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This work examined the effects of Li content on the strain-hardening behaviors of three varieties of Mg−Li−Zn alloys containing approximately 6 wt%, 9 wt%, and 10 wt% of Li. Tensile tests were carried out on specimens in the directions of 0, 45 and 90° to the rolling direction. Kocks–Mecking type plots were constructed to illustrate different stages of strain-hardening. The cold-rolled Mg−6Li−1Zn (designated as LZ61) alloy sheet showed stage II and stage III strain-hardening behaviors at room temperature. The specimens of Mg−9Li−1Zn (designated as LZ91) and Mg−10Li−1Zn (designated as LZ101) alloy sheets did not show stage II strain-hardening. Higher initial strain-hardening rates were observed in the 90° direction for these alloys as a result of the cold-rolled fibrous structure affording stronger barriers to dislocation movements in this direction.

The flow behavior and associated structural changes of an AZ61 Mg alloy were analyzed by using hot compression tests in the temperature and strain rate ranges of 250–400 °C and 0.001 to 1 s–1, respectively. The stress–strain curves exhibited the trend typical of materials in which deformation is recovery-controlled in the high Z regime (Z is the Zener–Hollomon parameter), while at low strain rates and high T, the flow curves exhibited a softening typical of recrystallization phenomena. Microstructure analysis has been performed to correlate the microstructure changes to the flow behaviors.

The flow behavior and associated structural changes of an Inconel 600 superalloy were analyzed by using hot compression tests in the temperature and strain rate ranges of 850–1200 °C and 0.001 to 10 s–1, respectively. The stress–strain curves exhibited the trend typical of materials in which deformation is recovery-controlled at high strain rates and low temperatures, while at low strain rates and high temperatures, the flow curves exhibited a softening typical of recrystallization phenomena. Constitutive analysis was carried out to investigate the hot deformation mechanism using the hyperbolic sine law.