The migration of jet materials along the collision interface with laser impact welding

The jetting process plays a vital role for the achievement of a high-quality metallurgical bond in laser impact welding (LIW) due to its cleaning effect for the collision surfaces. However, its cleaning behavior and evolution with time remained unknown. This study innovatively sputtered an Au film onto the target surface as a tracking element to visualize the migration of jet materials. The trajectory of the jetting process was also simulated utilizing the smoothed particles hydrodynamics (SPH) method. It demonstrated that the jetting process effectively cleans the backside of the wave while the front of the wave was accumulated by jet materials, which become part of the welded interface. This cleaning behavior of the jetting process promotes the understanding of the welding mechanism and the formation of the intermetallics in the vortex of the waves, which further builds the foundation of LIW.