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In this study, a Sb2S3–Cu2S composite was synthesized by adding Cu2S, which exhibits a negative Poisson’s ratio in a two-dimensional structure, to improve the mechanical properties of the Sb2S3 compound semiconductor. The sol–gel method was used for the preparation of Sb2S3 precursor solution and after mixing synthesized by heat treatment at 260–280 °C. Cu2S growing in a plate-like structure with the Cu2S powders prepared by performing a sulfurization of Cu using polysulfide, it was spin-coated on gold-coated FTO glass substrates. Finally, the Cu2S powders were chemically combined with Sb2S3 pillars to grow in the form of cudgels with acicular structures attached to the pillar structure. The acicular structure attached to the surface of the Sb2S3 pillar structure was observed to be calcostibite (CuSbS2). The mechanical energy absorption of the bare Sb2S3 pillar and Sb2S3–Cu2S cudgels structures was measured through nanoindentation experiments of flat-top tip with a diameter of 2 μm. It was observed that the external energy absorption (energy dissipation) ability of the Sb2S3–Cu2S cudgels structure was improved by more than five times which was compared to the bare Sb2S3 pillar structure.

In this paper, the effect of Rh content on the mechanical properties of Ir-Rh alloys was investigated based on the first-principles of density functional theory.The calculation results show that the strength and hardness of Ir-Rh alloy increase rapidly with the increase of Rh content, reach the maximum value at Ir-10 Rh, then drop rapidly to Ir-40 Rh, then slowly increase and then decrease slowly.The addition of Rh can cause the embrittlement of iridium-rhodium alloys, and its brittleness first increases and then decreases with the increase of Rh content, and reaches the highest at Ir-50 Rh.Considering the results obtained from theoretical calculations and experiments, Ir-20Rh was selected as the alloy composition for the study of hot isostatic pressing technology.The effects of mixing time, whether to mix powder with balls, and degassing temperature on the properties of metal powders were studied to find the best mixing and degassing process parameters.In the experiment of mixing powder of iridium and rhodium alloy, it is found that the time required for mixing powder with balls to reach uniformity is shorter than that without balls.The oxygen content of the final mixed powder obtained by the two processes is equivalent.The nitrogen content of the metal powder mixed with the ball is slightly higher than that without the ball, but it can be reduced to below 0.001% after the degassing process.During the sintering process, with the increase of temperature, the mutual diffusion speed between iridium powder and rhodium powder increases, the sintering neck grows, the internal pores decrease, and the density of the sintered body increases.

In this paper, the chemical vapor deposition (CVD) method was used to prepare Nb-W binary alloys on Mo substrates for the first time. The influences of the process parameters on the composition, average deposition rate, and average deposition efficiency of the Nb-W alloys were studied by orthogonal experiments. Nb-W alloys with W contents ranging from 0.33% to 50.48% were successfully prepared. The mechanical properties and fracture morphologies of the Nb-W alloys prepared by the CVD method (CVDNb-W alloys) were tested by metallographic microscopy, scanning electron microscopy, electron probe analysis, and in-situ tensile tests. The results showed that the Nb-W alloy prepared by the CVD method had uneven macroscopic distributions of Nb and W.The substrate temperature had the greatest influence on the lateral composition gradient, and the H2 flow had the least influence. The influence of the Cl2 flow through the Nb and W on the average deposition rate was also examined. The chlorination temperature of W had the least effect on the average deposition rate, and the average deposition efficiency decreased with the increase in the gaseous chloride ratio of W. The effects of other factors on the average deposition efficiency showed different degrees of wave dynamics. The metallographic observation of 16 samples showed that except for samples 3# and 4# (in which the mass percentages of W were less than 1%), the microstructures of the other samples (in which the mass percentages of W were all more than 1%) showed similar microstructures with layered structural features. Comprehensive analysis of the sample and inverse pole figures revealed that the (101) textural component mainly existed in the CVDNb-W alloys.