Hallo Ingemar, Stree analyses and FE-modeling of solder joints has a long history of not producing much practical information. The reasons are that solder joint loading is dominated by strains, not stresses, and the creep of the solder. That makes stress analysis very complicated and requires assumptions of constitutive behavior. I will be giving a workshop "Practical Design and Prediction Methods for Surface Mount Solder Joint Reliability" at ISHM-Nordic near Oslo on September 21, where your concerns are going to be addressed. Werner Engelmaier Engelmaier Associates, Inc. Electronic Packaging, Interconnection and Reliability Consulting 23 Gunther Street Mendham, NJ 07945 USA Phone & Fax: 973-543-2747 E-mail: [log in to unmask]