Prediction of steady-state creep strain rate and rupture life for SnAg-based Lead-free solder joints by SP test

• Published in: International journal of precision engineering and manufacturing Vol. 14; no. 7; pp. 1245 - 1250
• Main Authors: Yang, Zheng-Jie, Yu, Hyo-Sun, Yang, Sung-Mo, Song, Joon-Hyuk, Park, So-Young
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2013
• Subjects: Engineering; Industrial and Production Engineering; Materials Science; Fractured solder joints; SnAg-based lead-free solder joint; Rupture life; Steady-state creep; SP test; Strain rate
• ISSN: 2234-7593; 2005-4602
• DOI: 10.1007/s12541-013-0169-9

This is to predict the equation of steady-state creep strain rate and rupture life of Lead-free solder joints and to observed the fractographies of the surfaces of the fractured solder joints using the SP creep test method. In this research, Sn-4Ag, Sn-4Ag-0.5Cu, Sn-4Ag-1.0Cu and Sn-37Pb solders are used. So as to compare the Lead-free solder alloys with lead(Pb) containing solder alloys. In addition, SP creep tests are held at temperature of 30, 50 and 80¢™C. And the shear stresses used in the research are in the range of 3 to 22 MPa. The microstructure characterization and fractographic analysis of the fractured solder joints are conducted to fully describe the creep behavior of the solder joints. Increasing the testing temperature from 30 to 80°C has some effect on the fracture behavior of ternary SnAgCu solder joints during creep testing. The increased temperature made the joints more vulnerable to the brittle interfacial fracture. In addition, Sn-37Pb solder joint, dimples in the fractured surfaces are much smaller than that of the Lead-free solder joints. Also using the creep data, we obtained a prediction equation of steady-state creep strain rate and rupture life for Lead-free solder joint in this research.