Microstructure and Mechanical Behavior of TA2/TC4 Titanium Alloy Composites Fabricated by Explosion Welding + Rolling

Based on the characteristics of high-strength titanium alloys with high strength but poor toughness, and high-toughness titanium alloys with low strength but good toughness, high-strength and high-toughness TA2/TC4 titanium alloy composites were prepared by the method of explosive welding followed by rolling. The microstructure of the bonding interface was characterized, and the properties of the composites were tested by tensile, shear, and bending experiments. And the failure behavior of the samples was analyzed to reveal the correlation mechanism between microstructure and mechanical behavior. The results show that the interface of the explosively welded TA2/TC4 titanium alloy composite presents a wavy morphology, while the rolled interface shows an approximately straight morphology. Dynamic recovery and recrystallization occur at the interface, and the matrix grains exhibit columnar or rod-like elongation. The tensile strength of the TA2/TC4 composite ranges from 780 to 801 MPa, and the bending strength ranges from 1142.58 to 1267.19 MPa. The shear strength of the bonding interface ranges from 134 MPa to 185 MPa, showing a discrete state. Explosive welding + rolling can realize the preparation of high-strength and high-toughness composite materials of different thicknesses, providing a new approach for the preparation of various high-strength and high-toughness metal composite materials.