Parametric investigation and optimization for CO2 laser cladding of AlFeCoCrNiCu powder on AISI 316

Abstract

The purpose of the current investigation is to analyze the effect of the operating parameters of laser-assisted cladding process on clad height, clad depth, clad width and the percentage dilution in a cladding of AlFeCuCrCoNi high-entropy powder on SS-316 through CO2 laser and to optimize the cladding process parameters for optimum dilution. The experiments were designed by the full factorial method and analyzed by ANOVA. The analysis results indicate that dilution is most influenced by scanning speed followed by the powder feed rate. The outcomes of the single clad profile in terms of dilution, microhardness, composition and the microstructures produced in various cladding conditions are investigated briefly, and through which the optimum set of laser cladding operating parameters for maximum hardness of the clad material is determined. The optimum cladding conditions in the experimental range were obtained at 4 g/min powder feeding rate, 500 mm/min laser scanning speed and 1.1 kW laser beam power through multi-response optimization. Furthermore, the multi-track coating with 60% overlapping ratio was deposited using optimized parameters. The wear behavior of multi-track coating was determined using pin on disk wear apparatus with applied load of 20 N, sliding speed of 300 RPM and test duration of 15 min. The pin on disk wear test results indicates that the friction coefficient of SS-316 is larger than that of high-entropy alloy cladded SS-316. The wear resistivity of SS-316 improved by 40.35% after laser-assisted high-entropy alloy coating, which confirms that the laser cladding layer plays an essential role in enhancing the wear resistance capability of austenite steel.

Keywords

• laser cladding
• high-entropy alloy
• microhardness
• wear