Hydrogen embrittlement of complex microstructures in steels

A lecture given at Manchester University International Centre for Advanced Materials on hydrogen in complex mixtures of phases within steels.
There are aspects of hydrogen in steels that are crystal clear. For example, that hydrogen in solid solution embrittles, does not require further work. The mechanism by which it embrittles is far from clear, and there is no generic theory capable of rationalising the vast quantities of data available in the published literature. When combined with the fact that practical alloys have complex mixtures of phases and defects, the confusion can be said to be complete.
However, all is not lost because measures can in principle be taken to limit the potency of hydrogen. The talk begins with an introductory review of the subject, mention specific examples where significant performance enhancements have been observed, and deal with the theory and new experimental data on the passage of hydrogen through complicated mixtures of phases.
www.phase-trans/msm.cam.ac.uk/2014/hydrogen.html

[@kelvinxie1029]

Amazing lecture given by Professor Bhadeshia. I learned so much about hydrogen embrittlement from this talk.

[@bhadeshia123]

Glad you enjoyed it.

[@KarthikIyerCoep]

Thank you Professor for sharing such an informative and insightful lecture

[@bhadeshia123]

You are welcome.

[@rhwheeler]

Thank you for your insight into this subject. I particularly liked the electron microscope images and description of Hydrogen diffusion with supporting graphs. I understand that it is costing £1m to replace bolts at the "Cheesegrater" and needed to brush up on the topic.

[@bhadeshia123]

Thank you, you are most welcome.

[@dr.-inghuh797]

Very interesting lecture Prof. Bhadeshia.

[@bhadeshia123]

Thank you.

[@modernwest100]

Can I use HHO to melt steel in a crucible without damage to steel and make a proper pour in a mold? Thanks

[@ericamorim3886]

Thank you Professor!

[@bhadeshia123]

You are welcome

[@rhwheeler]

Leadenhall Building aka the Cheesegrater update - At a cost estimated at £6m, 3000 bolts are now being replaced "as all parties agree it is sensible". No source for the Hydrogen diffusion has been determined.

[@bhadeshia123]

Richard Wheeler Thank you for that - I looked up the stories after your message. There are sparse technical details in the web reports, so my comments that follow are not necessarily applicable or relevant. Static, delayed failure in strong bolts is a known problem with high strength steel bolts and steels are available that contain appropriate hydrogen traps and hence mitigate such events. See for example, the Nippon Steel Technical Report 101, November 2012, (NSTR101-23_tech_review-3-4.pdf) available freely on the web.