RASTER METHODOLOGY, APPARATUS AND SYSTEM FOR ELECTRON BEAM LAYER MANUFACTURING USING CLOSED LOOP CONTROL

摘要

A method for layer-by-layer manufacturing of a three-dimensional work piece, including: (a) delivering a metallic feed material into a feed region; (b) emitting an electron beam; (c) translating the electron beam through a first predetermined raster pattern frame that includes: (i) a plurality of points within the feed region; and (ii) a plurality of points in a substrate region that is outside of the feed region; (d) monitoring a condition of the feed region or the substrate region for the occurrence of any deviation from a predetermined condition; (e) upon detecting of any deviation, translating the electron beam through at least one second predetermined raster pattern frame that maintains the melting beam power density level substantially the same, but alters the substrate beam power density level; and (f) repeating steps (a) through (e) at one or more second locations for building up layer-by-layer.

主权项

1. A closed loop control method for layer-by-layer manufacturing of a three-dimensional metallic work piece, comprising the steps of:
a) delivering a metallic feed material in a substantially solid state into a feed region, the metallic feed material being a transition metal or an alloy thereof; b) emitting an electron beam; c) translating the electron beam through a first predetermined raster pattern frame in an x-y plane that includes:
(i) a plurality of points within the feed region sufficient so that the metallic feed material is subjected to a melting beam power density level sufficient to cause melting of the metallic feed material and formation of a molten pool deposit; and(ii) a plurality of points in a substrate region that is outside of the feed region; d) monitoring a condition of one or both of the feed region or the substrate region substantially in real time for the occurrence of any deviation from a predetermined condition, with such monitoring being performed by a detector including a camera, an electron phenomena detecting mechanism or a combination of both; e) upon detecting of any deviation, translating the electron beam through at least one second predetermined raster pattern frame in the x-y plane so that the monitored condition returns to the predetermined condition; f) varying a feed rate of the metallic feed material during the step of delivering the metallic feed material; and g) repeating steps (a) through (f) at one or more second locations for building up layer by layer, generally along a z-axis that is orthogonal to the x-y plane, a three-dimensional layered metallic work piece, wherein the metallic work piece is achieved by way of a closed loop control system.