Abstract
Spontaneous growth of metal whiskers,represented by tin whiskers,has haunted tin-based platings and solder joints for decades and caused huge losses to the electronics industry.Despite numerous efforts,the underlying growth mechanism has been resisting interpretation,and the whiskering phenomenon even continues to expand its territory.Here,we report the growth of tin whiskers from a Ti6Sn5 intermetallic.These tin whiskers share similar characteristics with those found on the platings or solder joints,but grow more and faster,with finer diameters.After tin whisker growth,Ti6Sn5 retains its crystal structure,implying a dealloying process.Combining experimental and first-principles calculation results,we ana-lyzed the growth mechanism of tin whiskers in detail,and proposed a diffusion-based growth model.The strain energy stored in Ti6Sn5 during deformation provides a driving force for whisker growth,and the short-circuit diffusion paths generated by such deformation accelerate whisker growth.These find-ings identify the critical role of intermetallic substrate in the whiskering phenomenon,shedding new light for comprehensively understanding the whisker growth mechanisms.Furthermore,the plenty and rapid growth of tin whiskers also means a new method for the preparation of one-dimensional metallic materials.
NETL
NSTL
维普
万方数据