Frank Nabarro is remembered as one of the great pioneers who developed the theory of dislocations in solids and thereby strikingly advanced understanding of the mechanical behaviour of metals. In two crucial areas he addressed the problem of the stress required to initiate plastic flow: first in metals alloyed to produce precipitates (precipitation hardening), and second in pure crystals of all types in which dislocation movement is impeded only by the intrinsic lattice resistance (Peierls–Nabarro stress). He predicted the slow creep of crystals at high temperature by the movement of single vacancies (Nabarro–Herring creep), a universal phenomenon of great engineering importance. Working from the University of Witwatersrand he edited Dislocations in solids, a series of review articles that continue to be essential keys to the huge unruly literature on dislocations. In South Africa he had an important role not only in developing solid state physics but also in promoting educational opportunities for students of all races, particularly in planning university expansion to accommodate the much larger student numbers expected after the end of apartheid, a policy that he vehemently opposed.
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