Recent progress in atomic-scale computer simulation in 3 important areas was reviewed. The first was the core structure of dislocations responsible for the primary slip modes, where modeling had revealed the variety of core states that could arise in pure elemental metals and ordered alloys. Whereas most research had successfully used many-body, central-force interatomic potentials, they were inadequate for metals which had an unfilled d-electron band, such as α-Ti, and the resultant non-central character of the atomic bonding was shown to have subtle but significant effects upon dislocation properties. Deformation twinning was an important process in the plasticity of the hexagonal close-packed metals, and modeling was used to investigate the factors that controlled the structure and mobility of twinning dislocations. Furthermore, simulation showed that twinning dislocations were actually generated, in some cases, following the interaction of crystal dislocations with twin boundaries. This could lead to the very mobile boundaries which were observed experimentally. The final area concerned the nature and properties of the defects created by radiation damage. Computer simulation was used to determine the number and arrangement of defects produced in primary, displacement-cascade damage in several hexagonal close-packed metals. The number was similar to that found in cubic metals and was considerably smaller than that expected from earlier models. Many self-interstitial atoms clustered in cascades to form highly glissile dislocation loops and so contributed to 2-dimensional material transport in damage evolution.

Atomic-Scale Modeling of Dislocations and Related Properties in the Hexagonal-Close-Packed Metals. D.J.Bacon, V.Vitek: Metallurgical and Materials Transactions A, 2002, 33[3A], 721-33