High‐Pressure Sintering of Rhombohedral Cr2S3 Using Titanium–Zirconium–Molybdenum Tools

The influence of sintering parameters on the physical properties and the chemical structure of rhombohedral Cr2S3 (rh‐Cr2S3) is investigated using high pressures and high temperatures. The densification of the powder is performed by applying the high‐pressure field‐assisted sintering technique/spark plasma sintering. Using a titanium–zirconium–molybdenum (TZM) alloy as sintering tool, it is possible to increase the magnitude of the applied pressure to several hundred MPa at temperatures as high as 1223 K. A relative density of up to 99.9% is achieved at a sintering temperature of 1223 K and a pressure of 395 MPa. The presence of phase‐pure rh‐Cr2S3 is proven by X‐ray diffraction analysis and transmission electron microscopy. The Seebeck coefficients of the self‐doped samples change drastically with the sintering temperatures ranging between −650 and −350 μV K−1. The densities and the thermal conductivities of the sintered samples increase with increasing sintering temperatures. The electrical conductivity is largely increased compared with the thermal conductivity potentially due to the current‐assisted high‐pressure sintering.

利用高压和高温研究了烧结参数对菱方晶系Cr₂S₃（rh - Cr₂S₃）物理性质和化学结构的影响。通过应用高压场辅助烧结技术/放电等离子烧结对粉末进行致密化。使用钛 - 锆 - 钼（TZM）合金作为烧结工具，在高达1223 K的温度下，有可能将所施加的压力提高到数百兆帕。在1223 K的烧结温度和395 MPa的压力下，实现了高达99.9%的相对密度。通过X射线衍射分析和透射电子显微镜证明了纯相rh - Cr₂S₃的存在。自掺杂样品的塞贝克系数随着烧结温度在 - 650到 - 350 μV K⁻¹之间变化而急剧变化。烧结样品的密度和热导率随着烧结温度的升高而增加。与热导率相比，电导率大幅提高，这可能是由于电流辅助高压烧结。