TEST PROCEDURE FOR HYDROGEN EMBRITTLEMENT IN PLATED FASTENERS
Q. I am working in a Automobile manufacturing co.( Light Comm.Vehicle ). We want to know how to test Hydrogen embrittlement in case of plated Fastness, which are being used in critical area like Wheel hub bolts, nuts and engine component like Bolt crank shaft etc. We usually test by over-torquing the component. Is there any chemical test which can detect hydrogen embrittlement in case of plated component as on receipt stage of supply. Would any one help in this regard.
Would like to thank you in advance for sparing your valuable time and suggestion.
First of two simultaneous responses (2001)
A. Arun, there are no procedures to chemically detect hydrogen embrittlement. The most common method is to process tensile specimens, such as those identified in ASTM F519 [link by ed. to spec at TechStreet] , through the plating process and then have them tested under sustained load for a given amount of time. Most aerospace applications require a sustained load of 75% of the materials tensile strength for 200 hours.
Best of luck to you.Ira Donovan, M.S.F.
Kansas City, Missouri
Second of two simultaneous responses (2001)
A. There is no chemical test for this. The only thing that I have ever heard of was a very high priced unit that operated at an extreme vacuum and actually measured the amount of hydrogen. It cost too much and was fairly difficult to use plus there was no universally accepted amount as what was bad and what was good. You are stuck with doing notch bar testing which is very time consuming.James Watts
- Navarre, Florida
A. I agree the ASTM F-519 is standard test for hydrogen embrittlement relief. I suggest you double check your source that the notched tensile test bars are properly machined (crush ground) and that you process them exactly as you process the fasteners in question...including all pre- and post cleaning (chemical and / or mechanical) and thermal processing to assure the samples represent the processed fastener.Douglas A. Hahn
Performance Review Institute (NADCAP) - Mason, Ohio
A. Nosotros realizamos un ensayo, que consiste en introducir la tornilleria tratada en una probeta con Parafina , que posteriormente llevamos a su punto de fusion; con la temperatura de calentamiento, el "posible" Hidrogeno ocluido en la pieza saldra al exterior y se detectaran las burbujas retenidas en la parafina, en el caso de haberlas. En nuestro caso esto demuestra un Deshidrogenado incorrecto.
Miguel Angel MartÌn
Q. Dear Martin,
We are extremely interested in your research and your results, please do tell more about it. Thank you
Querido Martin, estamos muy interesados de tu ensayo y de su resultado. GraciasSofia Yen
Research Center - Taiwan
A. Nosotros tambien utilizamos un metodo similar al de Martin pero con dietilenglicol a 160ºC en donde es possible detectar la migracion de burbujas las cuales son de hidrogeno.
Es un ensayo complementario al mencinado en ASTM pero es de ayuda rapida ante alguna duda en elproceso de deshidrogenado
- Buenos Aires, Argentina
Ed. note: We are sorry, but due to the constraints of time this site can no longer do postings except in English. We now receive far more inquiries than we have the time to post and, because of our poor language skills, posting one inquiry in Spanish takes us longer than five inquiries in English :-(
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December 1, 2012
Q. Can we check hydrogen embrittlement by X-ray diffraction method?SHAIKH t.
- Pune, India
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