Interfacial evolution and mechanical behavior of explosively welded titanium/steel joint under subsequent heat treatment process.

Explosive welding (EXW) has advantages in joining metallurgically incompatible metals due to its high quality and simple process. Successful titanium/steel clad plates fabricated by explosive welding have been extensively reported in recent years. However, no research has been reported on the fabrication of explosively welded TA2/15CrNi3MoV clad plates and the effect of subsequent heat treatment processes on the clad plates. This study aims to clarify the microstructure evolution and mechanical behavior of explosively welded TA2/15CrNi3MoV clad plates during the subsequent heat treatment process. The explosively welded TA2/15CrNi3MoV clad plates were heat-treated in the temperature range of 700–1000 °C for 30 min. The results elucidated that the heat treatment process accelerated the interdiffusion of constituent elements (e.g., Fe, Ti, and C) at the TA2/15CrNi3MoV interface, which formed FeTi, Fe₂Ti, and TiC. For the samples heat-treated at 700 °C, a continuous TiC layer was generated at the TA2/15CrNi3MoV interface, which hampered the formation of FeTi and Fe₂Ti. However, for the samples heat-treated at 800 °C, the continuous TiC layer was broken up, which resulted in a significant increase in the Fe-Ti layer to 1.21 μm. This microstructure evolution dramatically dropped the tensile strength to 329.2 MPa. For samples heat-treated in the temperature range of 900–1000 °C, the thickness of the brittle Fe-Ti layer dramatically increased and caused a rapid drop in tensile strength. [ABSTRACT FROM AUTHOR]