Influence of spinning on the microstructure and mechanical properties of AZ91 alloy tubes

After being subjected to spinning, the evolution of microstructure, texture, mechanical properties of the AZ91 alloy tube during the spinning process was investigated in the present work. The research results indicate that the grains of the AZ91 alloy are significantly refined after spinning. Moreover, a notable grain size difference appears between the inner and outer layers. As the spinning process proceeds, the efficiency of grain refinement in the inner is gradually enhanced, resulting in a reduction in the grain size difference between the inner and outer. The C-axis rotates along RD in the majority of the grains during spinning, resulting in a strong basal texture in the AZ91 alloy tube. Nevertheless, the texture intensity initially increases and then decreases as the spinning process continues. Spinning endows the AZ91 alloy tube with better mechanical properties, the ultimate tensile strength and elongation of which can reach 300 MPa and 13.5 %, respectively, at a spinning deformation of 69 %.