Heating Behavior of Cold Spray Particles in Laser

Laser-assisted cold spraying (LACS) is garnering significant interest as an innovative surface treatment technology that integrates cold spray technology with laser. However, the primary role of laser on in-flight particles remains underexplored. This study aims to elucidate the impact of laser on in-flight particles through meticulously designed experiments and comprehensive multi-physical field simulations, in which the in-flight iron and nickel particles were heated by the laser parallel to the substrates and deposited on the substrates, while the substrates were not heated by the laser. The cross-sectional microstructures, porosity, oxygen content and microhardness of the coatings were characterized to assess the effect of the laser on the in-flight particles. The heating behavior of the in-flight particles under varying velocity and laser power was evaluated using multi-physical field simulations. The results indicated that the microstructures and properties of the coatings, including porosity, flattening ratios, oxygen content and microhardness, were not significantly influenced by the laser irradiation. The simulations further revealed that the laser irradiation had negligible effect on the temperature variation of the in-flight particles, attributed to the short duration time of laser exposure. The investigation enhances our understanding of the mechanism of LACS.