On-line diagnostics of the melt surface dynamics during layerwise melting of the metal powder

The high-speed imaging method was used to study the dynamics of the melt surface during layerwise laser melting of the metal powder. We used the experimental equipment for selective laser melting process. CO 2 -laser radiation with TEM 01 ∗ mode was focused on the surface of the powder in a spot with a diameter of 0.4 mm. The following alloy powders were used: VG-159, Inconel-718, and VKNA-1VR with a grain size distribution of 10…50 microns. The powder melting dynamics was investigated using set at an angle high frame rate video camera in a one-pulse mode and in a continuous scanning exposure mode with melted track formation.