Sir Alan Cottrell FREng. 17 July 1919 — 15 February 2012

Sir Alan Cottrell was a man who achieved the highest possible distinction in a number of roles relating to science and education. He is rightly regarded as the outstanding physical metallurgist of the twentieth century. His career began at the University of Birmingham, where, first as lecturer, then as professor, he made two major contributions. The first was to relate the properties of metals and alloy systems to their electronic structures and to thermodynamical factors; the second was to relate the mechanical properties of solids to the defects that they contained: point defects such as vacancies and interstitials, and line defects such as dislocations. His work in both these topics proved to be instructional and inspirational for generations to come. He next spent a period at Harwell, making major contributions to the UK’s nuclear reactor programme. He then moved to Cambridge to regenerate a somewhat moribund Department of Metallurgy. His success was such that, through the lines of research that he created and the people that he brought in, the Cambridge Department is now recognized as a world leader. His own research made great advances in the treatment of the brittle fracture of steel.