Laser Assisted Cold Spray (LACS) as an Alternative to HVOF, Plasma, and Helium-Based Cold Spray

HVOF, atmospheric plasma, and cold spray coatings have been traditionally used to provide wear and corrosion resistant coatings. HVOF and plasma are inefficient processes with low deposition rates, which results in excessive wastes and expensive operational costs. Cold spray requires substantially less heat than HVOF or plasma; however, cold spray powders bond via kinetic energy, and therefore, expensive gases such as helium with a high speed of sound generally produce higher gas and particle velocities which are required to achieve effective bond strengths. Recently, the cost of helium has become so excessive that performing cold spray repairs with helium is cost ineffective.

ES3 is working with Laser Fusion Technologies (LFT) to integrate a 4 kW laser into a high-pressure cold spray system. The combined system forms a LACS system that prepares the substrates immediately prior to impact of cold spray particles. The LACS process results in increased bond strengths, potential for structural repairs, and eliminates the need for using helium as the gas medium for transporting cold spray particles. ES3 is proving out this technology by optimizing the process and performing typical aircraft related metallurgical and mechanical testing to validate airworthiness considerations. ES3 will implement this technology into a US Air Force facility as part of the current effort.