Optimization of processing parameters in fiber laser cladding

Laser cladding of steel is a promising solution to wear and corrosion resistance, and to the improvement of the mechanical properties of the cladded surface. The properties of cladded components depended on the clad geometry. The clad geometry was governed by the processing parameters. In this study, a cored wire with a sheath made of 95 wt% Co and 5 wt% Fe, with an outer diameter of 1.2 mm and an inner diameter of 0.8 mm, was used. A full factorial design was used to optimize the processing parameters in cored wire laser cladding. The design consisted of three main factors: laser power, scanning speed, and cored wire feed rate, each at three levels in addition to the current, laser spot diameter, and stand-off distance. The response functions were clad width, height, aspect ratio (width/height), dilution ratio (penetration area/total fusion area), and the hardness. The mathematical relationships were established by statistical analysis. The optimal values of the parameters were determined from these relationships. The overlay plots were made from graphical optimization to serve as a technical reference for operators in the workshop for laser cladding with a specific material of cored wire. It was found that a laser power of 3.7 to 3.9 kW, a cored wire feed rate of 75 mm/s, and a scanning speed close to 6 mm/s were the optimal values.