OBITUARY : Professor Peter Pratt

Peter Pratt was one of a small group of British scientists who brought about the evolution of materials science as an academic discipline from metallurgy. The subject now plays a critical role in manufacturing industry, determining the development of new materials for structural and functional applications and providing the scientific understanding of the properties which they exhibit.

Pratt began his career at Birmingham University, where he graduated with a First Class degree in metallurgy. As a postgraduate he had the good fortune to work, in the Cavendish Laboratory at Cambridge, under the direction of Sir Lawrence Bragg and Professor Erwin Orowan, two towering figures in the study of the microstructure and properties of materials. His research culminated in a PhD on plasticity in sodium chloride - itself a notable contribution to this subject. He also became acquainted with metal fracture in a direct way while participating, as a member of a Cambridge team, in the Isle of Man TT motorcycle races.

Following a period at the Harwell Laboratory, in Oxfordshire, Pratt returned to Birmingham and a lectureship in the Metallurgy Department, working under Professor (now Sir) Alan Cottrell with other notable materials scientists including Frank Nabarro and Robert Cahn. His work there on dislocations and the mechanical behaviour of ionic crystals extended considerably our understanding of this class of material. In 1959 he was appointed to a readership in the Department of Metallurgy (now Materials) at Imperial College, London, and in a very short time was promoted to the Chair of Crystal Physics at the young age of 36, a position he occupied until his retirement three years ago.

Pratt never followed the fashionable research topics of the day but always chose to work where he saw the need for scientific understanding of materials. He led the way in the study of relationships between the structure and properties (with emphasis on brittle fracture) of materials ranging from ionic compounds, hexagonal and body-centred cubic metals and technical ceramics to cements and concretes. It was at a stage in his career when many would have been content with past achievement that Pratt launched himself into the complex world of cement and concrete chemistry, the setting reactions and consequent microstructural development which determines the mechanical behaviour of this essential constructional material. The cement research group grew rapidly, and resulted in frequent invitations to international meetings and long-term links with prominent US cement research laboratories. When trips took him to New England he was also able to enjoy sailing, a lifelong hobby.

Pratt brought to all his research great enthusiasm and intellectual rigour, which inspired the many research students he supervised. He had a gift for attracting the most talented, to whom he gave considerable freedom in exploring their research topic, intervening only occasionally, and with great acuity. Many of his former students have achieved prominence in academia and industry.

But it was not only his students who benefited. He displayed consideration for all with whom he worked, technical, secretarial and academic colleagues alike. He took an active role in departmental and college activities and could be a formidable adversary in debate. He put the same degree of devotion into college business as he did into his research and gave freely of his talents as Dean of the Royal School of Mines, member of the Governing Body, Director of Continuing Education and of the London Centre for Marine Technology.

Pratt's research experience taught him the essential unity of the science of all engineering materials and the need for this to be expressed in teaching. Metallurgy had long been an academic subject and concerned with the understanding of the relationships between structure and properties of metals, but this approach needed to be extended to all engineering materials to meet the needs of the latter part of the 20th century and beyond. During the 1960s he, with colleagues from several departments in Imperial College, set about creating a materials science course, since developed into the Materials Science and Engineering undergraduate course. The integration of the study of materials has gathered unstoppable momentum since then and has culminated in Britain in the amalgamation of the professorial societies concerned with materials into the Institute of Materials. Among Pratt's numerous honours and awards are the Beilby Medal (in 1964) and the Griffiths Medal (1990) of the institute.

Peter Pratt's teaching and research gave him a deep insight into the way in which the development of materials influences the way society operates and he applied this to a range of historical subjects, including the medieval and Tudor "arms race" which took place as improvements in the materials for armour were balanced by the increasing penetrating power of the arrow, and culminated in his studies, with the actor Robert Hardy, of the longbows recovered from Henry VIII's flagship the Mary Rose. A laboratory in the Royal School of Mines was converted, temporarily, into an archery range as he and Hardy carried out the essential experimental studies of the penetrating power of arrows fired from the remarkably well- preserved bows.

The rigorous analysis of the mechanics involved has contributed substantially to our understanding of English firepower of the day and was conveyed to a general audience in a book, Longbow (1976, with a new chapter on the Mary Rose longbows added in 1992), written jointly with Robert Hardy, and in lectures on the subject which were characterised by humour as well as learning.

Harvey Flower

Peter Lynn Pratt, materials scientist: born 10 March 1927; Research Fellow, Atomic Energy Research Establishment, Harwell 1951-53; Lecturer, Birmingham University 1953-58; Reader in Physical Metallurgy, Imperial College 1959-63; Professor of Crystal Physics, Imperial College, London 1963-92 (Emeritus), Dean, Royal School of Mines 1977-80, Member, Governing Body 1977-80, Director of Continuing Education 1981-86; married 1951 Lydia Hatton (two sons); died Beaconsfield 2 March 1995.