Influence of Tin Hot Dipping on Mechanical Properties of Copper Alloy for Flat Spring

In this study the effect of newly developed Sn hot dipping process for the surface coating of the copper alloys were examined. The copper alloys tested contain a small amount of Ni and Sn. They have good electrical conductivity and high temperature characteristics and are being used widely for springs in small parts as relays and connecters. Mechanical properties of the hot dipped alloy such as the surface roughness, the spring limit, the tensile strength and Young’s modulus at elevated temperatures were measured. The process resulted in much less degradation of the original Cu alloys than the conventional electroplating.