Numerical Simulation of Stand-Off Distance Effects on Explosive Welding Quality of Titanium-Stainless Steel

The effects of stand-off distance on explosive welding quality between titanium (TP 270C) and stainless steel (SUS 821L1) composite plates, were investigated. The 3D numerical simulations were conducted with the ANSYS/LS-DYNA software by 2 algorithms (the ALE method and the SPH-FEM coupling method) for 3 stand-off distances: 1.2 mm, 2.2 mm and 3.5 mm. The simulation results show that, for both algorithms the vertical displacements of flyer plates reach or exceed respective stand-off distances. The collision velocities and angles consistently fall within the acceptable range of the welding window. The collision velocity and angle exhibit positive correlations with increasing stand-off distances. Optimal welding quality occurs at the 3.5 mm stand-off distance. The results verify that both algorithms effectively simulate explosive welding between the TP 270C titanium alloy and the SUS 821L1 stainless steel. Stable bonding is achievable across all tested stand-off distances. Moreover, the interfacial bonding strength increases progressively with the stand-off distance, which demonstrates an enhancement mechanism in welding quality through parameter optimization.