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Embrittlement after yellow passivation

Q. We are using Zinc plating (yellow passivation) on CRS ( EDD grade) sheet used as drawn can cans. We noticed an embrittlement of the steel after plating. This embrittlement was so bad that when two such products were hit against each other they developed longitudinal cracks (cracks along the axis of the can). Could you pl suggest a cause and a possible remedy.

Thanks,

Arun Bhardwaj
automotive component manufacturing - Gurgaon, Hryana, India
2004

A. Mr Bhardwaj

Please follow this procedure

Plate Zinc
Rinse x 2 times
Nitric acid 1 percent dip. 10 secs.
Dry.
De embrittle at 220 Centigrade for 120 minutes. Check and establish time.
Cool in air naturally.
Activate in 1 % Nitric. After component is cool.
Chromate as needed.

This is the procedure to eliminate Hydrogen Embrittlement after plating. Before Passivation. Good Luck.

Asif Nurie [deceased] [deceased]
- New Delhi, India
With deep sadness we acknowledge the passing of Asif on Jan 24, 2016