SOLID-SOLUTION HARDENING

Recent advances in the understanding of solid-solution hardening (SSH) of crystalline materials, as well as some basic early papers are brie fly reviewed. This survey shows that models of SSH based on the concep t of a frictional drag on dislocations migrating through fields of poi nt-like obstacles, whether randomly dispersed or clustered, do not enc ompass the principal features of SSH, e.g. the temperature dependence of the yield stress, the stress and temperature dependences of the act ivation volume, and the phenomenon of stress equivalence. However, a m odel based on the nucleation of slip, involving the breakaway of dislo cation segments from several pinning points, formulated in closed form , is shown to account satisfactorily for the principal observations.