Zinc electroplating is also a protective coating against corrosion, blue gray in color, non-toxic, and can be used around food. Zinc plating performs better than cadmium in an industrial atmosphere, but not in a salt atmosphere. A clear Chromate dip is a protective film applied after electroplating, adding corrosion protection. At Sigma, we also use a “silicon dip,” to aid in assembly. Commercial grades of zinc electroplating are typically applied a minimum of 5 microns thick (.0002”). Zinc electroplating with a

Blue Coated Stud Bolts
Coated Stud Bolts
chromate dip must not show base metal corrosion products at 96 hours of salt spray testing per ASTM B117, but may show white corrosion at the edges. Thickness conversion factors: microns x .0394=mils, mils x 25.4=microns, mils x .0254=millimeters, mils x .001=inches