Abstract
The mechanical properties and microstructure of AM60 Magnesium alloy processed by a new cyclic extrusion channel angular pressing (CECAP) technique were investigated in this research. In this novel method, a low extrusion ratio stage was added at the end of the CECAP process to enhance the hydrostatic stresses and equivalent strain. The structure was refined from the average grain size of ~ 76 µm for the annealed samples to 2.63 µm in the new CECAP after four passes. While for the CECAP and ECAP processes, it was 3.43 and 6.98 µm, respectively. Experimental results of the proposed CECAP process showed an improvement in the mechanical properties after the second pass that were stopped for the ECAP process. However, the hardness of the CECAP-processed and proposed samples was constantly increasing. This increase in hardness was 196% and 175% for the proposed CECAP and CECAP processes after four passes compared to the unprocessed sample, respectively. Moreover, the compressive yield stress and ultimate compressive strength of the CECAP-processed samples were higher in all passes; however, they were smaller than those of the proposed CECAP process. The hydrostatic compressive stresses and higher plastic strain in the proposed technique helped in further refining of the grains, which can effectively improve the mechanical properties