Effect of Laser Cladding Parameters in Laser Direct Metal Deposition (LDMD) of Martensitic Stainless Steel Powder on Ductile Cast Iron
H. Aydin, M. Altay, A. Karşi, D. Ergin, A. Onayli and A. Bayram
Laser cladding is an additive manufacturing (AM) method based on melting the powder material using a laser beam and penetrating the substrate. In this study FGS600-3A ductile cast iron base material was used in sheet metal forming moulds was clad with 42C martensitic stainless steel powder. The effect of laser power and scanning speed process parameters were investigated on cladding quality in terms of porosity. Porosity on the cladding was analysed quantitatively with the digital image processing method. Also, the stresses and distortions on the cladding were simulated with Simufact Additive software. Optimum process parameters for minimum porosity were analysed using Regression Analysis, Factor Regression, and Response Surface Regression methods. Lower laser power and higher scanning speed, namely lower energy input, have led to lower porosity and distortion. The welding parameters of 1.37 kW laser power and 14 mm/s scanning speed (corresponding to 32.62 J/mm2 energy input) were obtained as an optimum process parameters for minimum porosity. The results obtained from the simulation study: Higher energy input resulted in greater distortion, effective and principal stresses. In three layers-multi rows, equivalent and maximum principal stresses occurred at the regions between the cladding rows, especially at sub layers. On the other hand, the distortion was greater in the upper layers, where the stresses are lower.
Keywords: High power diode laser (HPDL), ductile cast iron, martensitic stainless steel powder, laser cladding, laser direct metal deposition (LDMD), process parameters, porosity, optimization