Hot roll bonding between commercially pure titanium and high-strength low-alloy steel using Fe interlayer

Abstract

Hot roll bonding was carried out between commercially pure titanium TA2 and high-strength low-alloy steel Q390 using no interlayer and Fe interlayer at temperatures of 850, 900, 950 and 1000 °C with a total reduction ratio of 86.7%. Interfacial microstructure and bonding property of clad plates were investigated by electron microscopy and shear test. The results showed that with the increase in heating temperature, the shear strength of titanium clad steel plates decreases obviously. Compared with that of titanium clad steel plates with no interlayer, inserting Fe interlayer between titanium and steel can improve the shear strength at 850 and 900 °C but deteriorate the shear strength at 950 and 1000 °C. The reason for this consequence was that Fe interlayer prevented the reaction diffusion of C in titanium to form a thinner TiC layer at 850 and 900 °C, while Fe interlayer promoted the reaction diffusion of Fe in titanium to generate thicker Fe2Ti and FeTi intermetallic compound layers at 950 and 1000 °C.