Simulation of Multicomponent Precipitation Kinetics using TC-PRISMA

TC-PRISMA is a general computational tool for simulating kinetics of multi-particle precipitation process in multi-component and multi-phase alloys. Developed originally as a stand-alone program, TC-PRISMA has been incorporated into the Thermo-Calc Software suite as the Precipitation Module since 2016. From its first day, it has attracted attention from materials scientists and engineers all over the world and is now widely used by many of them in both academia and industry. Just like Thermo-Calc and DICTRA, the success of TC-PRISMA relies on the solid CALPHAD foundation that has been built over decades where the Gibbs energy and atomic mobility as well as thermophysical properties of each phase can be modeled hierarchically from unary to binary and then to ternary so that CALPHAD databases can be constructed for quickly obtaining multicomponent data, which is otherwise difficult or impossible to find, on phase equilibria, driving forces, diffusivities, molar volume, interfacial energy, and so on, that are essential for quantitatively simulating microstructure evolution in industry alloys.

Precipitates as dispersed second phase particles embedded in a solution phase matrix provide many alloys with their desired strength and toughness. A precipitation microstructure is mostly a product of diffusion-controlled solid state phase transformation that is fully governed by system (bulk and interface) thermodynamics and kinetics. With the advance of CALPHAD tools and widely available databases, computer simulation of the precipitate microstructure in multicomponent alloys is feasible on the basis of the Langer-Schwartz theory and Kampmann-Wagner numerical (KWN) method. In this webinar, our efforts in developing TC-PRISMA for treating concurrent nucleation, growth, and coarsening of second phase particles in multicomponent systems will be presented. Nucleation and growth rate models implemented in the software will be elaborated on. Examples of precipitation modeling in different alloys will be shown and discussed to demonstrate its capability and user-friendliness.