View article

Coupling a multi-scale thermo-kinetic and thermo-mechanical model with critical experiments, the present study investigates the role of process parameters on the resulting densification, cracking behavior, and microstructural evolution in laser-based powder bed fusion (LPBF) of pure tungsten. Thermal management strategies comprising shorter scan length (1 mm) and/or substrate preheating (873 K) were explored to achieve higher densities and mitigate cracks. A finite element (FE) based thermo-kinetic and thermo-mechanical computational model was developed to simulate the process spanning from the melt pool scale to the component level. FE simulations indicated pronounced heat accumulation with reduced scanning lengths. Such increased heat accumulation resulted in melt pools with larger dimensions (width and depth) and more favorable rheological characteristics resulting in printed tungsten parts …