Effect of rare earths on microstructure and properties of Sn/sub 2.0/Ag/sub 0.7/CuRE solder alloy

摘要

In the study the fabrication, microstructure, mechanical and physical properties and wettability of Sn/sub 2.0/Ag/sub 0.7/CuRE solder alloy are investigated. Result shows that when the content of RE<0.1%(mass fraction), RE distributes uniformly in the solder alloy, and the tensile strength and conductance of Sn/sub 2.0/Ag/sub 0.7/CuRE solder alloy are better than those of traditional Sn/sup 37/Pb solder. Its elongation and spreading area are almost equal to that of Sn/sup 37/Pb. When the content of RE reaches 0.5%, RE compounds can be easily found around the boundaries of grains and phases. The tensile strength and elongation and spreading area of Sn/sub 2.0/Ag/sub 0.7/CuRE solder alloy all decrease sharply. Therefore, RE amount added to the Sn/sub 2.0/Ag/sub 0.7/CuRE solder alloy under 0.1% is proper.