| Citation | Distinguished for his researches on the structures and properties of alloys. He pioneered the application of high resolution electron microscopy to the study of the fine structures formed in the decomposition of supersaturated solid solutions in aluminium and other alloys. He demonstrated the existence of elastic strains round microscopic particles of precipitate, coherent with the matrix crystal, and his work on the crystallographic and elastic factors which determine the symbiotic association of precipitates and dislocations is especially beautiful. He also laid down the basis for understanding the catastrophic deterioration of certain strong industrial alloys due to localised precipitation at grain boundaries. Other fields in which he has made important contributions include the nickel-base gas-turbine alloys, and superplastic alloys. |