Abstract: The widespread application of titanium/steel composite tubes in marine engineering and petrochemical industries has been severely restricted by the absence of efficient fabrication methods. In this study, high-strength 304 stainless steel (304SS)/TA2 composite tubes with metallurgical bonding were successfully fabricated using a three-roll skew rolling process, filling the gap in producing titanium/steel composite tubes with large length-to-diameter ratios. Based on the unique non-uniform deformation characteristics of three-roll skew rolling, this study systematically investigates the influence of temperature on interfacial microstructure and bonding strength. The results show that the bonding strength of 304SS/TA2 composite tubes first increases and then decreases within the temperature range of 60 0-80 0 ° C. Compared to traditional explosion welding ( ∼ 185 MPa) and diffusion bonding ( ∼ 150 MPa), the peak bonding strength of 247.73 MPa at 700 ° C represents a 34 % improvement. The enhanced bonding strength can be attributed to two key mechanisms: (1) The formation of a solid solution strengthening layer and β -Ti phase, which effectively im pedes strain transfer from the TA2 side to the interface, thereby delaying interfacial failure; (2) The synergistic interaction between discontinuous micron-scale β -Ti phases and nano-scale TiC particles near the interface, which collectively contribute to a multi-scale particle pinning effect, further reinforcing interfacial bonding. These findings indicate that precise temperature control during three-roll skew rolling can effectively tailor interfacial structures, providing a viable technical pathway for achieving high-strength bonding in dissimilar metal composite tubes.

Key words: Three-roll skew rolling, Composite tubes, Non-uniform deformation, Bonding strength, Interfacial microstructure, In-situ shear fracture behavior