Hello Techniques, Does anyone know a measure of stress (physical tension) exerted on the copper of the barrel of a PTH at various temperatures ranging from -65C to +125C (IPC spec). Specifically the stress on 10 mil drilled PTHs on a .062 board using FR4 material. If there is a mathematical formula (or program) to model these stresses? Secondarily I am interested in comparing the stresses from the various testing procedures. These include but are not limited to Mil-55110 thermal shock, and the Delco test, fluidized sand bed, liquid to liquid, etc. Are there papers detailing the actual stresses the board undergoes, and what failure modes occur. Thanks Rich ------------------------------------------------------------------ Richard Olsen Telephone (602)-232-9154 Continental Circuits Corp. Main (602)-268-3461 3502 East Roeser Road Fax (602)-268-0208 Phoenix Arizona Pager (602)-310-6245 85040-2905 Internet [log in to unmask] USA I make circuit boards,what do you do? ------------------------------------------------------------------ ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## 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. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################