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Hydrogen embrittlement

I am a graduate student starting work on hydrogen embrittlement. I know cadmium plating is used in aircraft, but its toxic. My prof's patented coating - silane might work as a coating ,but I need to find the inhibitor or catalyst which will help in hydrogen recombination so that the molecular hydrogen formed can be baked away. Can anyone give me a clue please?

Thank you,

Karthik Suryanarayanan
- Cincinnati, Ohio
2003

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I don't believe hydrogen recombination is a problem at the temperatures ordinarily used for hydrogen bake-out. That's about all the free advice you can expect for help in development of a patented process.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2003

First, is hydrogen embrittlement a problem on your parts. Yes, there is a small amount of re-embrittlement after bake. I know that there has been a paper or two at the airline plating forum. AESF has a link from this site and they will be happy to sell you any of what they still have copies of. They can also do a literature search for you for a fee.

James Watts
- Navarre, Florida
2003

I know aluminium allows seepage of hydrogen mono-atoms,will an organic coating(such that the hydrogen is blocked) on aluminium substrate be a good alternative for cadmium used in aircraft gears? this' in connection to hydrogen embrittlement.

Karthik Suryanarayanan
- Cincinnati, Ohio
2003

If you are talking about aluminum gears, forget it. If you are talking about an aluminum coating, plating is not economically commercially feasible. IVD or PVD deposited aluminum are options, but they also are more expensive. Aluminum does not have an equivalent natural lubricity and might tend to promote electrolytic pitting. Cadmium plating is not a terrible demon for hydrogen embrittlement IF the parts are in the oven within 15 minutes after coming out of the tank. Also, the acid activation step is normally badly abused and causes far more of a problem and then is covered by the plate.

James Watts
- Navarre, Florida
2003