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Hydrogen embrittlement bake

A lot of specs ask to do hydrogen embrittlement bake of the high strength steel parts within 4 hours after Cr plating. I have a case where the bake was done 12 hrs after the Cr plating. What would be its impact on the part, knowing that high strength steel is susceptible to hydrogen embrittlement. Is there any non-destructive method to prove the part is still good.

Thanks,

Marie [last name deleted for privacy by Editor]
engineer - Ottawa, Ont, Canada
2004

Answer one --They are not to specification, therefore the parts are not acceptable. Now, you are in a nasty process of what will the customer accept. One answer might be to break a number of them to see if they have a required strength. Another approach might be to have a specialty lab do a test for the amount of hydrogen in the part. This is in an unknown and not widely accepted arena, so do not expect that approach to be accepted. It is a long test and very few labs have that equipment, so the cost is high. If the part was grossly over specified for its intended use, there is a possibility that the customer would accept them with another 23 hour bake cycle.

James Watts
- Navarre, Florida
2004