SRC Forum - Message Replies
Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and Answers
Topic Posted by: Reliability & Maintainability Forum
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Posted by: Tom Donnelly
Date posted: Sun Jan 3 1:59:31 US/Eastern 1999
Subject: Screening solder workmanship
I am currently working with space related hardware. The issues I am having are with solder joint reliability and possible sources for specific failure rate information as it relates to the thermal stress testing of PWB's.
What is the difference in solder joint failure rates when the electronic equipment is exposed to -45F versus -30F?
and what failure mechanism's did I miss by only exposing the equipment to -30F.
I have the same question for taking the equipment to +60F instead of +85F. What is the differnce in failure rates for the solder connections and what failure mechanism's did I miss.
From my many years in Reliability I believe that the difference is insignificant, but my customer's would like me to quantify it....I appreciate any thoughts you could contribute to solving this problem...... T.Donnelly
Subject: Solder Failures and Fatigue
Reply Posted by: Len Stascavage
Naval Surface Warfare Center
Date Posted: Mon Jan 11 14:06:02 US/Eastern 1999
I don't know if this will help you, but there is an interesting article, "Temperature Cycling and Thermal Shock Failure Rate Modeling", Page 10 in the 1997 Reliability Physics Symposium Proceedings. If the article doesn't help, you might fing the references of use.