Theoretical, experimental and numerical studies on the deep drawing behavior of Ti/Al composite sheets with different thickness ratios fabricated by roll bonding

The advantages of Ti/Al composite sheet are its light weight, high specific strength, and good corrosion resistance. It can be used in aerospace, pressure vessels, and high-end kitchenware through subsequent forming. However, there is still a lack of systematic research and corresponding theoretical models on the follow-up formability of Ti/Al composite sheets. In the present study, Ti/Al composite sheets with different layer thickness ratios were obtained by adopting the cold-rolling method. The basic mechanical properties and plane anisotropy parameters were the obtained using the uniaxial tensile test. The FLCs (Forming Limit Curve) of the Ti/Al composite sheets were accurately predicted by FEM (Finite Element Method) and verified by experiments on material anisotropy and failure criteria. Moreover, considering the deep drawing process of Ti/Al composite sheets, a corresponding theoretical model was established and verified by experiments and FEM. The stress distribution and variation law of each element layer were predicted and analyzed using the theoretical model. Additionally, the process parameters and process windows that affected the formability of the parts were discussed. Finally, the matching forming die was designed, and the deep drawing experiment was carried out. The results show that the quality of the Ti/Al composite forming part is great, and the thinning and thickening rates meet the quality requirements. Thus, this systematic research helps us understand the forming law and stress distribution of Ti/Al composite sheets. Meanwhile, the established theoretical model can reduce the simulation time and promote the engineering application of Ti/Al composite sheets.