Synthesis of Ti3GeC2 Powders from Ti-Ge-TiC Mixtures by Pressureless Sintering

Abstract Ti 3 GeC 2 compound has excellent electrical and mechanical properties, which can be used as a potential reinforcement for Ag-based electrical contact materials. However, few reports have been addressed on the synthesis of its powders. The present study, therefore, presents a new route to fabricate high-purity Ti 3 GeC 2 powders from Ti/Ge/TiC by pressureless sintering in vacuum. The influence of sintering temperature and Ge content on the powder purity was studied and the optimized conditions are found to be 1550 ℃ and Ti:Ge:TiC=1:1.1:2. In addition, the reaction path of Ti/Ge/TiC was revealed to be three steps: First, liquid Ge starts to react with Ti to form Ti 5 Ge 3 compounds at around 1140 ℃; Then Ti 5 Ge 3 consumes the liquid Ge and TiC to form Ti 2 GeC at around 1200 ℃; Finally, Ti 2 GeC transfers into Ti 3 GeC 2 with the consumption of residual TiC. The present study lays the foundation for the subsequent applications of Ti 3 GeC 2 powders in high performance composites.