A quantitative model for the peak temperature in work-hardening in L12 intermetallics was proposed. It was based on the competition between the exhaustion of mobile dislocations by the Kear-Wilsdorf mechanism and the yielding of incomplete locks at high stress. The model was assessed by a set of experimental data measured in binary Ni3Al polycrystals of three different compositions. These include, in particular, the planar fault energies of the dislocation cores measured by weak-beam electron microscopy, combined with computer image simulations and macroscopic data about flow stress, work-hardening and mobile dislocation exhaustion rates. These parameters were measured as a function of alloy composition. The model also fits successfully data published for other L12 compounds.

From Dislocation Cores to Strength and Work-Hardening: a Study of Binary Ni3Al. Kruml, T., Conforto, E., Lo Piccolo, B., Caillard, D., Martin, J.L.: Acta Materialia, 2002, 50[20], 5091-101