|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Advances in Additive Manufacturing of Titanium and Titanium Based Alloys
||Understanding Light-matter Interaction, Melt Pool Dynamics and Spatter Formation in Laser Powder Bed Fusion Processing
||Manyalibo Matthews, Andrew Anderson, Nicholas Calta, Philip Depond, Gabe Guss, Saad Khairallah, Wayne King, Tien Roehling, Alexander Rubenchik, Johannes Trapp, Sheldon Wu
|On-Site Speaker (Planned)
In laser powder bed fusion additive manufacturing, complex hydrodynamics driven by vapor recoil and Marangoni convection lead to liquid metal interfaces that are steeply curved thereby affecting Fresnel absorptivity. Changes in absorptivity due to melt pool motion can lead to fluctuations in energy coupling which drive excursions in melt pool depth, microstructure and local residual stress. To clarify the complex physics involved, a laser calorimetric test bed is developed equipped with high speed optical and thermal imaging and used to study changes in energy coupling as a function of laser parameters for bulk metal plates and metal powder layers of titanium and other alloy systems. Hydrodynamic finite element modeling is used to simulate the melt pool morphology and dynamics, providing insight to energy coupling, keyholing and spatter generation mechanisms. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
||Planned: Supplemental Proceedings volume