Research overview on microstructure evolution during hot metal-forming

A series of complex microstructure evolutions, such as dynamic and static recovery and recrystallization, grain growth etc., take place during hot metal-forming.The microstructure changes directly influence the forming quality and mechanical properties of products.In order to improve the quality of products and save research expenditure, microstructure evolution numerical simulation technology is more and more popular.This review states the several major research methods of microstructure prediction simulation, such as direct simulation method, the phase field method and finite element method.And all these methods, including their characteristics, range of applications and shortcomings, are reviewed respectively in the domestic and international metal forming research field.Especially this review focuses on the finite element multi-scale coupling numerical simulation model based on physically-based internal state variable method.Research results show that the microstructure prediction physical model based on internal state variable method best fits the multi-scale numerical simulation.The simulated results match the reality to the best and can also explain the physical mechanism of the evolution of variables.Therefore, it has great potential for application.