Prediction of the efficient heat flux to get an accurate thermal and clad geometry characteristic during laser cladding

Abstract

The prediction of the accurate thermal and clad geometry characteristics plays a significant role in obtaining a better metallurgical bond between the cladding material and the substrate. The estimation of temperature distribution is difficult experimentally within the melt pool. A suitable and accurate heat flux is needed to apply during the numerical modeling to get clear and accurate process parameters before conducting the actual experiments. Therefore, different heat flux is used to get the best-suited heat flux which gives an accurate response during the laser cladding. The same processing parameters were considered during the simulation for the different heat sources. In all the cases, the maximum temperature was obtained at the center of the melt pool and decreased when moving away from the center of the melt pool in-depth and across the scanning speed direction. A similar shape of the melt pool is formed when three-dimensional volumetric Gaussian heat flux and conical heat flux are used, which gave best suited and efficient heat flux for the numerical simulation before actually conducting experiments. When egg-shaped heat flux is applied, an insufficient temperature was reached at the interface of the powder and substrate, whereas more dilution appeared for parabolic heat flux.