Effect of hot rolling thinning temperature on the interfacial microstructure and mechanical properties of titanium/steel composite plates

Abstract

This study investigated the hot rolling of titanium-steel clad plates, produced via roll bonding, at four temperatures: 850, 900, 950, and 1000 °C. The aim was to produce thin-gauge titanium-steel clad plates with a total thickness of 2 mm. Interfacial compounds were analyzed using scanning electron microscopy (SEM), backscattered electron imaging (BSE), electron backscatter diffraction (EBSD), and X-ray diffraction (XRD). The mechanical properties of the interface were evaluated through microhardness, tensile shear, and tensile tests. The results showed that both the thickness of the intermetallic compound (IMC) layer and the depth of elemental diffusion increased with rolling temperature in the 850–1000 °C range. Bonding strength peaked at 218 MPa at 900 °C but decreased significantly at higher temperatures, dropping to 162 MPa at 1000 °C. The clad plate hot-rolled at 900 °C exhibited the highest tensile strength of 543 MPa. At temperatures above 950 °C, the formation of brittle compounds led to a predominantly brittle fracture mechanism on the titanium side.