Abstract: Diffusional hydrogen in the microstructure is thought to be responsible for its embrittlement. Computational modelling can be employed as a means to quantify hydrogen diffusion in steels which, upon reaching a critical concentration, can lead to failure. Microstructural features can also be adopted for hydrogen trapping and delay embrittlement. This seminar will review the theory underlying hydrogen diffusion and trapping in steels, and the conditions for failure. The application of this theory to three applications will be considered: wrought, additively manufactured, and welded stainless steels. Modelling approaches for alloy design and testing strategies will be outlined.

Short bio: Professor Pedro Rivera has been appointed in September 2017 Royal Academy of Engineering Research Chair at Lancaster University.  From 2009 to 2017 he was Assistant Director of Research at the Steel Technology Centre at University of Cambridge, where he taught and led a research group mainly focusing on ultra-high strength steels, but also working on titanium, magnesium, and high entropy alloys. His research has resulted in a variety of novel steel grades leading to three international patents and over 175 articles in international journals (h index = 43). Several modelling approaches have been produced by his group; some of these have been implemented in commercial software. At present, his group at Lancaster University focuses on ‘Alloy and microstructure design for additive layer manufacturing’. From February 2023 he will become Professor in Structural Materials at the University of Southampton.