Abstract:
A consumable filament for use in an extrusion-based additive manufacturing system, where the consumable filament comprises a core portion of a first thermoplastic material, and a shell portion of a second thermoplastic material that is compositionally different from the first thermoplastic material, where the consumable filament is configured to be melted and extruded to form roads of a plurality of solidified layers of a three-dimensional object, and where the roads at least partially retain cross-sectional profiles corresponding to the core portion and the shell portion of the consumable filament.
Abstract:
A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder comprises a plurality of materials having different dissociation or bonding temperatures. The powder preferably comprises blended or coated materials.
Abstract:
An apparatus and method for producing parts by selective laser sintering are disclosed. The disclosed method selectively sinters a first layer of heat-fusible powder by directing a laser beam so that it scans the first layer in a first direction to sinter a first cross-section of the part. A second layer of the heat-fusible powder is then disposed over the first layer, and the next cross-section of the part is selectively sintered by the laser being scanned in a different direction from the first direction, for example in a direction perpendicular to the first direction. The cross-scanning resulting from scanning in different directions provides parts with structural strength which is not dependent upon orientation, with more uniform surfaces and textures, and with reduced distortion. In addition, each of the layers may have its outlined traced prior to the scanning, to further define the edges of the cross-section.
Abstract:
A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched onto sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder comprises a plurality of materials having different dissociation or bonding temperatures. The powder preferably comprises blended or coated materials.
Abstract:
A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder comprises a plurality of materials having different dissociation or bonding temperatures. The powder preferably comprises blended or coated materials.
Abstract:
A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder dispensing mechanism includes a drum which is moved horizontally across the target area and counter-rotated to smooth and distribute the powder in an even layer across the target area. A downdraft system provides controlled temperature air flow through the target area to moderate powder temperature during sintering.
Abstract:
A consumable filament for use in an extrusion-based additive manufacturing system, where the consumable filament comprises a first portion of a first semi-crystalline polymeric material, and a second portion of a second semi-crystalline polymeric material, and where the second semi-crystalline polymeric material has a crystallization temperature that is greater than a crystallization temperature of the first semi-crystalline polymeric material.
Abstract:
A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder comprises a plurality of materials having different dissociation or bonding temperatures. The powder preferably comprises blended or coated materials.
Abstract:
A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder is deposited to the target area of the laser and attains high bulk density during sintering.
Abstract:
A consumable filament for use in an extrusion-based additive manufacturing system, where the consumable filament comprises a core portion of a first thermoplastic material, and a shell portion of a second thermoplastic material that is compositionally different from the first thermoplastic material, where the consumable filament is configured to be melted and extruded to form roads of a plurality of solidified layers of a three-dimensional object, and where the roads at least partially retain cross-sectional profiles corresponding to the core portion and the shell portion of the consumable filament.