Microstructure and properties of 50Si50Al alloy produced by spray deposition and hot pressing process

A novel Si-Al alloy prepared by spray forming process investigated in this paper. Experimental results show that fine and homogeneous grain structure is obtained in as-deposited alloy. In addition, hot pressing process can eliminate the porosities formed at deposition process. Microstructure analysis show that the primary silicon fractured at a given stress and the particles congregated in microzone with increasing of the stress. After hot pressing, the alloy exhibits well physical and mechanical characteristics, the density is 2.514?g?cm(3), the coefficient of thermal expansion is 10.3???10(?6) K-?1 at the range from room temperature to 100??C, the thermal conductivity can reach 132 W?m(?1)?K-?1, the ultimate compressive strength and Brinell hardness is 97.2?MPa and 130 HB, respectively.