Effect of Rare Earths on Microstructure and Properties of Sn2.0Ag0.7CuRE Solder Alloy

Abstract

In the study the fabrication, microstructure, mechanical and physical properties and wettability of Sn_2.0Ag_0.7CuRE 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_2.0Ag_0.7CuRE solder alloy are better than those of traditional Sn³⁷Pb solder. Its elongation and spreading area are almost equal to that of Sn³⁷Pb. 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_2.0Ag_0.7 CuRE solder alloy all decrease sharply. Therefore, RE amount added to the Sn_2.0Ag_0.7CuRE solder alloy under 0.1% is proper