extremely fine submicrometer structure obtained by
DMLS is not affected by EDD, no heat affected zone
can be observed. For low peak current, up to 33A, the
eroded surface is very smooth, free from molten reso-
lidified material or deposits. High peak current causes
instead deep craters and much of the molten mate-
rial solidifies on the hole inner surface together with
debris and residues. In general, surface finish can be
improved if an expendable metallic support is posi-
tioned below the workpiece, so that a side finishing is
carried out throughout the hole depth.
REFERENCES
Agarwal, S.C., Ocken, H. 1990. The microstructure and
galling wear of a laser-melted cobalt-base hardfacing
alloy. Wear 140: 223–233.
Arcam EBM ASTM F75 Co-Cr-Mo. www.arcam.com/