Chromate Conversion For Corrosion Resistance

In the chromate conversion process, part of the metal surface is converted to a superficial layer containing a complex combination of chromium compounds.

The chromate film will be soft when freshly formed, but once it gets dried and aged, the layer becomes more rough resistant. Chromate conversion coatings provide excellent corrosion resistance.

Paint, polish, and organic finishes will bond exceedingly well to chromate conversion coatings. Additionally, the chromate coatings will prevent loss of plain adhesion due to under film corrosion.

The most common use for chromating is to impart corrosion resistance to zinc aluminium parts and zinc plated steel.

These films will vary in color depending upon the chemicals being used and the bottom metal being coated. Colors vary from clear, to light shining, to gold.

Greater corrosion protection is given with formulations that gives a golden color, since these coatings tends to be thicker. A multicolored appearance will be obtained when the base metal is non-uniform.

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