GLOBAL VIEW OF MICROSTRUCTURAL EVOLUTION:ENERGETICS,KINETICS AND DYNAMICAL SYSTEMS

<正> An evolving material structure is in a non-equilibrium state,with freeenergy expressed by the generalized coordinates.A global approach leads to robustcomputations for the generalized thermodynamic forces.Those forces drive variouskinetic processes,causing dissipation at spots,along curves,surfaces and interfaces,and within volumetric regions.The actual evolution path,and therefore the finalequilibrium state,is determined by the energetics and kinetics.A virtual work prin-ciple links the free energy landscape and the kinetic processes,and assigns a viscousenvironment to every point on the landscape.The approach leads to a dynamicalsystem that governs the evolution of generalized coordinates.The microstructuralevolution is globally characterized by a basin map in the coordinate space;and bya diversity map and a variety map in the parameter space.The control of basinboundaries raises the issue of energetic and kinetic bifurcations.The variation ofbasin boundaries under different sets of controlling parameters provides an analyticalway to plot the diversity maps of structural evolution.