Simultaneous calculation of mechanical properties and phase equilibria

Many formulas have been developed to describe the mechanical properties of various microstructures, but there have been relatively few attempts to com bine such formulations directly with multicomponent phase diagram calculati ons obtained by the CALPHAD technique. This paper describes some of the tec hniques used in developing such a combined approach as part of a more compr ehensive materials property program (MPP), The basic requirement is to desc ribe the mechanical properties of the overall alloy by determining the effe ct of each solute, and the grain size, on the mechanical properties of the various phases in a multicomponent system. As some of the coefficients are not readily available, methods have to be evolved that echo problems alread y faced by the CALPHAD community with respect to characterizing the thermod ynamics of metastable phases. It will be shown how the inter-relation of va rious mechanical properties, such as yield strength and hardness, can also be used to produce self-consistent data. The promising results obtained for dual-phase materials can be considered a firm Foundation for future work o n more complex systems.