Tin whiskers remain a vexing issue for many applications, particularly those in aerospace where a decade is often a fraction of a product’s lifetime. One of the key challenges is finding protective techniques that are effective without being excessive.
Conformal coatings is one of the technologies used to keep tin whiskers from causing short circuits or other problems. Lockheed Martin Missiles and Fire Control has been studying tin whisker mitigation for several years.
Some of these tests have been running for nearly a decade. Test coupons deployed three types of conformal coatings: acrylic, polyurethane and parylene. The copper and tin platings on some test coupons were scratched and bent, while other test coupons were left in pristine condition. Two base metals, Copper C110 and Alloy 42, were used with tin plating techniques designed to encourage tin whisker growth.
Results from the 9.5-year study will be detailed at IPC APEX EXPO, held in Las Vegas March 25-27. Woody will discuss work she did with partner William Fox in one of the technical conference sessions on Thursday, March 27.
Additional presenters in the Reliability – Corrosion and Tin Whiskers session are Dennis Fritz of MacDermid, Michael Osterman of the University of Maryland’s CALCE and Prabjit Singh of IBM.
Filed under: Boards, IPC, Technical, Trade Show Tagged: conformal coatings, IPC APEX EXPO, Reliability, tiin whiskers, tin plating
