The effect of particle reinforcement on the creep behavior of aluminum alloys

The effect of particle reinforcement on the creep behavior of aluminum alloys is reviewed. The direct and indirect strengthening effects of particle reinforcement are examined in pure aluminum, solid solution strengthened aluminum, and age-hardenable aluminum. In pure aluminum, where strengthening is controlled by dislocation substructure, indirect composite strengthening controls creep behavior producing significant reduction in steady state creep rate. In solid solution strengthened aluminum, where a dislocation substructure does not develop, direct strengthening dominates creep behavior giving less strengthening than in pure aluminum. Direct strengthening can be accurately predicted using mathematical models. In age-hardenable alloys, indirect effects can lead to composite weakening at low temperatures, while direct composite strengthening dominates at high temperatures.