Mike Sellars FREng FIMMM 1935-2012
Christopher Michael (Mike) Sellars made outstanding contributions in research and in teaching metallurgy. He entered the University of Sheffield as an undergraduate in 1953, later becoming a member of staff and, excepting temporary appointments overseas, he continued to serve the University well beyond his formal retirement in 2001.
After attending Rotherham Grammar School and Ackworth School, Mike’s ability was recognised at university by a Ledingham Bursary, which supported his path to a first class honours degree. Research on the creep of solid solutions followed, resulting in a PhD and University Brunton Medal in 1959. A Fulbright Scholarship next led to three years as Metallurgical Research Engineer at Carnegie Institute of Technology, Pittsburgh, before returning to Sheffield as University Lecturer in Metallurgy in 1963.
Mike’s research centred on microstructural changes and improvements in properties that could result from hot working. Following W J McG Tegart’s departure in 1967, Mike became leader of this research area and long continued to focus on it. Experimental methods expanded from early use of torsion bar specimens to increasingly sophisticated techniques involving servo-hydraulic machines with computer control and rapid data recording, operating at high temperatures on specimens with geometrical changes measured up to large strains. A proliferation of results ensued, first to proposals of useful empirical formulae representative of dynamically steady conditions, and on to the interpretation of microstructural and property changes under more complex procedures in simulation of industrial processes. These included influences of hot working rates and pressures, variable temperatures, surface effects, friction and stress distribution, multi-passes and stress-free dwell times. These parameters were linked with phase transformations, precipitation kinetics, particle coarsening, grain boundary mobility and pinning, and with crystal defect behaviour. Advances in modelling methods provided appropriate tools for translation to commercial manufacturing of a wide range of alloys, demonstrating the benefits of a broad approach. This came from close collaboration between Metallurgy and the University Departments of Mechanical and of Automatic Control and Systems Engineering, and led to the founding of IMMPETUS (Institute for Microstructural and Mechanical Process Engineering at the University of Sheffield). Mike remained active within this, latterly as a part-time Senior Research Fellow.
The value of the research was widely recognised and Mike received honours, including: Honorary Degree of C Mech D from University of Navarro, Spain – Charles Hatchett Award, Thomas Medal and Prize, and Williams Prize from the Institute of Materials, Minerals and Mining – Honourable Medal of the Faculty of Metallurgy and Materials Engineering from the University of Krakow, Poland – Honorary Membership of the Materials Research Society of India – Honorary Membership of the Indian Institute of Metals – Fellowship of the National Academy of Engineering, India – Fellowship of the Royal Academy of Engineering, UK and finally the IOM3 Bessemer Gold Medal in 2010.
Mike’s teaching to undergraduates and postgraduates was not reduced by his high level of research, nor was his participation in wider university administration. He remained a dedicated, thorough and highly respected lecturer. Students appreciated laboratory demonstrations and the ease of taking notes, and valued his jointly authored textbooks on quantitative metallography and on worked examples in metalworking. Promotions ensued, including to a Personal Chair in Metallurgy in 1983. Five years later, he was appointed to the new POSCO Chair of Iron and Steel Technology. From 1991–1995, Mike served as Head of the newly named Department of Engineering Materials and played a large part in its formation from the former separate Departments of Metallurgy and of Ceramics, Glasses and Polymers. Then followed a period, from 1996–1999, as Dean of the Faculty of Engineering.
Mike’s work was characterised by energy, care and persistence. Underlying his large frame, he was sensitive and invariably approachable to students and colleagues at all levels. He gave valued advice and help to many people, who remain grateful. Visitors to the University frequently recall the warmth of his reception and the time he was willing to spend with them. Away from work, Mike’s activities were firmly rooted in his home life. He and his wife Mavis enjoyed many activities, including dancing, theatre, golf and supporting local societies and events. During the 52 years of their marriage they travelled widely to many parts of the world. They took pride in the activities of their three children and their grandchildren, with whom they were always delighted to be involved. Mike will be much missed, professionally and personally, but his wide contributions remain.