Rust Formation of Hard Chrome Plated Shaft-reg

Q. We have use the rubber wood for stacking the hard chrome plated shaft. After 5 to 6 months the shaft getting fully corroded at the contact portion of rubber wood,but the remaining area found free from corrosion. Can I know the reason for this corrosion? Please explain with details. Hope your positive reply at the earliest.

A. Although Chromium is touted as having "good corrosion resistance", hard chromium as a coating by it self is generally micro-porous. If standard hard chromium is plated directly on a ferrous substrate and subjected to the elements, corrosion can occur. To minimize corrosion of chromium on ferrous alloys, stored parts should be coated in cosmoline or oiled down.

For extreme cases of corrosive environments, a base coating of nickel under the chromium prevents corrosion.

Thank you for the question.

Randy Taylor