Significance of strain reversals in a two-phase alloy processed by high-pressure torsion

▶ The application of cyclic testing in HPT processing were evaluated to a two-phase Zn-22% Al eutectoid alloy under both monotonic (m-HPT) and cyclic (c-HPT) conditions. ▶ All samples showed significant grain refinement after HPT but with a decrease in the hardness by comparison with the initial annealed condition. ▶ There are significant differences in hardness homogeneity between the results obtained in m-HPT and c-HPT. ▶ The data lead to a new and unique variation of hardness with equivalent strain which should apply to other complex alloys where a weakening is introduced due to the high imposed pressure in HPT.