Influential mechanisms on interface bonding of hot-rolled TB9/TC4 laminated composites

To promote the application of laminated composites with high strength and plasticity in armor field, the feature of interface bonding and the influential mechanisms accounting for the interface quality need clarification. In this work, laminated composites of high-strength TB9 and good-toughness TC4 were successfully manufactured by high temperature rolling with different thickness reduction. Microstructural observations indicate that the plastic deformation and recrystallization at the edge position of the laminated composites are greater than that at the center position. By contrast, the center position of the composites has better bonding quality than the edge position. Besides, holes are detected at the interfaces when the reduction is low. With the reduction increased, the interface bonding is improved and the positional quality difference of the interfaces is reduced. The shear and tensile tests show higher bonding strength and tensile strength with larger rolling reduction. LS-DYNA finite element simulation is performed to study the formation mechanism of the holes and the influential mechanisms on the positional difference in interface bonding quality of the laminated composites. A parameter δ considering the relative strain of the TB9 and TC4 is introduced to quantitatively evaluate the deformation coordination. When the reduction was 70%, the δ is the smallest with the largest bonding strength up to 676 MPa at the center position.