A polymer composition suitable for manufacturing of isotropic three-dimensional printed articles, the composition including: a matrix phase including a propylene-based polymer or copolymer; and a dispersed phase in the matrix phase, the dispersed phase including an ethylene-based copolymer having a C3-C12 comonomer, wherein the dispersed phase has a different composition than the matrix phase, wherein the matrix phase has a crystallization half-time of less than 60 minutes.

A three-dimensional (3-D) printer includes build and support material development stations positioned to transfer layers of build and support materials to an intermediate transfer surface. The intermediate transfer surface transfers a layer of the build and support materials to a platen each time the platen contacts the intermediate transfer surface. A sensor detects the thickness of the layer on the platen, and a mechanical planer is positioned to contact and level the layer on the platen as the platen moves past the mechanical planer. Additionally, a feedback loop is electrically connected to the sensor and the mechanical planer. The mechanical planer adjusts the amount of the build material and the support material removed from the layer based on the thickness of the layer on the platen, as determined by the sensor.

A three-dimensional (3-D) printer includes build and support material development stations positioned to transfer layers of build and support materials to an intermediate transfer surface. The intermediate transfer surface transfers a layer of the build and support materials to a platen each time the platen contacts the intermediate transfer surface. A sensor detects the thickness of the layer on the platen, and a mechanical planer is positioned to contact and level the layer on the platen as the platen moves past the mechanical planer. Additionally, a feedback loop is electrically connected to the sensor and the mechanical planer. The mechanical planer adjusts the amount of the build material and the support material removed from the layer based on the thickness of the layer on the platen, as determined by the sensor.

A three-dimensional selective repairing system, which is for selectively repairing an area of an unrepaired element by sintering, includes a scanning device, a comparing device, a spraying device and a sintering device. The scanning device is for scanning the area to obtain a repairing data. The comparing device is connected to the scanning device to receive the repairing data and produce a repairing parameter. The spraying device is controlled by the repairing parameter and includes an electrostatic generator which sprays a plurality of electrified pulverulent bodies through the electrostatic generator to form an electrified pulverulent film on a medium covered on the area. The sintering device is controlled by the repairing parameter to provide a power beam to selectively heat the electrified pulverulent film. The electrified pulverulent film melted or sintered to form a solid mass on the area.

A three-dimensional selective repairing system, which is for selectively repairing an area of an unrepaired element by sintering, includes a scanning device, a comparing device, a spraying device and a sintering device. The scanning device is for scanning the area to obtain a repairing data. The comparing device is connected to the scanning device to receive the repairing data and produce a repairing parameter. The spraying device is controlled by the repairing parameter and includes an electrostatic generator which sprays a plurality of electrified pulverulent bodies through the electrostatic generator to form an electrified pulverulent film on a medium covered on the area. The sintering device is controlled by the repairing parameter to provide a power beam to selectively heat the electrified pulverulent film. The electrified pulverulent film melted or sintered to form a solid mass on the area.

A microdroplet-based three-dimensional (3D) laser printing system, which includes a laser beam subsystem, a transparent donor substrate, voxel arrays, and the receiver substrate. By irradiating the voxel array with a pulsed laser beam deriving from the laser beam subsystem through the transparent donor substrate, the voxel array is melted and driven away from the transparent donor substrate to generate the ejecting microdroplet array and then deposited onto the receiver substrate. The 3D microstructure is printed in parallel by sequentially irradiating the voxel array and controlling the depositing locations of microdroplet arrays onto the receiver substrate. The system can avoid the satellite microdroplets generating, improve the printing efficiency and resolution, and obtain a wide process window.

Embodiments of the present disclosure are drawn to additive manufacturing apparatus and methods. An exemplary additive manufacturing method may include forming a part using additive manufacturing. The method may also include bringing the part to a first temperature, measuring the part along at least three axes at the first temperature, bringing the part to a second temperature, different than the first temperature, and measuring the part along the at least three axes at the second temperature. The method may further include comparing the size of the part at the first and second temperatures to calculate a coefficient of thermal expansion, generating a tool path that compensates for the coefficient of thermal expansion, bringing the part to the first temperature, and trimming the part while the part is at the first temperature using the tool path.

In an illustrative implementation of this invention, a 3D object comprises substrate layers infiltrated by a hardened material. The 3D object is fabricated by a method comprising the following steps: Position powder on all or part of a substrate layer. Repeat this step for the remaining substrate layers. Transform the powder into a substance that flows and subsequently hardens into the hardened material. The hardened material solidifies in a spatial pattern that infiltrates positive regions in the substrate layers and does not infiltrate negative regions in the substrate layers.

A 3D object according to the invention comprises substrate layers infiltrated by a hardened material. The 3D object is fabricated by a method comprising the following steps: Position powder on all or part of a substrate layer. Repeat this step for the remaining substrate layers. Stack the substrate layers. Transform the powder into a substance that flows and subsequently hardens into the hardened material. The hardened material solidifies in a spatial pattern that infiltrates positive regions in the substrate layers and does not infiltrate negative regions in the substrate layers. In a preferred embodiment, the substrate is carbon fiber and excess substrate is removed by abrasion.

A method of manufacturing an integral impeller and motor rotor. The method includes manufacturing an impeller with a shroud, modifying a radially outer surface of the shroud to prepare the radially outer surface for additive manufacturing, additively manufacturing a motor rotor onto the radially outer surface of the shroud such that the motor rotor has a magnetic field with a geometry designed by computer modeling, and magnetizing the rotor.