Hi Günter, Good to hear from you again. Yes, indeed, we did some work and the industry recommendation is to precondition ageing SJs prior to accelerated reliability testing--fine-grained SJs give fatigue lives about 2- to 3- times longer than coarse grained ones; this is however irrelevant for product, since in a years time the fine-grained structure coarses significantly, Werner Engelmaier ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8d ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################