Comparison of the interfacial reactions and properties between Ag/Ti3AlC2 and Ag/Ti3SiC2 electrical contact materials

Abstract Ag/Ti3AlC2 and Ag/Ti3SiC2 composites are promising candidates for electrical contact applications. However, it is necessary to clarify the influence of structural stability of MAX phases on the properties of Ag-based composites to further improve their arc erosion resistance. Herein we report the preparation, interfacial reactions, physical properties as well as the arc erosion resistances of these two composites. The interfacial reaction between Ag and Ti3AlC2 by deintercalation of Al from Ti3AlC2 is identified, while that between Ag and Ti3SiC2 is hardly detected. The formation of the intermetallic compound between Ag and the weakly bonded Al element in Ti3AlC2 decreases the reaction enthalpy of Ag and Ti3AlC2 significantly and promotes the interfacial reaction in Ag/Ti3AlC2, which are confirmed by the first-principles calculations. The sintered Ag/Ti3SiC2 shows lower resistivity and hardness than Ag/Ti3AlC2 because of its weak interfacial reaction. Superior arc erosion resistance of Ag/Ti3SiC2 is obtained, resulting from the relatively stable Ti3SiC2 and the lower resistivity of the composite. The present work elucidates the designing and optimizing strategies for Ag/MAX composites.