Spark Plasma Sintering of MAX Phases and Their Related Composites

Abstract

With the combined merits of both metals and ceramics, including good electrical and thermal conductivity, ready machinability, exceptional damage tolerance, light weight, high rigidity, etc., the ternary layered MAX compounds have attracted much attention in the world. For the synthesis and consolidation of MAX phases, the relatively novel spark plasma sintering (or SPS in short) represents a very competitive technique for its high efficiency and energy saving. Since 2000’s, SPS has been extensively used for this propose, especially in Ti3SiC2 and Ti3SiC2-based composites. The present general results indicate that Ti/Si/TiC is the most appropriate powder mixture and Al is a good aid for the synthesis of high purity Ti3SiC2 by SPS. Various Ti3SiC2-based composites have also been consolidated by SPS and the related properties were improved, such as hardness, strength, fracture toughness and conductivity. It is very important to notice that, Ti3SiC2 phase can also be in situ synthesized in its composites as the commercial Ti3SiC2 powder is hardly available. A few other MAX phases have also been synthesized and consolidated by SPS in one step using various powder mixtures. However, much work should be done to clarify the synthesis mechanism and various processing windows for MAX phases by SPS technique. Lowering the fabrication cost and finding appropriate applications of MAX phases are also eagerly expected.