Improved mechanical properties of Mg-3Al-1Zn alloy sheets with TD-preferred texture prepared via turned bearing extrusion
(1. National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044, China;
2. Chongqing Academy of Science and Technology, Chongqing 401123, China;
3. School of Mechanical Engineering, Yangzhou University, Yangzhou 225127, China)
2. Chongqing Academy of Science and Technology, Chongqing 401123, China;
3. School of Mechanical Engineering, Yangzhou University, Yangzhou 225127, China)
Abstract: To improve the ductility and formability of the Mg-3Al-1Zn alloy sheets, novel turned bearing extrusion (TBE) dies are designed based on the conventional extrusion (CE) die. Finite element simulations are performed to catch the distributions of strains and temperature fields during extrusion. The results show that gradient distribution of strain along the normal direction (ND) in TBE dies leads to the gradient microstructure. Furthermore, the transversal direction (TD)-preferred texture with ND-oriented grains deflecting toward extrusion direction (ED) is achieved. The TD-preferred texture is generated by the more activated non-basal slips in the TBE due to the higher temperature at a higher strain than that in the CE die. Because of the texture modification, the ductility and bendability of the TBE sheets. The elongation of the TBE-6 sheet reaches 33% and the bending angle reaches 83.5° when the sample is tested along 45° direction.
Key words: turned bearing extrusion; TD-preferred texture; plasticity; bendability; gradient grain size