A numerical study on parameter control for remelted coating processes

A parametric finite element analysis was carried out to investigate the relation between processing parameters in remelted coating processes (e.g. remelting power, beam diameter, and scanning speed) and thermal behavior of the coating/substrate system such as dilution, melt pool, and heat affected zone. In the simulation, nickel-based alloys and alumina are studied as coatings deposited on AISI 1040 carbon steel substrate. A wide range of processing parameters are investigated. Scanning speed ranges from 5 to 100mm/s. Machining beam radius is taken from 0.5 to 3mm. It is found that the dilution is very sensitive to the re-melting power, scanning speed and machining beam radius. The role of the preheating temperature of the coating/substrate system is also considered. Significant reductions in remelting power of around 20%, 30% and 40% can be seen when the coating/substrate system is preheated at 250, 500 and 750°C, respectively. Numerical results provide useful suggestions for a re-melting process in practice.