Crack Repair of Navy Components using a Portable High-Pressure Cold Spray System

This proposal is for the development of a unique, ultra-portable, low-cost, hand-held high-pressure cold spray system for repairing cracks on aluminum structures on surface ships that were damaged by corrosion, based on a patent-pending cold spray device which has already be developed for shop or laboratory based applications. In the cold spray process, powder particles are accelerated by a supersonic gas jet at a temperature lower than the melting point of the material, resulting in the formation of a metallurgically-bonded coating from particles in the solid state. Because the temperatures of the cold spray process are significantly lower than other thermal spray processes, surfaces can be easily repaired without overheating or overaging the substrate materials. The use of high-pressure cold spray (>500 psi) has been shown to be capable of producing coatings of superior mechanical strength and adhesion (>10 ksi), making it suitable for some structural applications. Furthermore, the cold spray coating can be specifically tailored to meet the corrosion requirements of the components, through an understanding of the corrosion potentials of the substrate and coating. In this way, coatings of a neutral, anodic, or even a cathodic nature can be designed and applied.