Computer Simulation Of Pure Copper During Equal Channel Angular Pressing

As an effective material preparation method for obtaining bulk submicron and nanometer materials,ECAP is attracting a great deal of attention and considered to be the most promising for the preparation of ultra-fine-structured materials.ECAP is a complex plastic forming process under coupled effects of multi-factors with interaction between macro-deformation and micro-structure evolution.Research on macro deformation and microstructure evolution rule has become an important subject urgent to be resolved in the leading field of the ECAP process.Therefore,in this dissertation,a systematic investigation on macro- micro-deformation of ECAP process has been carried out using numerical simulation, A brief introduction to the project and its main achievements are as follows:A model of ECAP process has been developed based on FEM, and some key technologies have been solved, such as materials modeling, element selecting, meshing, contact boundary, fiction, choice of solver and increment step, etc. Based on the platform of software DEF0RM-3D, the microstructure models of copper have successfully been integrated into the macro-FEM model, and consequently simulations of ECAP deformation and microstructure evolution realized.Through comprehensive simulations and analyses of coupled deformation and microstructure evolution of ECAP process, the laws of distribution have been disclosed for deformed process, equivalent strain filed, deformation uniformity, strain rate filed, equivalent stress filed and temperature filed. The influences of main process parameters on equivalent strain filed have been disclosed, including press routes, press passes and die corner.The laws of distribution have been disclosed for dynamic recrystallized volume fraction, dynamic recrystallized grain size, recrystallized volume fraction and average grain size. The effects of press routes and press passes on microstructure evolution have been studied and obtained.In order to confirm the result form computer simulation, comparative analytical and experimental results with simulation results, the results show that the simulation results as same as the analytical and experimental results.