Research on interfacial bonding mechanism and mechanical properties of TA1/45 carbon steel composite tubes by hot power spinning

Titanium/steel composite tubes combine the low cost, and high mechanical strength of the steel and the excellent corrosion resistance of the titanium, showing remarkable application potential in fields such as shipbuilding and petrochemical industries. However, significant differences exist in the mechanical and thermophysical properties between titanium and steel, including strength, elongation and thermal expansion coefficient. The conditions for metallurgical bonding between the two materials are relatively strict. Therefore, in this study, TA1/45 steel composite tubes were fabricated using the hot power spinning technique combined with ends welding to coordinate the deformation between the inner and outer tubes and to prevent surface oxidation. Combined with experiment and numerical simulation, the material flow pattern and stress state in typical regions during spinning was investigated, and the microstructure and phase composition of the interface were characterized. The mechanical properties of the composite tube was tested, to explain the diffusion and reaction mechanisms of interface elements, and reveal the generation mechanism and distribution characteristics of phases. Results show that the interface was tightly bonded without obvious defects, and primarily composed of an Fe 2 Ti, FeTi, and TiC. The shear and tensile strength of the composite tube were 156.3 MPa and 496.2 MPa, respectively. In addition, the elongation was close to 33.7%, indicating high bonding strength and excellent mechanical properties of the composite tube. This study serves as an important theoretical basis for developing a hot power spinning process for titanium/steel composite tubes with excellent comprehensive performance.