Immediate development of processing windows for selective electron beam melting using layerwise monitoring via backscattered electron detection

The availability of a reliable processing window is the basic requirement for processing new materials via selective electron beam melting (SEBM). Typically, these processing windows are derived by a time-consuming procedure comprising fabrication, metallographic preparation and analysis of standardized specimens for every parameter set. This study demonstrates the immediate development of a processing window during one single SEBM process. An electron optical image acquisition system provides the necessary information for evaluation and subsequent adaption of process parameters. It is shown that this immediate approach delivers processing windows with sufficient accuracy, while the required time is substantially reduced from weeks or even months to several hours. (C) 2019 Elsevier B.V. All rights reserved.