LONDON MATERIALS SOCIETY  42nd AGM and Liddiard Memorial Lecture  Thursday 8th May 2008 For AGM notice and agenda please click here. AGM starts at 18.30hrs at 1 Carlton House Tce, SW1Y 5BD Liddiard Memorial Lecture Reactive Steels: the making of calm welds Prof Harry Bhadeshia, Cambridge University Lecture starts after the AGM Lecture is free to attend and open to all. Venue: Inst. of Materials, Minerals and Mining, 1 Carlton House Tce, London, SW1Y 5DB Abstract ======== Steels are at their best when they can be joined in order to fabricate the structures that we take for granted in everyday life. Indeed, life without these joints is unthinkable, and an average family owns some 5000-10000 welds. Whilst there are ingenious methods of welding steels, the liquid produced must inevitable contract on solidification. This combined with the localised nature of the weld results in the accumulation of stress even before the structure has been externally loaded. In this lecture I will demonstrate a possible method in which steel welding alloys are designed to react to the accumulated stress, cancel it, and place the joint in a desirable compressive state. And to add to the mystery, we exploit here a phase which is normally regarded to be brittle. This naturally must be done whilst maintaining other properties; attempts to do this have led to the discovery of a new phase in steels which I shall describe. Biography ========= Harry Bhadeshia is arguably the UK’s leading academic researcher in ferrous metallurgy, specialising in the solid-state transformations. He has made a name for himself in connection with the bainite reaction in particular and its subsequent microstructure and properties, and the development of new novel alloys. He has written two definitive and groundbreaking books on this subject. However, his research is not restricted to steels, as he has also made invaluable contributions to the understanding and development of nickel based alloys for aerospace and power generation applications. He has developed advanced modelling techniques, extensively backed up by rigorous experimental techniques and validations, and has published over 350 papers and books. Prof. Bhadeshia enjoys excellent working relationships with UK manufacturing and engineering industries and is passionate about improving public understanding of science and industry.