Evaluation of forming limit diagrams using Nakazima out-of-plane test and incremental forming process for two-phase magnesium–lithium alloy sheet

The focus of this paper is to investigate the formability of two-phase Mg–Li sheets through drawing forming limit diagrams (FLDs) obtained from Nakazima out-of-plane test and incremental forming process. For this goal, Mg LZ71 manufactured by casting and then as-cast ingot converted to plate by hot rolling, and finally, the sheets were annealed. Then, the microstructure of the LZ71 alloy was assessed by an optical microscope. Also, the mechanical properties of the LZ71 samples were investigated using uniaxial tensile tests. Furthermore, to achieve isotropic samples, anisotropy parameters of as-cast, as-rolled, and annealed samples were determined. Afterward, the formability of the produced LZ71 sheet was studied with the help of FLD. In the present investigation, the FLDs of the LZ71 sheet were obtained using two methods, including the Nakazima out-of-plane test and the incremental forming process. The results showed that Mg LZ71 has a dual-phase microstructure, which causes considerable formability. Also, the results showed that FLD of the Mg LZ71 sheet in incremental forming is higher than that of the conventional Nakazima test.