In
World War II Eshelby began working for the
Admiralty on the degaussing of ships, but on 4 May 1940 he joined the Technical Branch of the
Royal Air Force. His work from February 1941 to June 1942 was for the
Coastal Command Development Unit conducting performance trials of
air-to-surface-vessel radar and other operational devices in all types of aircraft. He was then involved in radar work, from August 1942 to February 1943 with 76 signals wing and from February 1943 to September 1944 at the radar establishment at Malvern. He was then transferred to disarmament work and then to the Air Historical branch in September 1945. He left the RAF as a squadron leader on 4 October 1946. where he taught from 1953 to 1964 at the Department of Metallurgy. During this time, he worked on point defects and dislocations, developing the method of 'transformation strains' and studying the Eshelby inclusion problems for the first time, as well as the study of forces on elastic singularities. In 1964 he moved to the
Cavendish Laboratory at
Cambridge University at the behest of Neville Mott, and was a Fellow of
Churchill College from 1965 to 1966. He was then appointed Reader in the Faculty of Materials (Theory of Materials) at the
University of Sheffield, where he became Professor in 1971. == Personal life and death ==