The radiation-induced amorphization of these materials was simulated by using molecular dynamics methods and embedded-atom potentials. Changes in the system energy, volume, pair-correlation functions, atom projection, and elastic constants were analyzed. It was found that amorphization occurred in 2 steps. The first one was the introduction of chemical disorder via point defect recombination, and the second was the stabilization and accumulation of point defects; leading to lattice instability. The build-up of point defects was a necessary factor in the amorphization of these materials. The calculated damage doses which were required to render the compounds completely amorphous were equal to about 1dpa for CuTi and to 0.6dpa for Cu4Ti3. The resultant volume expansions (about 1.9 and 1.7%, respectively) were in general agreement with experimental observations. At the onset of amorphization, the average shear modulus decreased by a factor of about 2; in good agreement with experiment.

N.Q.Lam, M.J.Sabochick, P.R.Okamoto: Radiation Effects and Defects in Solids, 1994, 129[1-2], 91-8