Overall activation energy of isothermal transformation in metal alloy and its mechanism II. Isothermal transformation in β brasses

Similarly to steels, in the isothermally treated β brasses, the plate-like α₁(bainite) and rod-like α have all themselves C curves. A single phase is always produced in the primary stage, whereas the nearby two-phase complex is usually produced in the medium or final stage of the transformation. Only a single phase and Arrhenius equation must be used to deduce the overall activation energy for the transformation product. By a combination of overall activation energy, morphology and change of free energy, it can be explained that the plate-like α₁(bainite) transformation mechanism follows military atom diffusionless martensite-like shear, occurring in solute-depleted region controlled by solute atom diffusion in parent phase β′, and the rod-like α phase results from civilian atom diffusionless interphase control transformation, occurring in the most solute-depleted region controlled by solute atom diffusion in parent phase β′.