Facile synthesis of high-purity Ti2SC powders by spark plasma sintering technique

In this work, ternary carbide Ti2SC with high purity was synthesized by a facile spark plasma sintering (SPS) technique with two-step method for the first time. Compared with other methods, SPS required a lower sintering temperature of 1450 degrees C and lower pressure of 30 MPa. The purity and microstructure of Ti2SC can be controlled by the molar ratio of TiS2/Ti/C as precursor. Interestingly, it was found that TiS and TiC were two kinds of important intermediate during the sintering process and thus played a crucial role in the formation of Ti2SC. More importantly, the obtained Ti2SC showed excellent properties including low density of 4.60 g/cm(3), high Vickers' hardness of 6.7 GPa, high fracture toughness (5.4 +/- 0.2 MPa m(1/2)) and flexural strength (394 +/- 10 MPa). Therefore, SPS was a very promising method to synthesize Ti2SC material and could be used in the preparation of other MAX phases.