Microstructure and property characterization of a spray-deposited 60Si40Al alloy for electronic packaging application

摘要

A novel Si-Al alloy has been prepared by spray forming process applied to electronic packaging. The microstructures and properties of the alloy were studied by using optical microscopy,scanning electron microscopy,coefficient of thermal expansion (CTE) and thermal conductivity (TC) measurements,3-point bending and Brinell hardness tests. The results show that the microstructures of spray formed Si-Al alloy are fine and homogenous,and most of the phases that disperse between the primary silicon phases are supersatu rated a(Al) and Al-Si pseudo-eutectic phases.When appropriate hot pressing process was applied to the as-deposited perform,the po rosities were eliminated basically. After hot pressing,the alloy exhibits well physical and mechanical characteristics,the thermal conduc tivity can reach 127 W/(m·K),the coefficient of thermal expansion is 8.7 ×10-6/K,the density is 2.465×103 kg/m3,the ultimate flexural strength and Brinell hardness is 220 and 162 MPa,respectively.