Abstract：Equal channel angular pressing (ECAP) is an interesting method for changing microstructure and producing ultra fine grained (UFG) materials through super-plastic deformation. The homogeneous deformation is the main factor that influences the material performance during ECAP. Four processing routes are analyzed in detail by using finite element method with spatial switching method through rotating three-dimensional model in multi-pass pressing. The accumulated effective strain distribution of the work-piece processed by ECAP for four pressing routes are obtained respectively through finite element simulation. The processing route that can generate more homogeneous effective's main distribution in sample after four routes processing is defined. The mechanical property of AZ31 magnesium alloy processed by multi ECAP passes in different routes was analyzed through microstructure observation and mechanical tensile test at room temperature. The experimental results show that the fine and uniform microstructure can be acquired by appropriate deformation route, the mechanical property of AZ31 magnesium alloy is greatly improved when strain accumulation uniform after ECAP processing.
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