Effect of Annealing Temperature on Interfacial Microstructure and Tensile Fracture Behavior of Titanium-Steel Clad Plate

To ensure that the rolled composite plate has excellent processing properties. Annealing is an effective means of modulating organization and mechanical properties. In this study, annealing treatments at different temperatures were applied to the rolled titanium-steel clad plate. The evolution of the interfacial organization was observed using scanning electron microscopy. The strain distribution of the composite plate in the tensile process was investigated using a tensile experiment combined with the DIC method. The results indicate the presence of compounds such as TiC, Fe2Ti, and FeTi after hot rolling. As the annealing temperature increases, the thickness of the interlayer diffusion of elements between the two plates increases. The geometric dislocation generated between the grains after hot rolling is significantly improved after annealing treatment, and the geometric dislocation density decreases with the increase in annealing temperature. In the titanium layer, the titanium grains, after annealing at 550 °C and 600 °C, are in the recovery stage, and the amount of recrystallization does not change significantly. However, after annealing at 650 °C, the titanium grains are completely recrystallized, the grains are equiaxed, and the grain-to-grain anisotropy is eliminated. The sample annealed at 550 °C fractures almost simultaneously in the tensile test in the titanium layer and steel layer, with an elongation of 32.3% and a tensile strength of 477.1 MPa, showing the best comprehensive performance. Based on DIC strain curve analysis, The strain curve after annealing at 550 °C is smoother, the necking is relatively consistent, and it reaches a point of relatively consistent local strain instability.