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Effect of hydrogen de-embrittlement on plating life

We are a front fork manufacturer. and we do hard chrome plating on a part called inner tube which is a steel tube with 3 mm thickness. We do not process the tube for Hydrogen de-embrittlement after plating. We suffer a heavy warranty due to plating peel off and rusty on plating surface. I would like to know is it because of not processing for Hydrogen de-embrittlement after plating. The plating passes through all CASS test, microcrack test etc without fail whenever checked. Please advise.

Regards,

MADHUKAR SINHA
manager QA Hard chrome plating plant - FARIDABAD, Haryana, India
2004

Hydrogen embrittlement is not the cause of your problem. Plating preparation/plate cycle is the cause. There is a possibility that the tube is flexing more than you think and is causing the chrome to peel. Some destructive testing on some aged parts will give you an idea if this is the case. Hydrogen embrittlement causes the tube to fail, not the chrome delamination. PS, a bake cycle is a good idea for chrome, even when the tube is under Rockwell 39.

James Watts
- Navarre, Florida
2004

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First of two simultaneous responses --

I hope you are referring to the Yamaha Front fork. I have an Enticer having the same problem. Please re-look into your plating bath purity, Recycling frequency, degreasing chemical's effectiveness, degreasing bath purity, stuffs like that.....

V S Magesh
- Chennai
2004

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Second of two simultaneous responses --

Dear Mr Madhukar,

For two wheeler front forks, 15 microns of Duplex Nickel plating followed by 10 microns of Hard Chrome is the industry norm. This should get you past 200 hrs CASS which is the minimum requirement for a tropical monsoon climate such as ours.

Best regards

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2004