Property measurements on spray formed Si-Al alloys

A novel Si-Al alloy was prepared by spray forming process for electronic packaging. Property measurements on spray-formed Si-Al alloys after hot pressing were carried out. The results indicate that the alloys (Si-(30%–40%)Al) have advantageous physical and mechanical characteristics, including low coefficient of thermal expansion (6.9×10−6–8.7×10−6/K), high thermal conductivity (118–127 W/(m-K)), low density (2.421×103–2.465×103 kg/m3), high ultimate flexural strength (180–220 MPa) and Brinell hardness (162–261). The alloys are easy to machine to tight tolerances using standard machine tools and they can be electroplated with gold finishes and soldered with Sn-Pb alloy without any difficulty.