Authors: JongWoong Kim YoungChul Lee SangSu Ha SeungBoo Jung
Publish Date: 2008/02/12
Volume: 20, Issue: 1, Pages: 17-24
Abstract
Failure behaviors of ball grid array BGA solder ball joints under various loading conditions of highspeed shear test were investigated with an experimental and nonlinear 3dimensional finite element modeling work A representative Pbfree solder alloy Sn30Ag05Cu was employed in this study Far greater shear forces were measured by highspeed shear test than by lowspeed shear test The shear force further increased with shear speed mainly due to the high strainrate sensitivity of the solder alloy Brittle interfacial fractures can be more easily achieved by highspeed shear test especially in higher shear speed This was discussed with the relationship between the strainrate and workhardening effect and resulting stress concentration at interfacial regions Shear force decreased with shear height and it could be found that excessively high shear heights unfavorably affected the test results leading to unexpectedly high standard deviation values or shear tip sliding from the solder ball surface
Keywords: