Abstracto

Study of Some Mechanical Properties and Wetting Behavior with Addition Bi to SnCu Solder Alloys

S. Mohammed , A.El-Maghraby

Composition of Sn99.5-xCu0.5Bix has been examined as one of the lead free solder alloys and considered for soldering in electronic packaging. The addition of bismuth to Tin improves the ductility and restrains the fillet lifting, which are problems of lead-free solders with Bi. Melting point of the samples were studied; the addition of Bismuth to SnCu0.5 binary alloy lowers the melting temperature. Wetting contact angle measurements of the Sn99.5 Cu0.5, Sn59.5 Cu0.5Bi40, Sn54.5 Cu0.5Bi45 and Sn49.5 Cu0.5Bi50 rapidly solidified lead free solder alloys on CuZn30 substrate were carried out at 573 K. The internal friction, elastic moduli, microhardness and the microstructure of the as-cast alloys at room temperature have been investigated. The examined physical properties are improved by increasing bismuth contents in the studied lead free solder alloys. These improved properties indicate that these alloys are adequate for low temperature soldering applications