Laser Powder Bed Fusion Processing Simulation of Simple Geometries in Inconel 738

Additive Manufacturing (AM) of metals has emerged as a key discipline to produce parts that enable certain performance advantages. However, the list of available alloys for AM remains limited. Metal AM is challenging due to the high number of passes required, especially for alloys with poor weldability such as Inconel 738 (IN738). This nickel-based superalloy, with its high creep resistance, is very difficult to process commercially via AM due to cracking susceptibility. However, there is literature suggesting feasibility, although it may result in regions of high deformations and stresses. If such areas can be predicted in advance, they can be improved through design modifications. AM process simulation is a tool that enables such deformation predictions. In this work, we use a commercial simulation tool, Simufact Additive, to calibrate and predict the deformation of simple geometries produced in IN738 via laser powder bed fusion AM. Using the deformation of a printed geometry the set of inherent strains in simulation could be calibrated to match the actual printed deformation maximum. Using the calibrated inherent strains predictions on other geometries could be made and compared to their printed counterparts. Through this procedure, it was found that the inherent strain method cannot predict every form of deformation adequately. When the prediction geometries and the calibration geometries have similar main driving factors for their deformation, deformation deviations of  <20% were achieved. The prediction is less reliable when using the calibration on a deformation stemming from stress relief occurring through the cutting of a printed part.