A quantitative model was proposed for the peak temperature in the work-hardening of L12 intermetallics. It was based upon a competition between the exhaustion of mobile dislocations via the Kear-Wilsdorf mechanism, and the yielding of incomplete locks at high stresses. The model was compared with experimental data on binary Ni3Al polycrystals of 3 different compositions. These included the planar fault energies of the dislocation cores, as measured by weak-beam electron microscopy combined with computer-image simulation, and macroscopic data on flow stress, work-hardening and mobile dislocation exhaustion rates. The parameters were measured as a function of alloy composition. The model also successfully fitted data on 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