Tailoring the textures and mechanical properties of AZ31 alloy sheets using asymmetric composite extrusion

In the present study, an effective asymmetric composite extrusion (ACE) was used to produce AZ31 magnesium alloy sheets and compared with the composite extrusion (CE). The microstructures, textures and mechanical properties of AZ31 magnesium alloy sheets processed by CE and ACE processing at room temperature were investigated. The results demonstrated that the grains of the sheet fabricated by ACE processing were refined and the anisotropy could be improved in the tensile direction of ED, 45° and TD compared with the sheet fabricated by CE processing. The yield strength of the sheet processed by ACE was lower than that of the sheet processed by CE with the decrease of about 35 MPa in the TD tensile direction, and its ductility was increased from 26.1% to 31.4% in the 45° tensile direction at room temperature. The higher n-values and lower r-values were obtained for the sheet processed by ACE processing in three tensile directions. These results led to a good formability of the sheet fabricated by ACE at room temperature. The improved mechanical properties of AZ31 Mg alloy sheet were mainly attributed to texture weakening resulting from asymmetric shear strain during ACE processing.