Electron Beam Solid Freeform Fabrication of Metal Parts

Abstract

A novel method for near-net-shape fabrication of large, complex metal parts without the need
\nfor specific tooling is described. Parts are built up in a layer-by-Iayer fashion by feeding raw
\nmaterial in wire form into a melt pool which is maintained with an electron beam. Several different
\nalloys have been successfully deposited using a low-energy electron beam. A model has been
\ndeveloped which permits determination ofthe melt depth and vaporization-limited power input as
\nfunctions of beam energy and travel velocity. Processing parameters obtained from experiments
\nwith low-energy electron beams can be used to predict melting behavior under the influence of
\nhigher energy beams. The process is being investigated as a possible means for manufacturing
\ncompositionally-graded components.