Obituary - Donald McLean DSc FIMMM

Fellows' Lounge
1 May 2018

Donald McLean DSc FIMMM 1915 - 2017

This is a tribute for the life of the extraordinary centenarian Donald McLean DSc FIMMM, a truly legendary physical metallurgist of the 20th century whose great first book, Grain Boundaries in Metals, published by Oxford University Press in 1957, had an enduring influence on a whole generation of physical metallurgists.

Donald Mclean was a leading figure at the National Physical Laboratories (NPL) of the UK for over thirty years, following the traditions of the Australian Walter Rosenhain (1875-1934), who had established NPL as a leading world laboratory developing his amorphous cement theory of grain boundaries in creep and creep facture.

McLean had a remarkable career as a researcher and a particularly beneficial influence on many of his young proteges at NPL including Brian Dyson, Martin Seah, Malcolm McLean, Ernie Hondros, and, more widely, in the national and international community in his discipline, pioneering the application of the quantitative analysis of micro-mechanisms to engineering design and life assessment, especially in high temperature creep.

A second major book, The Mechanical Properties of Metals, reflected his contributions to the role of defects in materials design. McLean was one of the first to address the role of dislocations in the structural integrity of materials, and he pioneered the application of thin film high voltage electron microscopy to understand their micro-mechanisms and thereby contribute substantially to materials design.

McLean later focused on the quantitative aspects of fracture and developed a methodology called predictive metallurgy. This enabled the prediction of materials behaviour using rules governing the underlying physical processes leading to reduced dependence on empiricism. His ICF4 Plenary Paper in 1977 established the framework for thirty years of further work on creep damage mechanics and this contributed to the engineering and manufacturing development of single crystal nickel-base superalloy turbine blades for Rolls-Royce engines and models for the life prediction of various industrial components.

Donald McLean was one of the greats of physical metallurgy and structural integrity alongside such as Griffiths, Irwin, Rosenhain, Mott, Hume-Rothery, Orowan, Cottrell, Ashby, McClintoch and an influential contributor to IOM3 and the earlier Institute of Metals for many years. His name will be forever remembered in the annals of physical metallurgy among those leading the transformation of the discipline from a qualitative metallurgical art to a quantitative materials science.

Professor D M R Taplin FIMMM