Numerical studies on processing routes and deformation mechanism of multi-pass equal channel angular pressing processes

Equal channel angular pressing (ECAP) is one of the important methods to produce bulk ultra-fine grain materials. This paper gives three kinds of processing routes for round billet, named as A, B and C, respectively. The processing routes A, B and C are analyzed in detail by using finite element method with node mapping method through rotating three-dimensional model in multi-pass pressing. The distribution of accumulated effective strain and the rules of deformation uniformity of three pressing routes for round workpiece are obtained. The better processing route is acquired through comparing the results of three pressing routes. Influences of different die channel angles on deformation uniformity are studied. The grain refinement mechanisms of equal channel angular multi-pressing for different processing routes are obtained. The obtained results can offer valuable guidelines for ECAP experiments and practical process planning.