Analysis of melt pool temperature and stresses in laser cladding of inconel 718

Abstract

The present study is on numerical modeling of melt pool temperature distribution and stresses developed during the process of laser cladding (LC) Inconel 718 alloy. A model consisting of Inconel 718 as the cladding material and SS316 as substrate material is generated in COMSOL 5.4 Multiphysics software and applied the necessary boundary conditions to estimate the temperature distribution. The heat transfer physics estimates the temperature distribution while the solid mechanics coupled to heat transfer via. thermal expansion gives the stress distribution, which is obtained by the temperature difference in the model. Simulations were carried out to investigate the melt pool temperatures generated during cladding with varying process parameters (laser power, scanning speed) and further validated with experiments; while the stresses are estimated only through numerical models. From the results, it is observed that increase in laser power and decrease in scanning speed increases the melt pool temperature at the upper surface region of the substrate. An average error of about 7.0 % is obtained with the experimental results, indicating that the model developed is reliable for laser cladding process.