First published in the 2012 IPC APEX EXPO technical conference proceedings.
by: Dave Hillman, Tim Pearson; Rockwell Collins, Thomas Lesniewski; Northrop Grumman Corporation
Pure tin is a common finish for copper hook up wire, coaxial cable, ground braid and harness assemblies used on electronic assemblies. Historically there have been fewer reports of whisker growth on tin coated copper wire than on other types of tin coated parts. This paper presents data from humidity- temperature conditioning and electron microscopy inspection of tin coated wire specimens of various size and age. After 4000 hours of 85�C/85%RH conditioning, some of the wires showed tin whisker growth, but the growth was very sparse with near zero density distribution and whisker lengths were typically less than 10 microns. The data indicate very low risk for whisker growth on tin coated copper wire, braid and cable.
SMTA - Surface Mount Technology Association is a non-profit international association of companies and individuals (totalling 4,000) involved in all aspects of advanced electronics assembly, surface mount and related technologies. Membership Info | SMTA Certification | Bookstore