Effect of Spark Plasma Sintering Temperature on Microstructure andMechanical Properties of Ti-45Al-6Nb-0.3W Alloy

Spark plasma sintering of argon atomized Ti-45Al-6Nb-0.3W alloy powders was carried out at different temperatures (1 150, 1 200, 1 250 ℃). The effect of sintering temperature on microstructure and mechanical properties of the alloy was studied. The results show that the spark plasma sintered TiAl alloy consisted of γ and α₂ phases. With increasing sintering temperature, the structure morphology changed from lamellar and equiaxed shape to full lamellar shape, and the grain size and the γ phase content increased. The density of the alloy increased slightly with the sintering temperature, and the hardness changed little. The compression properties of the alloys sintered at different temperatures were better than those of the as-cast alloy. The alloy sintered at 1 200 ℃ showed the best room temperature compression performance with compressive strength of 3 012 MPa and compressibility of 40.8%.