Solute-vacancy interaction energies in the α-phase were investigated systematically by performing super-cell total-energy calculations, using linear muffin-tin orbital methods, within the atomic sphere approximation. The solutes which were studied included most of the elements from the third to the fifth row of the periodic table. The results showed that most of the transition-metal elements in the fourth row were repulsive to vacancies. The simple metals, and all of the transition-metal elements in the fifth row, were attractive to vacancies. The interaction energy between the transition-metal solutes and vacancies in the α-phase did not exhibit the parabolic behaviour, predicted by the d-band filling mode, which had been used to explain trends in interaction energy in Cu and Ag. It was considered that this deviation was related to the structural instability of some of the solutes in the hexagonal close-packed lattice. On the basis of the solute-vacancy interaction energy, a simple relationship was found between solute-vacancy interaction and high-temperature creep properties. That is, those solutes which attracted vacancies could improve the creep resistance, while those which repulsed vacancies had no beneficial effect upon creep resistance.

First-Principles Investigations of the Solute-Vacancy Interaction Energy and its Effect on the Creep Properties of α-Titanium. Q.M.Hu, D.S.Xu: Philosophical Magazine A, 2001, 81[12], 2809-21