Support substrates are used in certain additive fabrication processes to permit processing of an object. For additive fabrication processes with materials that are sintered into a final part, a multi-layer support substrate of interleaved support and interface layers is fabricated to support an object while reducing an impact of friction on shrinkage of the part during the sintering process.

A method of changing the gas content of a device (100) which comprises a first chamber (110). The method comprises: arranging the device in a first configuration, wherein the first chamber has a first internal volume; providing a flow of a first gas to the first chamber so that the gas content of the first chamber is at least partially changed; transitioning the device from the first configuration to a second configuration, wherein the first chamber has a second internal volume which is grater than the first internal volume.

An additive manufacturing apparatus includes a powder layer forming portion, an energy beam source, and a contact detection sensor including a plate-like probe. The powder layer forming portion is configured to form a powder layer in a predetermined region. The energy beam source is configured to radiate an energy beam to the powder layer formed by the powder layer forming portion to fuse or sinter the powder layer so that a solidified layer is formed. Presence or absence of a projection portion on a surface of the solidified layer is detected by using the contact detection sensor.

An additive manufacturing apparatus includes a powder layer forming portion, an energy beam source, and a contact detection sensor including a plate-like probe. The powder layer forming portion is configured to form a powder layer in a predetermined region. The energy beam source is configured to radiate an energy beam to the powder layer formed by the powder layer forming portion to fuse or sinter the powder layer so that a solidified layer is formed. Presence or absence of a projection portion on a surface of the solidified layer is detected by using the contact detection sensor.

Irradiation device (5) for an apparatus (1) for additively manufacturing three-dimensional objects (2) by means of successive layerwise selective irradiation and consolidation of layers of a build material (3) which can be consolidated by means of an energy source, which Irradiation device (5) comprises at least one irradiation unit (6-8), preferably an optical unit, arranged in a housing (9) of the Irradiation device (5), wherein a stream generating device (10) is provided that is adapted to guide a gas stream (11) that is adapted to be charged with residues present inside the housing (9) through the housing (9) of the Irradiation device (5) along a streaming path in which the gas stream (11) at least partially streams alongside or through the at least one irradiation unit (6-8) for removing residues from the housing (9).

A process for manufacturing a multi-material part by additive manufacturing, includes the following steps: a) a step of providing a pre-treated metal powder comprising grains and an oxidized and porous layer on a surface of the grains; b) a selective laser powder-bed fusion step comprising implementation of steps i) and ii) as follows: i) a step of forming a layer from the pre-treated metal powder; ii) a step of melting by laser the layer, the melting step being carried out under a reactive atmosphere and comprising changing parameters of application of the laser so that at least a first region of the layer is converted so as to lower the electrical conductivity thereof, thus forming a dielectric, and so that at least a second region of the layer is densified without converting it, the at least a first region being formed when the parameters of application of the laser allow a first energy density to be applied to the first region and/or the laser beam to be kept for a first dwell time on the first region, the at least a second region being formed when the parameters of application of the laser allow a second energy density to be applied to the second region and/or the laser beam to be kept for a second dwell time on the second region, and the first energy density being higher than the second energy density and/or the first dwell time being longer than the second dwell time. A part obtained using the process is also provided.

An apparatus (100) for additive manufacturing of a part of an article from a first material comprising particles having a first composition is provided. The apparatus (100) comprises a layer providing means (110) for providing a first support layer from a second material comprising particles having a second composition, wherein the first composition and the second composition are different. The apparatus (100) comprises a concavity defining means (120) for defining a first concavity in an exposed surface of the first support layer. The apparatus (100) comprises a depositing means (130) for depositing a part of the first material in the first concavity defined in the first support layer. The apparatus (100) comprises a levelling means (140) for selectively levelling the deposited first material in the first concavity. The apparatus (100) comprises a first fusing means (150) for fusing some of the particles of the levelled first material in the first concavity by at least partially melting said particles, thereby forming a first part of the layer of the article. In this way, the second material may be thus used to provide a support structure during additive manufacturing of the part of the article.

An example of a method, for three-dimensional (3D) printing, includes applying a build material and patterning at least a portion of the build material. The patterning includes selectively applying a wetting amount of a binder fluid on the at least the portion of the build material and subsequently selectively applying a remaining amount of the binder fluid on the at least the portion of the build material. An area density in grams per meter square meter (gsm) of the wetting amount ranges from about 2 times less to about 30 times less than area density in gsm of the remaining amount.

An additive manufacturing machine (900) includes a build unit (904) that is supported by an overhead gantry (918). The build unit (904) includes a powder dispenser (906) including a vibration mechanism (922) and a scan unit (908) including a powder fusing device (910) for fusing or binding portions of a layer of additive powder. A vibration isolation device (932), such as a passive rubber damper (940) or an active vibration canceling mechanism (960), is positioned between the powder dispenser (906) and the scan unit (908) to prevent vibrations in the powder dispenser (906) from causing operational issues with the scan unit (908) and inaccuracies in the additive manufacturing process.

The invention relates to a seal system (100, 200, 300) for an installation (400) for producing a three-dimensional workpiece by means of an additive layer manufacturing method, the seal system (100, 200, 300) comprising: a first seal (102), which is configured to seal an intermediate space (116) at a first periphery (108) between a process chamber inner wall (110) and a powder-material-supporting plate assembly (112) in a process chamber (410) of the installation (400); and a second seal (104), which is configured to seal the intermediate space (116) at a second periphery (114) between the process chamber inner wall (110) and the powder-material-supporting plate assembly (112) in the process chamber (410) of the installation (400), the first seal (102) being spaced apart from the second seal (104) such that, when the intermediate space (116) is sealed between the process chamber inner wall (110) and the plate assembly (112) by means of the first seal (102) and the second seal (104), a channel (106) is formed between the first seal (102) and the second seal (104) at an edge of the seal system (110).