Effects of protective materials on the sintering properties of Zn4Sb3

High brittleness materials such as ceramics and semiconductors are prone to fracture during cooling. Improving the sintering quality of such materials has been a problem explored by industry and scientific research. Here, the high brittleness semiconductor Zn4Sb3 was prepared by hot-press sintering. It was found that adding protective aluminum sheets with a similar expansion coefficient of Zn4Sb3 can significantly improve the sintering success rate of Zn4Sb3. The density and compositional homogeneity of the Zn4Sb3 were also significantly improved by the addition. The finite element simulation found the greatest increase in density when the thickness ratio of the sintered sample to the aluminum sheet was 1:1. The increase in density is due to the reduced stress during the cooling process and more uniform stress distribution on the sample. The improvement in composition homogeneity is due to the higher thermal conductivity of the aluminum sheets, which results in a smaller temperature difference inside the sample. In addition, the protective effect of the aluminum sheets reduces the volatilization of Zn. Materials with similar melting points have similar thermal expansion coefficients. High-quality sintering of brittle materials will no longer be difficult as long as a suitable sample protection material is found.