Creep and Creep Rupture Properties of Sn-8Zn-3Bi Solder
Akio TAKADA, Masao SAKANE and Yutaka TSUKADA
Abstract:This paper studies creep and creep rupture properties of Sn-8Zn-3Bi lead free solder. Static tensile creep and creep rupture tests were carried out using the solder at 313K, 353K and 398K. Equations for predicting the rupture time and creep strain of the solder were proposed by analyzing the experimental data. The equations predicted the experimental rupture times within a factor of two and the experimental creep strains within a factor of 1.25. The creep rupture and creep deformation characteristics of Sn-8Zn-3Bi were compared with those of Sn-37Pb, Sn-95Pb, and Sn-3.5Ag solders. Sn-8Zn-3Bi solder had a superior creep resitance to the two Sn-Pb lead and Sn-Ag lead free solders. The relationship between the creep strain rate and relaxation behavior in creep-fatigue test was discussed for the three solders. Key Words:Solder, Creep, Constitutive equation, Rupture time, Electric device, Activation energy