Effect of processing parameters during the laser beam melting of Inconel 738: Comparison between simulated and experimental melt pool shape

Numerical simulation is a powerful tool to understand the link between processing parameters and solidification conditions during laser beam melting (LBM) process. To be able use this for microstructural control, numerical models need validated on large set of experimental conditions, ensure that model describes predominant physical phenomena. In study, an twenty tracks was produced in Inconel 738 alloy, with wide range energy input scanning speed. Experimental melt pool shapes were compared predictions multiphysics model. model, powder bed considered as continuum. The source modeled Beer-Lambert absorption law, surface tension, Marangoni force recoil pressure are driving forces dynamics. This kind offers efficient computational time, but requires calibration coefficient representative description laser-matter interaction. order represent correctly heat mass transfer interaction, needs account loss matter caused by ejection particles spatters. A novel method proposed calculate coefficient. uses cross sections pools simplified analytical expression balance. enabled good agreement experiments calculations process window. values obtained calibrations resulted phenomenological absorptivity parameters. Based expression, comparison made another from literature using time-consuming ray-tracing Similar results have been obtained, demonstrating potential approach predict shape thus better combined effect interaction LBM