On the Effect of Chromate Treatment on Tin Coatings for Prevention of Formation of Whiskers

Issue 4(90) 2018
Pages 49-53

N.A. Polyakov, Frumkin Institute of Physical Chemistry and Electrochemistry of
RAS, Moscow, Russia


Keywords: tin plating, chromate treatment, tin whiskers

http://www.doi.org/10.31615/j.corros.prot.2018.90.4-6

 

The work discusses chromate treatment of tin coatings that is recommended in some regulatory documents for prevention of formation of whiskers. It is shown that the surface layer of tin coatings after chromate treatment consists predominantly of tin (II) and chromium (III) oxides and also tin chromates. However, the presence of passive films on the tin surface formed in the course of chromate treatment, just as expected, does not produce any effect on the appearance of whiskers, as this phenomenon is related to the structure of the coating itself