Evaluation of microstructure and micro-hardness of 410L SS coatings fabricated using laser assisted cold spraying: process development

Abstract

Automotive, marine, power generation, petrochemical and mining industries experience problems which results in huge financial constraints due to damage of the engineering components. Sometimes the components are exposed to aggressive, corrosive, contaminating and erosive environments which accelerate the degradation of these components. Surface coatings are generally used to protect and prolong the lifetime of the parts. Laser Assisted Cold Spray (LACS) is a relatively new surface coating process which can be used to protect surfaces of engineering components against these aggressive environments. LACS is a hybrid process that combines the supersonic powder stream with laser heating of the deposition zone. In this process, the deposited particles and the substrate are not melted by the laser beam, but heated to just below the melting. Since no melting is involved, it is referred to “Laser Assisted Cold Spraying”. LACS technique is an emerging mainstream process; which means there are gaps in the knowledge base relating to LACS-dependent applications. This paper will focus on the microstructural evolution, mechanical deformation, the correlation between functional properties and process parameters necessary for the development of required LACS coatings. This paper will provide the basis on which research will follow-on-research that will lead to the development of high-productivity LACS coatings for identified industrial applications. The investigation of the effect of varying experimental parameters such as laser power, laser travel speed and powder feed rate on coating deposition efficiency, microstructure evolution and micro-hardness of the deposited