Electron-optical in-situ crack monitoring during electron beam powder bed fusion of the Ni-Base superalloy CMSX-4

Abstract Electron beam powder bed fusion (PBF-EB) of Ni-base superalloys such as CMSX-4 is a demanding process. Using conventional PBF-EB machines, process observation done by mounting optical camera systems on viewing windows at the top build chamber. However, concomitant metallization blocks methods with increasing time. Therefore, quality evaluation normally after utilizing visual inspection or subsequent metallurgical analysis. In this work, processed using freely programmable machine an electron (ELO) imaging system. It consists four-segment ELO detector and in-house developed software. The system works reliably for almost 30 h time allows layerwise monitoring area. A comparison in-situ sample surfaces shows remarkable accordance. Furthermore, applied to exemplarily document surface cracking over long times. present study successfully demonstrates application improved control under test conditions superalloys.