Raster methodology, apparatus and system for electron beam layer manufacturing using closed loop control

A dosed 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 having one or more predetermined electrical currents by employing at least one electron beam gun;
• c) translating the electron beam through a first predetermined raster pattern frame in an x-y plane that includes:
• (iii) 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
• (iv) a plurality of points in a substrate region that is outside of the feed region, sufficient so that the plurality of points outside the feed region is subjected to a substrate beam power density level that is different from the melting beam power density level;
• 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 that maintains the melting beam power density level substantially the same as the first predetermined raster pattern frame, but alters the substrate beam power density level in a manner so that the monitored condition returns to the predetermined condition;
• and
• f) repeating steps (a) through (e) 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.

A chased 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 including titanium or an alloy of anium in a wire form in a substantially solid state into a feed region;
• b) emitting an electron beam having one or more predetermined electrical currents by employing a single electron beam gun;
• c) translating the electron beam through a first predetermined raster pattern frame in an x-y plane that includes:
• (v) 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
• (vi) a plurality of points in a substrate region that is outside of the feed region, sufficient so that the plurality of points outside the feed region is subjected to a substrate beam power density level that is different from the melting beam power density level;
• 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 that maintains the melting beam power density level substantially the same as the first predetermined raster pattern frame, but alters the substrate beam power density level in a manner so that the monitored condition returns to the predetermined condition;
• and
• f) repeating steps (a) through (e) 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.