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:
Three-dimensional printing processes are disclosed which utilize printable fluids comprising a carrier fluid, a polymeric binder, and nanoparticles. The three-dimensional printing processes are useful for making articles from a build material powder, e.g., a ceramic, metal, metal alloy, or intermetallic powder. The nanoparticles enable low temperature interparticle bonding of the build material powder particles, e.g., by forming bridging bonds between adjacent powder particles, and/or increasing the interparticle friction between the build material powder particles to enhance the structural strength of the as-built article during a thermal treatment over at least a part of the temperature range which has as its low end the temperature at which the structural strength due to the binder becomes insubstantial and as its high end the temperature at which the structural strength due to interparticle sintering of the build material powder becomes substantial, i.e., the article's debile temperature range. Green density improvements are achievable.
Abstract:
Three-dimensional printing processes are disclosed which utilize printable fluids comprising a carrier fluid, a polymeric binder, and nanoparticles. The three-dimensional printing processes are useful for making articles from a build material powder, e.g., a ceramic, metal, metal alloy, or intermetallic powder. The nanoparticles enable low temperature interparticle bonding of the build material powder particles, e.g., by forming bridging bonds between adjacent powder particles, and/or increasing the interparticle friction between the build material powder particles to enhance the structural strength of the as-built article during a thermal treatment over at least a part of the temperature range which has as its low end the temperature at which the structural strength due to the binder becomes insubstantial and as its high end the temperature at which the structural strength due to interparticle sintering of the build material powder becomes substantial, i.e., the article's debile temperature range. Green density improvements are achievable.
Abstract:
The present invention relates to powder-layer three-dimensional printers (2) having a discrete supply hopper (340) and a recoater (20). The discrete supply hopper (340) is configured to transfer a build powder to the recoater (20) in a manner that enhances the uniformity of build powder layers that are dispensed from the recoater (20). In some embodiments, at least one of the discrete supply hopper and the powder hopper of the recoater is adapted to selectively contact the other, seal against the other, and/or have one partially inserted inside the other so as to diminish or prevent powder pluming during the transfer of build powder from the discrete supply hopper to the recoater.
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 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 presented for controlling warpage during heat treatment of a 3DPBJ article having a cavity extending inwardly from an outside surface wherein a 3DPBJ article is 3DPBJ printed from a build powder as is a 3DPBJ object which is adap ted to be contactingly insertable into the cavity of the 3DP BJ article. At least a portion of the 3DPBJ article cavity surface and/or at least a portion of the surface of the 3DPBJ object is treated to prevent the 3DPBJ object from becoming bonded to the 3DPBJ article during the heat treatment. The 3DPBJ object is inserted into the 3DPBJ article cavity and the 3DPBJ article and the 3DPBJ object are heat treated to transform the 3DPBJ article into the intended article itself and the 3DPBJ object into a heat treated 3DPBJ object. The heat treated 3DPBJ object is removed from the article.
Abstract:
Recoaters are described which are adapted for use in powder-layer three-dimensional printers. The recoaters comprise a mesh discharge device that is adapted to be selectively activated by the application of an agitation, e.g. a vibration. Such mesh discharge devices include a planar mesh, i.e. a screen or sieve, which is adapted to support a quantity of powder when the quantity of powder and the mesh are static and to dispense at least a portion of the quantity of powder when at least one of the quantity of powder and the mesh is agitated. Preferably, the mesh is disposed substantially horizontally, but may be disposed at an angle to the horizontal. Also described are powder-layer three-dimensional printers comprising such recoaters. In some embodiments, the powder-layer three-dimensional printers are adapted to space the mesh no more than about two to ten powder layer thicknesses from the top surface of the powder bed or substrate upon which a powder layer is to be deposited.
Abstract:
Apparatuses are disclosed for three-dimensionally printing reactive materials which utilize a powder spreading step followed by a binder-jet deposition step. Some such apparatuses include a binder jet three-dimensional printing device, a curing device, and a depowdering device contained within an environmental enclosure which provides an inert atmosphere sufficient to allow a reactive material to be used as a build material without fire or explosion hazards. Some such apparatuses include one or more conveying systems for moving a removable build box among the various devices. Environmental enclosures having unique designs and features are disclosed.
Abstract:
A powder layer smoothing devices adapted for use with powder-layer three-dimensional printers are described. The smoothing devices include an oscillating smoothing device that includes a leading edge adapted to cut, remove, and redistribute excess powder in a powder layer. A leveling sled follows the leading edge to trowel and compact the powder in the powder layer.