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Novel stainless steel/zinc alloy composites are produced by infiltrating ZA8 zinc alloy into rolled 304 stainless steel wire mesh preforms via squeeze casting. Microstructural characteristics of the composite are observed, and the uniaxial tensile properties at different temperatures are investigated. The tensile properties of the composites of sintered preforms are compared with those of the composites of unsintered preforms. The results indicate that the microstructures and tensile behavior of the composites exhibit anisotropy. The tensile strength of the composite in the longitudinal direction is higher than that in the radial direction and increases with increasing wire fraction. The tensile strength and elongation at the maximum stress of the composite are lower than those of the unreinforced ZA8 alloy tested at room temperature. At an elevated temperature, the tensile strength of the alloy is improved but ductility decreases after adding wire mesh with wire fraction more than a certain value. The strength and elastic modulus of the alloy and composites sharply decrease with an increase in testing temperatures. The tensile strength of the composite decreases after sintering preforms. The fracture surface of the composite shows anisotropy in different directions and different morphologies at different temperatures. [ABSTRACT FROM AUTHOR]

Different contents of WC particle‐reinforced 18Ni300 composites are prepared by selective laser melting method, and the tribological properties are comparatively studied before and after solution aging heat treatment. The results show that a part of WC particles are dissolved, and no obvious pore defects appear. With the increase of WC content, the microstructure gradually transforms from cellular and fine columnar α‐Fe martensite to γ‐Fe austenite. After solution aging heat treatment, the phase is transformed into acicular martensite. The grain size significantly decreases, and the Vickers hardness increases. The grain size decreases and the hardness increases with increasing WC contents. For the as‐built composite, the friction coefficient first decreases and then increases, and the wear rate first increases and then decreases with the increase of WC content. With WC content increasing, the wear rate first decreases and then increases. After heat treatment, the tribological properties are improved. The groove of the specimens before heat treatment is deep with large delaminated craters, and the wear mechanism is dominated by adhesive and abrasive wear. The grooves become shallower, and the adhesive trace becomes lighter after heat treatment. The wear mechanism is mainly adhesive wear and abrasive wear, accompanying with oxidative wear. [ABSTRACT FROM AUTHOR]

Metal‐polymer composites can be used to synthesize material properties. A variety of interpenetrating phase composites have been produced by spontaneously infiltrating porous short‐fiber preforms with unsaturated polyester resin under vacuum conditions. Porous preforms are fabricated by compacting and sintering short 304 stainless steel fibers from cutting stainless steel fiber ropes. Tensile experiments are conducted, and fractographs are examined via scanning electron microscopy. The results reveal that the tensile strength, elongation at maximum stress, and elasticity modulus of the IPCs increase with the increasing fiber fractions and exhibit anisotropy in different directions. The tensile strength and elongation at maximum stress are significantly improved compared with the consistent preforms. A nonlinear elastic behavior and sawtooth‐like fluctuation during yield deformation are noted. Compared with the through‐thickness direction, a higher tensile strength and larger elongation at maximum stress are observed in the in‐plane direction. Finer‐diameter fibers can improve the strength and increase the elongation at maximum stress. The tensile fracture surfaces show a mixture of brittle and plastic fracture characteristics. [ABSTRACT FROM AUTHOR]

Novel stainless steel porous twisted short fiber materials (PTSFMs) with spatial composite intertexture structure are produced by compaction following with sintering of twisted short fibers. The stainless steel twisted short fibers are fabricated using a cutting stainless steel fiber ropes method with a self-developed rotary multi-cutter tool. The porous structure of the stainless steel PTSFMs exhibits a large difference in the through-thickness and in-plane direction, which results in differences in compressive behavior. During the compressive process, it is determined that the stainless steel PTSFMs exhibit typical elastic-plastic behaviors (three deformation stages) in the in-plane direction, but in the through-thickness direction, entered the compact densification zone after short-term nonlinear elastic deformation without a plastic platform stage. The compression deformation resistance in the through-thickness direction is obviously stronger than that in the in-plane direction at a given porosity. The compression strength and the anisotropy both decreased with increased porosity. The compression properties are anisotropic, which also result in different energy absorption efficiencies of the two directions. The relationship between the porosity and the energy absorption efficiency is not monotonically increasing or decreasing, but with the change of porosities, there is an optimal porosity, which has relatively high-energy absorption efficiency. [ABSTRACT FROM AUTHOR]