Measurement and Validation for Electron Beam Melting

Abstract

Magnetic lenses are crucial components in the electron beam melting process used for 3d-printing at Arcam. Validating that the lenses going into machine production are within specification is important. Therefore, this thesis has modified and confirmed a measurement setup, the field mapper, to be used for measurement and validation of magnetic lenses. The field mapper was then used to investigate normal behaviour of the focus and deflection lenses going into machine production as well as recreating defects of faulty lenses of the deflection and astigmatism lens to ascertain if machine integrity is compromised for respective defect. The focus lens revealed a non-significant spread, the deflection lens presented a wider spread that is easily compensated for in the machine calibration process, and for the comparison between an astigmatism lens to the same lens with an introduced winding error a significant change in the centre of zero-field was seen.