EFFECT OF NONISOTHERMAL HEATING OR COOLING ON GRAIN-GROWTH

A critical area in nanocrystalline materials research is development o f grain growth relations for controlled, uniform heating or cooling. T heoretical relations describing nonisothermal coarsening are derived i n terms of classical isothermal materials properties. An effective tem perature is defined as the temperature at which equivalent coarsening occurs to that predicted during the heating or cooling period. This pa rameter is only a function of the endpoint temperatures and the activa tion energy for grain growth. Simplifications of the equations for gra in size and effective temperature are derived and their implications d iscussed.