Some recollections of the radiation damage work of the 1950s

Abstract

The wartime nuclear energy efforts in the United States had led to considerable work on the problems associated with the displacement of atoms in crystals by particle irradiation. Naturally at first the interest was concentrated on the changes induced by neutrons or fission fragments. The group at the Atomic Energy Research Department of North American Aviation, Inc., at Downey, California (M. M. Mills, W. E. Parkins, A. Yockey) was the first to appreciate the advantages of radiation damage studies by means of charged-particle irradiation. M. M. Mills (who unfortunately was killed in an aeroplane accident not long afterwards) recognized the important fact that electrons coming from the usual electron accelerators have just the right energy to transfer to atoms in metals kinetic energies comparable with or somewhat larger than the threshold energies required for creating permanent displacements. Thus the use of charged-particle irradiation, and in particular of electron irradiation, which still dominates the field of radiation damage in metals, had its origin in the Atomic Energy Research Department of North American Aviation. It has been continued until the present at Atomics International.