金属高温塑性成形微观组织演变研究进展

Research overview on microstructure evolution during hot metal-forming

金属在热加工过程中微观组织发生动态、静态回复以及再结晶、晶粒长大等一系列复杂的演化,材料内部微观结构的改变,会直接影响成形后金属的成形质量和力学性能。文章阐述了金属高温塑性成形时微观组织预测模拟的主要研究方法,即直接模拟法、相场法和有限元法;并分别评述了各方法目前在国内外的研究概况、特点以及缺点和适用范围;重点介绍了基于物理本质多尺度耦合的微观组织内变量有限元模型方法。研究结果表明,基于内变量法的微观组织物理模型相对其他方法,最适合用于多尺度微观组织预测数值模拟,模拟结果与实际更为相符,而且最能解释说明各变量演变的物理机制,具有广阔的应用前景。

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.