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The effects of non‐thermal plasma (NTP) on the physicochemical properties of wheat flour and the quality of fresh wet noodles (FWN) were investigated. The results showed that NTP effectively decreased the total plate count (TPC), yeast and mould count (YMC) and Bacillus spp. in wheat flour. Wet gluten contents and the stability time reached the maximum when treated for 20 s. The viscosity of starch increased significantly after treatment due to the increased of damaged starch. The contents of secondary structure were altered to some extent, which was because that the ordered network structure of gluten protein broken. Furthermore, compared with the control, texture properties of FWN were enhanced significantly at 20 s, and the darkening rate of FWN was greatly inhibited due to the low polyphenol oxidase (PPO) activity. Consequently, the most suitable treatment was 500 W for 20 s, providing a basis for the application of NTP in flour products. [ABSTRACT FROM AUTHOR]

Summary: Starch botanical origin is a key factor for the characteristics of Pickering emulsion. Starches with different sizes from rice (2.9–7.6 µm), waxy corn (9.3–25.0 µm), wheat (11.4–33.7 µm) and potato (24.4–54.1 µm) were esterified by octenyl succinic anhydride. The modified starch particles were used as stabilisers to produce oil‐in‐water Pickering emulsions. The physical stability, microstructures and rheological properties of different emulsions were compared. Results indicated that the emulsion stabilised with rice starch particles had the minimum droplet size of 83.6 µm and best physical stability during 30 days of storage. Moreover, starch particle size was negatively correlated with emulsion stability (P < 0.05). The particles (3.85% of the emulsion, w/w) built up wall‐like structures around oil droplets, which prevented them from freely moving. All emulsions showed pseudoplastic fluid behaviours and presented gel properties, but elastic modulus (G′) and loss modulus (G″) were mainly affected by starch botanical origins. [ABSTRACT FROM AUTHOR]

The studies are focused on the complexions in the WC-Co cemented carbides, which represent the phase-like interfacial state at the WC/Co interfaces. A series of experiments were designed to investigate the formation, growth and transformation behaviors of the complexions. It was found that the complexions with cubic structure can be stabilized by quenching or by dissolution of specific elements added in form of carbides as grain growth inhibitors. The characteristics and stabilization conditions of the complexions, as well as their influences on the interfacial structures and mechanical properties of the cemented carbides, were studied in detail for additions of various inhibitors such as VC, Cr 3 C 2 , TiC, TaC and NbC. The results disclose that the existence of complexions is dominated by their formation energy and misfit at the interface between the complexion and WC. The stabilization of complexions, on one hand, inhibits WC grain growth effectively, on the other hand separates the bonding of WC and Co, thus causes decrease of the resistance against intergranular fracture of the cemented carbides. It is proposed that tailoring the stability of complexions by matching inhibitor and carbon content can lead to both the high fracture toughness and high strength of the cemented carbides. [ABSTRACT FROM AUTHOR]

Highlights: [•] Pickering emulsions stabilized by different rice starch particles were prepared. [•] Emulsion stability and microstructure of the Pickering emulsions were investigated. [•] The Pickering emulsions were stable during the 100days of storage. [•] Starch particles accumulated at O/W interface in the form of densely packed layer. [•] Emulsification of rice particle-stabilizer has no correlation with amylose content. [ABSTRACT FROM AUTHOR]

Nanocrystalline WC–Co bulk was prepared using a novel route that combined in situ reactions and subsequent spark plasma sintering. The microstructure was characterized by transmission electron microscopy-based precession electron diffraction technology. The nanocrystalline microstructure has a high WC grain contiguity. The fraction of Σ2 boundaries increases with a decrease in WC grain size. The effect of microstructure on the mechanical properties was analyzed in terms of the correlations between Co distribution, Σ2 boundary fraction and WC grain contiguity. [Copyright &y& Elsevier]

Abstract: Single-phase Mn3Cu0.5Ge0.5N bulks were prepared by spark plasma sintering (SPS) in nitrogen atmosphere at different sintering temperatures, and the effects of sintering temperature on microstructure, nitrogen deficiency and densification were studied. It was found that the densification is accompanied by the thermal decomposition of Mn3Cu0.5Ge0.5N. Nitrogen deficiency and porosity due to the thermal decomposition of the compound do not increase with increase of the sintering temperature; the nitrogen deficiency from decomposition is compensated by the diffusion of nitrogen atoms from the N2 atmosphere. When the two processes reach the balance, minimum nitrogen deficiency of Mn3Cu0.5Ge0.5N is achieved together with the highest densification. [Copyright &y& Elsevier]

Abstract: The WC–Co cermet bulks were prepared by spark plasma sintering (SPS) using powder mixtures with different-scaled WC particles. The SPS densification process was studied by calculating the current distribution between the powder sample and the die in the SPS system. The microstructures were characterized and compared for different samples by the WC grain size, Co mean free path and contiguity of WC grains. In spite of a weak effect of WC particle size on the SPS densification stages, the WC particle size plays a significant role in the homogeneity of the cermet microstructure. Good mechanical properties of the SPSed cermet were obtained with an optimized WC and Co particle-size combination. The effects of scale combination of WC and Co particles on the microstructure hence the properties of the SPSed cermet were discussed. [Copyright &y& Elsevier]

Abstract: The ultrafine-grained ζ-Mn2N0.86 compound bulk was prepared by a novel method that combined the solid-gas reaction, ball milling and spark plasma sintering. Characterizations on the magnetic properties showed that the Néel temperatures of the ball-milled powder and the ultrafine-grained bulk of Mn2N0.86 compound are drastically reduced as compared with the coarse-grained polycrystalline ζ-phase Mn-N compounds. Furthermore, it was found that the antiferromagnetism and the weak ferromagnetism coexist in the ball-milled powder and the ultrafine-grained bulk of Mn2N0.86 compound. [Copyright &y& Elsevier]

Abstract: The nanoparticles and nanocrystalline bulk of pure gadolinium (Gd) were prepared by a novel route. The nanostructures of the single particle and the bulk of Gd were investigated, and the crystal structure was characterized. The fundamental properties, namely the physical, thermal, and mechanical characteristics, were studied for the prepared Gd bulk with an ultrafine nanograin structure. As compared with the conventional polycrystalline metal, the ultrafine nanocrystalline Gd has greatly enhanced functional and structural properties. The physical background for the changes of the fundamental properties with the reduction of the grain size to the nanoscale was analyzed. [Copyright &y& Elsevier]

Abstract: A spheroidization processing has been designed for the forged ultrahigh carbon steels (UHCSs) containing Al, in which the mechanism of the divorced eutectoid transformation is applied. Guided by the CALPHAD calculations, the processing is carried out by two periods consisting of austenization at an intermediate temperature in the three-phase(γ+α+cementite)-zone and then isothermal annealing at a temperature a little lower than the critical temperature at which the austenite decomposes completely. The desired microstructure with the fine spheroidal carbides dispersed on the ferrite matrix has been observed, and the well combined mechanical properties, such as the tensile strength S b =1050MPa, the yield strength S s =740MPa, the elongation ratio δ 5 =14% and the reduction of cross-section ψ =22%, are achieved. [Copyright &y& Elsevier]

The preparation and the mechanism study of bulk pure rare-earth metals with amorphous and nanocrystalline structures, which were produced by spark plasma sintering (SPS), were carried out in this paper. With different processing parameters, the amorphous, two phases of amorphous and nanocrystalline, and complete nanocrystalline microstructures have been obtained. The nano-grain sizes in the bulk nanocrystalline materials are found smaller than the original powder particles sizes, which may change the conventional viewpoint that the grains in the sintered bulk are generally coarser than the raw powder particles. The technique developed in the present work can be extended to the preparation of many other nano bulk metal materials, and thus enables the studies of the nano-size effects on the physical, chemical and mechanical properties of bulk nano materials. [ABSTRACT FROM AUTHOR]

Examines the image simulation and simulation for microstructure in two-phased material on physical basis. Veracity of simulation algorithm using theoretical analysis; Efficiency of computer simulation for science research; Observation of microstructure and evolution in dimensions.

In contrast to the general assumption that the WC1−x phase is stable only at temperatures above 2500°C, in the present study WC1−x is discovered to exist stably at room temperature in nanocrystalline cemented carbides. Based on characterization of the microstructure, crystallographic features and orientation relationships, the formation mechanism for the WC1−x phase in the nanocrystalline structure is proposed, and the conditions of the surface energy and composition are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Complicate preparing procedure of ultrahigh carbon steels (UHCSs) greatly limited their practical application in industry. In the course of searching a simple method for the preparation of the ultrahigh carbon steels, we found a fully fine pearlite microstructure formed in the Al-added steel with high carbon content. Our results proved that the steel can be directly spheroidized into uniformly distributed fine carbides, and that the steel with fine spherodized carbides showed high tensile strength of 1010 MPa and high yielding strength of 650 MPa, together with good elongation of 12.8%. [Copyright &y& Elsevier]

It is very challenging for 3D printing based on the selective laser melting (SLM) technology to obtain cermet bulk materials with high density and homogeneous microstructures. In this work, the SLM process of the cermet powders was studied by both simulations and experiments using the WC-Co cemented carbides as an example. The results indicated that the evolution of the ceramic and metallic phases in the cermet particle during the heating, melting and solidification processes were all significantly inhomogeneous from atomic scale to mesoscale microstructures. As a consequence, the microstructural defects were caused intrinsically in the printed bulk material. The formation and growth of the bonding necks between the particles were mainly completed at the later stage of laser heating and the early stage of solidification. Both simulations and experiments demonstrated that thin amorphous layers formed at the ceramics/metal interfaces. This work disclosed the mechanisms for the evolution from the atomic scale to microstructure during the SLM printing of cermet powders, and discovered the origin of the defects in the printed cermet bulk materials. [ABSTRACT FROM AUTHOR]

A novel binderless tungsten carbide bulk alloyed with Re was prepared for the first time. The formation of solid solution of Re in WC was demonstrated by detailed microstructural and chemical analyses. The Re alloyed WC has very high indentation modulus and nano-hardness of 771 GPa and 36.0 GPa, respectively, which increased by 38% and 52% respectively as compared with those of the conventional tungsten carbide. The mechanisms for the hardening of the (W,Re) C solid solution were analyzed by the first-principles calculations. It indicated that alloying Re can increase the charge density and occupy more bonding states of WC, leading to strong chemical bonds hence high hardness. The present results show the feasibility of solid-solution hardening for WC to obtain even higher hardness. It thus provides a new approach to improve the mechanical properties of cement carbides by tailoring the composition and features of the hard matrix. [ABSTRACT FROM AUTHOR]

Functionally graded metallic materials (FGMMs) are a new type of heterogeneous materials composed of polymetallic components with gradients in structure or composition. Compared with conventional homogeneous materials, FGMMs are able to integrate multiple distinctive components in a spatially controllable manner, thereby creating a combination of various advanced properties that are in theory impossible to be simultaneously possessed by a single material. As a result, FGMMs are highly demanded in complex and harsh working environments such as aero engines (extreme temperature & pressure), water reactors in nuclear power plants (high pressure & corrosive), and space stations (low pressure/temperature & ion bombardment). Despite of the great advantages, the preparation of FGMMs by powder metallurgy, centrifugal casting and other conventional techniques can be very challenging, as those methods lack the ability to precisely tune the composition and structure of materials in 3D space. As an advanced manufacturing technology, additive manufacturing (AM) features rapid prototyping, high utilization rate of raw materials, and a great shaping capability, which opens up huge opportunities for the preparation and development of FGMMs. As of today, the fabrication of libraries of FGMM products including bone plates, engine parts and the shield of spacecraft has been enabled by two major AM approaches, namely directed energy deposition and powder bed fusion. This article reviews the most recent progresses on the additive manufacturing of FGMMs by introducing the classification and design methods of FGMMs, detailing the mainstream AM technologies for FGMMs, and discussing potential applications of various FGMMs. Insights on the challenges and future research directions for the preparation of FGMMs by AM technologies are also presented. By bridging scientific principles, AM technologies and material properties, this article provides not only a guideline on how to obtain desired FGMMs in a demand-oriented fashion, but also a perspective of the potential evolution in this area. The content will be found helpful for general readers who want to learn about FGMMs and researchers in this field to prepare for their future research. • A comprehensive summary on major advances of functionally graded metallic materials. • Details on state-of-the-art design tools and additive manufacturing technologies. • The first composition guided discussions on the applications of FGMMs. [ABSTRACT FROM AUTHOR]

Abstract A novel strategy to prepare W–Cu nanocomposite powder with WC nanoparticles for strengthening was proposed. The feasibility and mechanisms of the present in-situ reactions method for synthesizing multicomponent powders were demonstrated by both thermodynamic calculations and experiments. The W-Cu-WC nanopowder can be prepared at a low temperature with pure phase constitution and homogeneous microstructure with a mean particle size of 60 nm. Owing to in-situ reactions, the orientation relationship of WC and W is formed, which facilitates strong bonding between the strengthening particles and matrix. The new method is applicable to synthesize a variety of composite powders with tailorable phase and particle size. Highlights • A novel strategy to prepare W-Cu-WC nanocomposite powder was proposed. • The feasibility and mechanisms of the in-situ reactions were investigated. • Phase constitution and particle size can be controlled by low temperature synthesis. [ABSTRACT FROM AUTHOR]

The WC-Co cemented carbides with ultracoarse and ultrafine grain structures were tested by the bonded interface technique to investigate the deformation behaviour of WC. The electron backscattering diffraction assisted trace analysis and transmission electron microscopy were combined to examine the microstructural details in the deformation region. It was found that the plastic characteristics of the ultracoarse WC originate from both the prismatic (e.g. {10 1 ¯ 0} ⟨ 1 ¯ 2 1 ¯ 3⟩) and pyramidal (e.g. {0 1 ¯ 11} ⟨0 1 ¯ 10⟩) slip systems. The deformation mechanisms of the ultracoarse and ultrafine cemented carbides were compared. It was proposed that different from the ultrafine cemented carbides in which the plastic deformation is mainly attributed to the metal binder, the dislocations and stacking faults in WC make significant contributions to the plastic deformation hence the fracture toughness of the ultracoarse cemented carbide. [ABSTRACT FROM AUTHOR]

A novel method was proposed to achieve uniform dispersion of ZrO 2 nanoparticles in the WC matrix. The prepared WC-ZrO 2 ceramic exhibited outstanding mechanical properties with simultaneously high hardness and fracture toughness. It was disclosed that the high toughness of the present WC-ZrO 2 ceramic results from the contributions of stress-induced phase transformation from t-ZrO 2 to m-ZrO 2 , the homogeneous ultrafine microstructure with coherent WC/ZrO 2 interface, and the stress release of WC in the vicinity of ZrO 2. The later two factors enhance the fracture toughness by crack deflection and crack bridging. In particular, the contribution to toughness by phase transformation of ZrO 2 is 1.9 and 2.7 times of that of the crack deflection and crack bridging, respectively. This study provides a strategy to increase toughness of ceramics greatly while keeping its high hardness. • A novel method was established for uniform dispersion of ZrO 2 nanoparticles in WC. • Outstanding comprehensive properties of the prepared WC-ZrO 2 were achieved. • Toughening mechanisms were disclosed by microstructural analysis and calculations. [ABSTRACT FROM AUTHOR]

The nanocrystalline Sm 5 Co 19 based alloys were firstly prepared, with Fe, Ni and Nb as doping elements. The microstructure, crystal structure and magnetic properties at room temperature and high temperatures were studied for the nanocrystalline alloys, and the effects of doping elements on the microstructure and magnetic performance were analyzed. It was found that Ni, Fe and Nb doping facilitated transformation from rhombohedral to hexagonal structure of the nanocrystalline Sm 5 Co 19 based alloys. The nanoparticles with the hexagonal structure enhance the coercivity of the nanocrystalline alloys. At high temperatures, as compared with the binary Sm 5 Co 19 alloys, the dispersed nanoparticles containing Fe and Ni increase both the coercivity and saturated magnization, from which good high-temperature magnetic performance of the nanocrystalline Sm 5 Co 19 based alloys were obtained. The results may facilitate development of new type Sm-Co alloys with high magnetocrystalline anisotropy and good high-temperature magnetic performance. [ABSTRACT FROM AUTHOR]

Abstract: A series of Fe–xCr cored wires (x =15, 20, 25, 30, 35 and 40% in weight) were used to produce protective coatings for components used in high-temperature environments by wire-arc spraying. The microstructure, morphology and high-temperature oxidation behavior of the Fe–xCr coatings were investigated. The Fe–xCr coatings presented a homogeneous structure with thin oxide inclusions and low porosity. Thermogravimetric analysis was used to evaluate the high-temperature oxidation behavior of the coatings at a temperature of 650°C under cyclic oxidation conditions. The results showed that all the Fe–xCr coatings exhibited significantly lower weight gain than the uncoated substrate. As Cr content of the coatings increased, the thickness of oxide scales decreased and oxidation resistance improved. [Copyright &y& Elsevier]

• WMo particles were introduced into WCu as the second phase in nanoscale. • Copper matrix grains were refined after the introduction of WMo nanopowders. • Excellent mechanical performance of the W-Cu-Mo alloy has been achieved. • Strengthening mechanisms in the WCu with WMo nanoparticles were revealed. • WMo nanoparticles exhibited significantly improved arc dispersion effect. In this work, WMo nanopowders synthesized by combined sol-gel and hydrogen reduction with the mass fraction of 10% have been added into the WCu alloy to tailor the microstructure and properties of the WCu pseudo-alloy. The electrical properties, thermal properties, tensile and arc erosion behaviors of the infiltrated alloys have been systematically investigated. The microstructure, grain size and phase constitution, as well as the electronic transfer of WMo solid solution were identified by SEM, XRD, EBSD and DFT calculation. The resulted WCu alloy doped with 10 wt%WMo showed enhanced tensile performance and highly improved arc dispersion effect. The mechanical strengthening and arc ablation mechanisms originating from the addition of WMo nanopowders were also discussed. [ABSTRACT FROM AUTHOR]