相变与变形中的约束

Upon phase transformations and plastic deformations involved in material processing and forming, so-called constraints can be defined as physical effects that initiate and develop arising from thermodynamic or thermo-kinetic evolution. Aiming for the formation and deformation of metallic microstructure, the thermodynamic and the thermo-kinetic constraints were herein clarified based on the theoretical framework of material design including thermodynamic stability, generalized stability, thermo-kinetic correlation and thermo-kinetic partition proposed by the current author in recent years. The thermodynamic constraint represented how easy it is for the phase transformation/deformation to be initiated, while the thermo-kinetic constraint was reflected by the nucleation constraint growth and the growth constraint nucleation in terms of the energy change, and by the thermodynamic constraint kinetics and kinetic constraint thermodynamics in terms of progressing transformation. In this paper, representative phase transformations or deformation processes were selected to quantitatively describe the above constraints, and then, an academic concept was proposed to design the constraints artificially and intentionally, to obtain structured materials with excellent mechanical properties through the quantitative design of material processing processes.