Mathematical prediction of melt pool geometry and temperature profile for direct energy deposition of 15Cr5Ni SS alloy

Direct energy deposition is one of the 3D printing processes for fabricating functional parts for various engineering applications. The effectiveness of the process primarily depends on the set of process parameters and the melt pool quality. Prediction of melt pool geometry can give an edge in controlling the geometrical features of fabricated parts. In this article, a mathematical model from Toyserkani was used to predict the dimensional characteristics of the melt pool, temperature distribution, and microstructural phenomena in a laser-assisted direct energy deposition (DED) 15Cr5Ni alloy on a 304L SS substrate. The present study aims to assimilate the benefits of the Toyserkani model and inspect the effect of assumptions made on the predicted results. Predicted melt pool physical characteristics from the model and measured clad geometry from experiments were compared for the given range of process parameters ( P = 200–600 W, V = 300–500 mm/min, and f = 3–5 g/min), and the graphical interpretations were made using the commercial MATLAB 9.10 software. A non-linear relation between analytical and experimental output was observed for the melt pool geometry and temperature profile within the cladding. At some critical scan speed, melt pool depth has its ultimate value, after which it decreases. Due to assumptions and thermo-mechanical property difference, the clad height value showed a deviation in the experimental and prediction model for the energy density of 104–108 J/mm 2 . The results from the Toyserkani model were reasonably similar to those of the experimental and could predict the melt pool characteristics with improved accuracy. The application of this study can predict the clad features analytically, thus enabling the explanation of the dependence of melt pools on process parameters.