Simulation Of Dynamic Recrystallization Based On Monte Carlo Method

Dynamic recrystallization is one of the most important physical metallurgical processes during the metal hot deformation. Researching the law of dynamic recrystallization, predicting and controlling the evolvement of microstructure, have important significance for determining the best technology parameters and optimizing the production performance. Through the long-term research on recrystallization, scholars have got a lot of research achievements, such as dislocation theory, phenomenological theory and so on. But, as the result of the limits of detecting methods and deformation conditions, the explanation of microstructure evolvement have a lot of deficiencies.Recently, in order to reflect the recrystallization kinetics and topology synthetically and directly, many international and domestic researchers have established series of models of recrystallization and grain growth based on the Monte Carlo method (MC) and Cellular Automate method (CA). They combined the graphical technology and simulation theory, presented the process of microstructure evolvement lively by graphics mode, and broke a new path for the research of recrystallization theory. But, in the field of dynamic recrystallization, the research was still on the inchoative stage, and the published models had some deficiency. Consequently, besed on hot simulation test and relational theories, a model which has better physical and experimental foundation was established and its relational programs were compiled by MC method for simulating dynamic recrystallization in this paper. And the processes of microstructure evolvement during dynamic recrystallization of o9CuPTiRe steel were researched.Firstly, by integrating the thermal simulation test, deforming mechanism, nonlinear regression method and MC method, a new method was proposed to establish and optimize the constructive model of material, which was of completely and continuously dynamic recrystallization.Secondly, on the one hand, by combining the constructive equation, a new energy model that put the energy on the nodes was established, and based on the size of deforming grain, a model that depicted the distribution of energy was proposed. On the other hand, based on the recrystallization theory and deforming characteristics, models of nucleation and growth were established respectively, which fitted the process of dynamic recrystallization well.Thirdly, based on the models that had been established, simulation programs were compiled by using Visual Fortran. Then the programs were applied successfully to simulate the process of dynamic recrystallization, the results which included microstructure evolving images, energy varying characteristics, average size varying characteristics, and volume percentage of dynamic recrystallization, accorded with the actual physical process, and the dynamic recrystallization kinetics accorded with the Avrami equation very well.Finally, the paper completed the simulation under different deforming velocity and deforming temperature. The results showed that the quicker the deforming velocity, and the lower the deforming temperature, the more difficultly the dynamic recrystallization took place, and the rule of variation accorded with the relational theory and experimental results very well.