中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 11 No. 6 December 2001 |
behavior in BGA soldered joints
（1. DiamlerChrysler SIM Technology Co, Ltd, Chinese Academy of Science,
Shanghai 200050, P.R.China;
2. National Key laboratory of Advanced Welding Production Technology,
Harbin Institute of Technology, Harbin 150001, P.R.China）
Abstract: The effects of stress triaxiality on crack propagation behavior in the BGA soldered joint were analyzed using FEM method. The computation results verified that stress triaxiality factor has an important effect on crack growth behavior. Crack growth rate increased with increasing stress triaxiality at the near-tip region, which is caused by increasing crack lengths or decreasing solder joint heights. Solder joint deformation is subjected to constraint effect provided by its surrounding rigid ceramic substrate, the constraint can be scaled by stress triaxiality near crack tip region. Therefore, it can be concluded that crack growth rate increased when the constraint effect increases.
Key words: constraint; crack; behavior; joints
