Frequency domain measurements of melt pool recoil force using modal analysis

Abstract Recoil pressure is a critical factor affecting the melt pool dynamics during Laser Powder Bed Fusion (LPBF) processes. depresses pool. When recoil low, thermal conduction and capillary forces may be inadequate to provide proper fusion between layers. However, excessive can produce keyhole inside pool, which associated with gas porosity. Direct measurements are challenging because it localized over an area proportionate laser spot size producing force in mN range. This paper reports vibration-based approach quantify exerted on part commercial LPBF machine. The measured consistent estimates from high speed synchrotron imaging of entrained particles, results show that scales applied power inversely related scan speed. These facilitate further studies have potential aid process development for new materials.