Hydrogen concentration test methods 2

[CoryPad]

What are the preferred methods to measure hydrogen concentration in metallic solids? I am aware of ASTM methods, but would like opinions.

What methods show correlation with Hydrogen Induced Cracking in high-strength steels? I have been told (with no documentation/proof) that the combustometric measurement method using a Leco detector does not correlate with failures.

 

[mcguire]

Corypad
I did research on hydrogen embrittlement and never came across any claim that the degree of embrittlement could be correlated to measured hydrogen content. That is probably because the mechanism of embrittlement is mobile hydrogen moving to points of tri-axial stress, so it is a very localized concentration that counts.

 

[yates]

Corypad,
I would agree with mcguire. Several ASTM methods are called up for the required (one per batch) measurement of H2 content in finished aerospace bolts in Ti6Al4V.I have never come across any correlation with tendency to induce cracking. I believe that a very local concentration of hydrogen could have disastrous effects upon tendency to crack, whereas most methods of analysis require a relatively large volume (approx.0.008 in3) and therefore give an average content.
yates