A process and apparatus for free form fabrication of a three-dimensional work piece comprising (a) feeding raw material in a solid state to a first predetermined location; (b) depositing the raw material onto a substrate as a molten pool deposit under a first processing condition; (c) monitoring the molten pool deposit for a preselected condition; (d) comparing information about the preselected condition of the monitored molten pool deposit with a predetermined desired value for the preselected condition of the monitored molten pool deposit; (e) solidifying the molten pool deposit; (f) automatically altering the first processing condition to a different processing condition based upon information obtained from the comparing step (d); and repeating steps (a) through (f) at one or more second locations for building up layer by layer a three-dimensional work piece. The apparatus is characterized by a detector that monitors a preselected condition of the deposited material and a closed loop electronic control device for controlling operation of one or more components of the apparatus in response to a detected condition by the detector.

Electron beam layer manufacturing

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.

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

A substantially homogeneous metal matrix composite conduction weld between first and second metal matrix composite components is formed by placing the components into abutting position, with a major portion thereof spaced from each other, and directing a laser beam through the spacing onto the intersection and oscillating the beam across the intersection to form a shallow pool of metal matrix composite while feeding a metal matrix composite filler wire into the pool. The laser beam and filler wire are moved along the intersection such that solidification of the molten pool containing the filler wire metal matrix composite is effected, to form the weld line, without separation of the metal matrix composite into separate phases. The filler wire may be preheated and pressure may be applied, either to one or both components in a direction transverse the plane of the intersection or to the weld line in the direction of the plane of the intersection.

Method for laser beam welding metal matrix composite components

@ An envelope apparatus is provided for facilitating the production of a vacuum at a localized region on the surface (30) of an article such as a semiconductor wafer. The vacuum permits vacuum processing in the localized region. The envelope apparatus includes an internal processing zone (32) in which the requisite processing level vacuum is maintained. The envelope apparatus also includes intermediate vacuum zones (34) surrounding the internal processing zone. The internal processing zone and surrounding intermediate vacuum zones are exposed at an external surface so that when the external surface is placed in spaced apart, close coupled opposition to the article being processed a graded vacuum seal is formed. The graded seal extends from the internal processing zone, past the intermediate vacuum zones and out to ambient. The envelope apparatus is held either in a fixed position with respect to the surface of the article or actively tracks the topography of the surface of the article so that the gap between the external surface and the surface of the article lies within an acceptable range. For semiconductor processing applications, it has been found that a graded seal formed by two-stage differential pumping and having a gap in the range of 20 micrometers to 40 micrometers will permit vacuums on the order of 10.5 Torr to be maintained within the interior processing zone of the envelope apparatus.

Envelope apparatus for localized vacuum processing

A disc holder assembly having a disc holder and a surface finishing disc member. The disc holder has a lower circular surface which includes a coaxial concave portion having a projection extending downwards from its center, a planar portion extending outward from the outer edge of the concave portion, and a sheet fastening member fixed to the planar annular surface. The projection includes a shaft portion and a distal head portion of larger diameter than the shaft portion. The surface finishing disc includes a surface finishing layer (e.g., coated abrasive sheet) on its lower surface, a sheet fastening member on its opposite surface and a central opening of the same diameter of the shaft portion of the projection. The opening of the disc member is forced over the head portion of the projection so that the sheet fastening members are secured as they contact to firmly hold the disc member within the disc holder.

Disc-holder assembly

An installation for the automatic grinding of surfaces, especially of body surfaces to be painted of a motor vehicle, in which the grinding aggregate is machine-guided and the grinding disk exchange at the grinding aggregate is realized automatically. For that purpose, the installation provides a grinding disk magazine, a container filled with liquid as well as a support plate. Additionally, the grinding aggregate includes within the area of its grinding wheel a clamping mechanism for the grinding disk which is actuatable hydraulically or pneumatically.

Installation for the automatic grinding of curved surfaces

A connection of an outer sheet metal member with an inner sheet metal member whereby the outer sheet metal member must form an optically smooth surface. For that purpose, the outer sheet metal member is folded over the inner sheet metal member and a welding seam is then made from the folded-over side by means of a low energy welding process, for example, special forms of the protective gas welding or energy beam welding, and more particularly in such a manner that only the folded-over part of the outer sheet metal member and the inner sheet metal member fuse. The non-folded-over side of the outer sheet metal member thereby shows no impairment whatsoever by the welded connection.

Welding seam for the connection of two thin sheet metal members

A device for compensating for spurious magnetic fields in an energy beam device includes first and second pairs of electromagnetic poles arranged along the particle path and providing magnetic fields to compensate for spurious magnetic fields which might cause the beam of charged particles to deviate from the desired beam path.

Charged particle beam processing with magnetic field compensation

A method and an apparatus for the control of the filler material supply rate in energy beam welding as electron beam welding is disclosed. The width or cross-sectional area of a gap defined by opposed faces of two workpiece parts to be joined is measured by radiation, preferably X-ray radiation, and the rate with which filler material is supplied into a welding zone produced by the energy beam is controlled in proportion to the result of the measurement. The measurement may be made in advance of the welding zone and the control is then delayed by a period of time, which the welding zone takes to arrive at the position of the gap, where the measurement was made.

Method and apparatus for control of method parameters in energy beam welding

not available for EP0177945Abstract of corresponding document: US4738560A connection of an outer sheet metal member with an inner sheet metal member whereby the outer sheet metal member must form an optically smooth surface. For that purpose, the outer sheet metal member is folded over the inner sheet metal member and a welding seam is then made from the folded-over side by means of a low energy welding process, for example, special forms of the protective gas welding or energy beam welding, and more particularly in such a manner that only the folded-over part of the outer sheet metal member and the inner sheet metal member fuse. The non-folded-over side of the outer sheet metal member thereby shows no impairment whatsoever by the welded connection.

Dieter Konig

Papers

Installation for the automatic grinding of curved surfaces

Welding seam for the connection of two thin sheet metal members

Charged particle beam processing with magnetic field compensation

Method and apparatus for control of method parameters in energy beam welding

Weld for the junction of two thin sheets