Laser-based powder bed fusion (LB-PBF) as-built material properties; residual stresses and final component shape are dependent on the thermal history of the printed part. Design and optimization of the deposited material thus far depends on experimental trial and error. A systematic approach based on model informed optimization is missing; mainly due to the computational expense of resolving the scan path and performing the required transient simulations. In this work; the heat conduction equation is reformulated to enable accelerated simulations. The laser position and operating conditions are read from the build file. The laser trajectory throughout the component is resolved providing 3D temperature evolution. Simple demonstration parts exhibiting both hot and cold regions are used to induce different metallurgical responses of the deposited IN718. Thermocouples are used to validate calculated temperatures. CALPHAD based calculations utilize temperature predictions to obtain localized phase concentrations and predict the distribution of thermophysical properties throughout the build. Results are compared with hardness measurements confirming the accuracy of the overall modelling chain.
additive manufacturing; thermal history; modeling; phase transformation; IN718; mechanical properties