Abstract: The present invention relates to apparatuses for distributing build powder in powder-layer three-dimensional printers (2) and for the collection of particulates of the build powder that have become suspended in the gaseous atmosphere in the vicinity of the build platform of the three-dimensional printer. These apparatuses include recoaters (20) that are particularly useful in providing uniform distribution of fine build powder across the width of the build platform or powder bed. The present invention also includes powder-layer three-dimensional printers (2) which comprise such apparatuses for distributing build powder and/or apparatuses for collecting such suspended particulates. The improved fine powder recoater (20) uses an ultrasonic transducer (30) to move powder through a sheet screen (28). The sheet screen (28) may be presented to the powder fed onto it in a narrow dispensing slot to limit the flow rate of powder from the dispenser and to provide control over the amount of powder dispensed.

Abstract: A method for binder jetting additive manufacturing of an object, the method comprising: (i) separately feeding a powder from which said object is to be manufactured and a solution comprising an adhesive polymer dissolved in a solvent into an additive manufacturing device, wherein said adhesive polymer is an amine-containing polymer having a molecular weight of at least 200 g/mole and is present in said solution in a concentration of 1-30 wt % to result in said solution having a viscosity of 2-25 mPa·s and a surface tension of 25-45 mN/m at room temperature; and (ii) dispensing selectively positioned droplets of said adhesive polymer, from a printhead of said additive manufacturing device, into a bed of said powder to bind particles of said powder with said adhesive polymer to produce a preform having a shape of the object to be manufactured.

Abstract: A method for binder jetting additive manufacturing of an object, the method comprising: (i) separately feeding a powder from which said object is to be manufactured and a solution comprising an adhesive polymer dissolved in a solvent into an additive manufacturing device, wherein said adhesive polymer is an amine-containing polymer having a molecular weight of at least 200 g/mole and is present in said solution in a concentration of 1-30 wt % to result in said solution having a viscosity of 2-25 mPa·s and a surface tension of 25-45 mN/m at room temperature; and (ii) dispensing selectively positioned droplets of said adhesive polymer, from a printhead of said additive manufacturing device, into a bed of said powder to bind particles of said powder with said adhesive polymer to produce a preform having a shape of the object to be manufactured.

Abstract: The present invention relates to apparatuses for distributing build powder in powder-layer three-dimensional printers (2) and for the collection of particulates of the build powder that have become suspended in the gaseous atmosphere in the vicinity of the build platform of the three-dimensional printer. These apparatuses include recoaters (20) that are particularly useful in providing uniform distribution of fine build powder across the width of the build platform or powder bed. The present invention also includes powder-layer three-dimensional printers (2) which comprise such apparatuses for distributing build powder and/or apparatuses for collecting such suspended particulates. The improved fine powder recoater (20) uses an ultrasonic transducer (30) to move powder through a sheet screen (28). The sheet screen (28) may be presented to the powder fed onto it in a narrow dispensing slot to limit the flow rate of powder from the dispenser and to provide control over the amount of powder dispensed.

Abstract: The present invention overcomes the problem with carbon increase described above by providing a binder for binder jetting three-dimensional printing that results in a much lower carbon increase after post-processing. The present invention also includes making articles by binder jetting three-dimensional printing using such inventive binders.

Abstract: Methods are disclosed of making metal casting molds and components thereof by the three-dimensional printing process in which an untreated sand is used as the build material and a polymer is used as a component of the binder that is printed onto the build material.

Abstract: A three-dimensional printing apparatus is disclosed has one or more troughs for receiving excess deposited particulate. Such troughs may be positioned to receive the excess deposited particulate into a particulate receiving chamber of the trough. An evacuation chamber is located at the bottom of each trough. A partition separates the evacuation chamber from the receiving chamber of the trough. The partition is selectively perforated to permit a desired amount of the particulate to flow into the evacuation chamber from the receiving chamber. The evacuation chamber is connected to a vacuum source to periodically or continuously draw ambient gas from a gas inlet to the evacuation chamber and/or from the receiving chamber through the perforations of the partition and then through the evacuation chamber toward the vacuum source to entrain an amount of the particulate and carry the entrained particulate out of the evacuation chamber.

Abstract: Methods are provided for solid free-form fabrication of an article without using a slice stack file quickly and efficiently—in terms of computational resources—converting STL files representing an article or articles to be built by SFFF without the use of a conventional slicing program. An application program interface (“API”) is used to generate a bitmap corresponding to each particular layer of the article that is to be printed directly from the article's STL file. This conversion may done essentially in real time immediately before the particular layer is to be printed. The bitmap is used in configuring the printing instructions for the SFFF printing mechanism to print that particular layer.

Abstract: A device for applying powder layers across a substrate or atop an existing powder bed is disclosed. The device has particular utility in embodiments which are adapted for use in depositing powder layers for three-dimensional printing and as part of a three-dimensional printing apparatus. The device utilizes a conveyor belt to transfer powder from a powder reservoir and deposit it upon powder bed or other substrate. In some embodiments, the device utilizes a conveyor belt in conjunction with a powder deflector to transfer powder from a powder reservoir and deposit it upon powder bed or other substrate. In some embodiments the conveyor belt has a downwardly inclined section. In some embodiments, a downwardly inclined chute is used in conjunction with the conveyor belt.

Abstract: A three-dimensional printing apparatus is disclosed has one or more troughs for receiving excess deposited particulate. Such troughs may be positioned to receive the excess deposited particulate into a particulate receiving chamber of the trough. An evacuation chamber is located at the bottom of each trough. A partition separates the evacuation chamber from the receiving chamber of the trough. The partition is selectively perforated to permit a desired amount of the particulate to flow into the evacuation chamber from the receiving chamber. The evacuation chamber is connected to a vacuum source to periodically or continuously draw ambient gas from a gas inlet to the evacuation chamber and/or from the receiving chamber through the perforations of the partition and then through the evacuation chamber toward the vacuum source to entrain an amount of the particulate and carry the entrained particulate out of the evacuation chamber.

Abstract: Methods are provided for solid free-form fabrication of an article without using a slice stack file quickly and efficiently—in terms of computational resources—converting STL files representing an article or articles to be built by SFFF without the use of a conventional slicing program. An application program interface (“API”) is used to generate a bitmap corresponding to each particular layer of the article that is to be printed directly from the article's STL file. This conversion may done essentially in real time immediately before the particular layer is to be printed. The bitmap is used in configuring the printing instructions for the SFFF printing mechanism to print that particular layer.

Abstract: Methods and systems (2) are disclosed for making articles (114) by three-dimensional printing. The methods include selectively printing by jet deposition on successive layers (4) of a build material powder (10) at least one of a first binder fluid and a second binder fluid. At least one of the first and second binder fluids includes a particulate matter (16) having mean particle size diameter which is less than that of the build material powder (10). The first binder fluid is characteristically different from the second binder fluid. The particulate matter (16) selectively deposited with a binder fluid can be used to locally tailor the physical properties of the article (114), e.g. by alloying with the build material powder, increasing densification, acting as a local infiltrant or infiltrant stop during heat treatment, locally modulating the local stress fields (e.g. by a mismatch of thermal coefficients of expansion), etc.

Abstract: Methods and systems (20) are disclosed for making articles by three-dimensional printing. The methods include three-dimensionally printing articles by selectively jet-depositing a particle-bearing binder fluid (14) upon successive layers (4) of a build material powder (10) such that the particles (16) deposited with the binder fluid (14) increase the apparent density of the as-printed article. The particulate matter (16) of the binder fluid (12) is smaller than the mean particle size of the build material powder (10). Preferably, this jet-deposited particulate matter (16) has a mean particle size that is larger than about 1 to and smaller than or equal to 50 microns. The jet-deposited matter (16) acts to fill in the interparticle interstices of the build material powder (10) thereby simultaneously increasing the density of the printed article and improving its surface roughness and contour resolution, which in turn, improves the surface finish of the final article.

Abstract: Methods are disclosed of making metal casting molds and components thereof by the three-dimensional printing process in which an untreated sand is used as the build material and a polymer is used as a component of the binder that is printed onto the build material.