Sherardizing

Sherardizing is a diffusion process in which articles are heated in the presence of zinc dust.  The process is normally carried out in a slowly rotating closed container at temperatures ranging fromm 320 - 500 celsius.

The resultant zinc/iron alloyed coating is subsequently zinc phosphated or chromated, resulting in a clean, passivated, matt grey surface.

The coating closelt follows the contours of the base material and uniform coatings are produced on articles, including those of intricate shapes.  Carbon steels, low alloy steels, sintered steels, malleable grey iron and cast iron are suitable for Sherardizing.  The process does not give rise to hydrogen embrittlement.