Mechanical properties of binary Ni{sub 3}Al single crystals

The mechanical properties of binary Ni{sub 76.6}Al{sub 23.4} single crystalline specimens have been studied in compression test over a wide range of temperature (293--1,100 K). The resolved proof stress ({tau}{sub 0.2%}) and the corresponding work-hardening rate ({theta}{sub 0.2%}) have been measured as a function of temperature. In addition, a technique of repeated stress relaxations has been used to investigate the related microscopic activation volume (V{sub 0.2%}) and to characterize the variation in the density of mobile dislocations that occurs during such transient tests. It is observed that not only {tau}{sub 0.2%} exhibits an anomalous behavior with temperature but also {theta}{sub 0.2%}, while the stress dependence of V{sub 0.2%} may be considered as normal, i.e., V{sub 0.2%} is a monotonic decreasing function of stress.