A numerical modelling and investigations of flow stress and grain refinement during equal-channel angular pressing

Equal-channel angular (ECA) pressing is one of the most widely used techniques of severe plastic deformation (SPD), applied to obtain bulk nanostructured samples and ingots. The last ones are of great interest due to their extremely attractive enhanced physical and mechanical properties. However, such properties are intrinsic only to certain ultra fine-grained nanostructured states, characterized with high angle grain boundaries. It is rather difficult to form such nanostructured states due to the numerous varying parameters of ECA pressing technology (strain, strain rate, temperature, etc.) and peculiarities of straining material. The results of the modelling experimental and computer investigations are cited in the present paper. They are aimed at analysis of plastic flow and the strained condition of bulk SPD ingots and further recommendations on conducting the ECA pressing process and as a result developing of optimal nanostructured states in bulk ingots of different metals including hard-to-deform ones. Example material is Cu (99.9%).