Microstructure evolution and mechanical performance of roll-bonding interface in HAZ during arc welding of titanium/steel clad plates

Abstract

Severe damage could be caused to clad plate rolling interface during welding, resulting in poor service reliability. Here, the rolling interface of TA2/Q235 clad plate evolution was investigated by thermal simulation. The TiFe and TiFe2 compound layers generated sequentially between IFsteel and β-Ti(Fe) at 1000°C, and transformed into eutectic Fe + TiFe2 and blocky TiFe on TiFe2 at 1250°C. The island-strip Ti + TiFe eutectic structures appeared on β-Ti(Fe) at 1100°C. The shear strength drops slightly to 110 MPa with the TiFe layer generating, sharply to 30 MPa with the TiFe2 layer, then remains stable. The heat-affected zone within 2 mm from the weld is weak and unreliable.