had smaller pores, denser and more complex gluten network, and their force and elasticity during chewing were the best in sensory evaluation. Low-field 1H nuclear magnetic resonance showed that the lowest T 21 (0.11 ms) and T 23 (51.11 ms) were found in the recooked FCNs (3% gluten addition). Furthermore, the α-helix of samples increased while the β-sheet and random coil decreased, the glutenin macropolymer content of recooked FCNs increased at first and then decreased with adding gluten. These results indicated that the recooked FCNs (3% gluten addition) had a lower surface tackiness, higher sensory scores, and better quality. • Wheat gluten was effective in changing the surface tackiness in recooked frozen cooked noodles. • Wheat gluten could strengthen protein network and tightly wrap starch granules. • Wheat gluten addition formed a denser and more continuous protein-starch network. • Wheat gluten promoted the transformation of protein secondary structure. • Wheat gluten improved the cooking and texture quality of recooked frozen cooked noodles. [ABSTRACT FROM AUTHOR]

In this study, 93 wt.% tungsten heavy alloys reinforced with highly uniform and dispersed ZrO 2 particles were successfully manufactured by powder metallurgy method. In order to fabricate fine-grained tungsten heavy alloys with outstanding performances, ultrafine 93W-4.9Ni-2.1Fe composite powder fabricated using a two-step reduction approach was selected as raw material. Microstructure and mechanical properties were experimentally examined to investigate the influence of ZrB 2 addition. Meanwhile, transmission electron microscope and energy spectral analysis identified that ZrO 2 particles were generated through the reaction between ZrB 2 and oxygen from the grain boundaries. The ultimate tensile strength, elongation, and hardness of 93W-0.75ZrB 2 alloys could reach to 963 ± 16 MPa, 18.4 ± 1.3% and 387.6 ± 4.4 HV, respectively, benefitted from the combination of fine-grained strengthening and oxide dispersion strengthening mechanisms. The W grains without observable texture were homogeneously distributed in the γ matrix phase based on electron back-scattered diffraction analysis. Moreover, it was determined that the main fracture types of 93W-ZrB 2 alloys were W grain cleavage failure and ductile matrix rupture, closely related to the ZrB 2 content in alloys. The current work provided a possible method for purifying the boundaries and enhancing the strength and elongation of W-Ni-Fe alloys simultaneously. • Fine-grained 93W alloys was successfully fabricated by powder metallurgy. • Ultrafine W-Ni-Fe composite powder with a high purity was adopted. • ZrB 2 was added into tungsten heavy alloys to improve the performances. • Strengthening and fracture mechanism of tungsten heavy alloys were analyzed. [ABSTRACT FROM AUTHOR]