A 3D printing apparatus is disclosed herein. The apparatus comprises a container, a build material extraction module, an energy source and a controller. The container is to receive a build volume comprising portions in which an un-cured thermally curable binder has been applied to define a 3D object to be generated and portions on which no binder has been applied. The build material extraction module is to remove part of the build material on which no binder has been applied. The energy source to heat the contents of the container. And the controller is to control the build material extraction module to remove part of the build material on which no binder has been applied; and control the energy source to heat the build material to thermally cure any binder in the container.

A geometry model is defined of a part targeted for a manufacturing operation that includes an additive process followed by a subtractive process. Potential build orientations of the geometry model used in the additive processes are defined, as are one or more removal tools of the subtractive process. For each of the potential build orientations, supports that are used by the additive process at the orientation are determined. One of the build orientations is selected that minimizes portions of one of the supports that are inaccessible via at least one of the removal tools.

A geometry model is defined of a part targeted for a manufacturing operation that includes an additive process followed by a subtractive process. Potential build orientations of the geometry model used in the additive processes are defined, as are one or more removal tools of the subtractive process. For each of the potential build orientations, supports that are used by the additive process at the orientation are determined. One of the build orientations is selected that minimizes portions of one of the supports that are inaccessible via at least one of the removal tools.

An additive layer manufacturing method, preferably using selective laser sintering, for manufacturing a solid article, the method including applying a layer of a powder, the powder including at least one powdered (co)polymer, onto a solid substrate in a processing chamber; fusing the powder layer onto the solid substrate; subsequently depositing successive layers of the powder, wherein each successive layer is selectively fused prior to deposition of the subsequent layer of powder so as to form the article. In some embodiments, the powder further includes abrasive particles having a hardness greater than or equal to that of aluminum oxide.

A three-dimensional (3D) metal object manufacturing apparatus is equipped with two solid metal moving mechanisms that are independently operated to move two different metals into the receptacle of a vessel in a melted metal drop ejecting apparatus. The ejector is operated to form object features with melted metal drops of one of the two different metals and to form support features with melted metal drops of the other of the two different metals. The thermal expansion coefficients of the two metals are sufficiently different that the support features easily separate from the object features after the object and support features cool.

A three-dimensional (3D) metal object manufacturing apparatus is equipped with two solid metal moving mechanisms that are independently operated to move two different metals into the receptacle of a vessel in a melted metal drop ejecting apparatus. The ejector is operated to form object features with melted metal drops of one of the two different metals and to form support features with melted metal drops of the other of the two different metals. The thermal expansion coefficients of the two metals are sufficiently different that the support features easily separate from the object features after the object and support features cool.

In an example implementation, a method of printing a multi-structured three-dimensional (3D) object includes forming a layer of sinterable material. The method includes processing a first portion of the sinterable material using first set of processing parameters and processing a second portion of the sinterable material using a second set of processing parameters. The processed first and second portions form, respectively, parts of a first and second structure of a multi-structured 3D object.

In one example, a 3D printing system includes a support structure generator to identify a breakaway support to temporarily support part of the object, to design a wedge shaped groove between a portion of the object and the support, the groove ending at a line along which the support intersects the object, and to generate a digital object model that includes the support and the groove. The system also includes a 3D printer to print the object, support and groove based on the object model.

In one example, a 3D printing system includes a support structure generator to identify a breakaway support to temporarily support part of the object, to design a wedge shaped groove between a portion of the object and the support, the groove ending at a line along which the support intersects the object, and to generate a digital object model that includes the support and the groove. The system also includes a 3D printer to print the object, support and groove based on the object model.

The present disclosure is directed towards a method of manufacturing a permanent magnet such that the magnet defines a channel for allowing circulation of a coolant through the permanent magnet, or defines a channel for allowing circulation of the coolant through an interface between the permanent magnet and a substrate. Magnets made by this method may be useful for manufacturing and/or operating a machine, such as a motor, engine, or sensor.