Parameter Selection in Laser Assisted Cold Spray on Hard Substrates

Laser assisted cold spray is an innovative technique that uses very short, localized, heat inputs to thermally soften the substrate immediately prior to particle impact. This localized softening allows for improved bonding with minimal effect on the overall condition of the substrate. Management of this heat input is crucial for the quality of adhesion, especially on hard substrates prone to oxidation or embrittlement due to phase transformations. This work explores how different substrate materials require different heat inputs to achieve high adhesion strength, as measured by ASTM C633 pull tests. It is shown, that to develop adhesion strength in AISI 4140 low alloy steel similar to that of . Microstructural and hardness analysis highlights the extent of phase transformations occurring in both alloys as a function of laser scanning parameters.