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Zinc peels off at bending corners

A plating shop do our plating for us. We plate metal rods 1/4" in diameter and after plating we bend it 90 degrees. All was going well until the last 2 batches of metal we have received. If we bend it after plating the zinc plating peels off. I am trying to help the shop that does the plating for me to solve this problem or to find an additive to prevent the peeling after bending problem.

Thank you in advance for your assistance on the matter.

Hassan Fleifel, P. Eng.
Production - Maadi, Cairo, Egypt
2004

May be zinc layer thicker could you check about thickness, and why you bend the rod to 90 degree ? Because some cases you must form the rod before plating. Remark. The suitable of thickness should be 8-13 microns.

Tawatchai Sujitranuruk
- Thailand
2004

Dear Mr Hassan,

Two reasons could be reason for peel off, adding an additive may not help. 1. Too much brightener : ask your plater to Carbon treat his bath. 2. Improper oil removal before plating : Check the cleaning/pickling cycle.

Regards,

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2004

Mr Hassan.

I agree with Mr. Vahanwala; I think you have to much additive in your solution "booster" try use a carbon treatment.

Regards

Anders Sundman
4th Generation Surface Engineering
Consultant - Arvika,
Sweden
2004