Provided is a fusing fluid for the print and fuse manufacture of three-dimensional objects from particulate build material, wherein the fusing fluid comprises or consists of a non-aqueous carrier liquid; a radiation absorber; and optionally a dispersant and/or one or more further additives; wherein the fusing fluid has a boiling range lying within a temperature window of 150 to 350 °C at normal pressure of 101.3 kPa with a boiling range width of less than or equal to 70 °C, wherein the boiling range is defined by a boiling onset temperature Tb_onset and a boiling endset temperature Tb_endset determined according to the method described in the specification, and wherein the boiling range width is Tb_endset minus Tb_onset. Further provided are: a materials kit comprising the fusing fluid and a particulate build material, optionally wherein the particulate build material comprises a flame retardant component; a method and apparatus for the print and fuse manufacture of a three-dimensional object utilizing the materials kit; use of the fusing fluid or of the materials kit in a print and fuse method; and a resulting object having improved flame retardancy.
B29C 64/165 - Procédés de fabrication additive utilisant une combinaison de matériaux solides et liquides, p. ex. une poudre avec liaison sélective par liant liquide, catalyseur, inhibiteur ou absorbeur d’énergie
B33Y 70/00 - Matériaux spécialement adaptés à la fabrication additive
B33Y 70/10 - Composites de différents types de matériaux, p. ex. mélanges de céramiques et de polymères ou mélanges de métaux et de biomatériaux
2.
COMPUTER IMPLEMENTED METHOD FOR POWDER BED FUSION PROCESSES AND APPARATUS
Provided is a computer-implemented method of determining layer anomalies in a powder bed fusion process, wherein a build process to form a three-dimensional object comprises a layer sequence of distributing a layer, preheating the layer, measuring a pre-fuse temperature of the layer, applying fusing energy to the layer, optionally to selectively fuse an object cross section within the layer, measuring a post-fuse temperature of the layer, and repeating the layer sequence for at least a subset of a plurality of layers over which the object is to be formed, the method comprising: obtaining the measured pre-fuse temperatures and the measured post-fuse temperatures for at least the subset of the plurality of layers; providing for each layer an estimated pre-fuse temperature based on a corresponding measured post-fuse temperature; determining a temperature difference between the estimated pre-fuse temperature and the measured pre-fuse temperature for each layer to generate a temperature difference data set; determining a level of deviation from the temperature difference data set; determining a layer anomaly in the powder bed fusion process if the level of deviation exceeds a predefined threshold; and upon determining one or more layer anomalies, causing a user alert to be generated and/or causing the build process to be stopped. A powder bed fusion apparatus comprising a processor configured to carry out the method is also provided.
B22F 10/28 - Fusion sur lit de poudre, p. ex. fusion sélective par laser [FSL] ou fusion par faisceau d’électrons [EBM]
B22F 10/368 - Température ou gradient de température, p. ex. température du bassin de fusion
B22F 12/90 - Moyens de commande ou de régulation des opérations, p. ex. caméras ou capteurs
B29C 64/153 - Procédés de fabrication additive n’utilisant que des matériaux solides utilisant des couches de poudre avec jonction sélective, p. ex. par frittage ou fusion laser sélectif
B29C 64/393 - Acquisition ou traitement de données pour la fabrication additive pour la commande ou la régulation de procédés de fabrication additive
B33Y 40/00 - Opérations ou équipements auxiliaires, p. ex. pour la manipulation de matériau
B33Y 50/02 - Acquisition ou traitement de données pour la fabrication additive pour la commande ou la régulation de procédés de fabrication additive
B22F 10/14 - Formation d’un corps vert par projection de liant sur un lit de poudre
B29C 64/165 - Procédés de fabrication additive utilisant une combinaison de matériaux solides et liquides, p. ex. une poudre avec liaison sélective par liant liquide, catalyseur, inhibiteur ou absorbeur d’énergie
B33Y 30/00 - Appareils pour la fabrication additiveLeurs parties constitutives ou accessoires à cet effet
3.
METHOD FOR GENERATING DATA FOR AN EMBEDDED PATTERN FOR USE IN POWDER BED FUSION
Provided is a method of generating object model data comprising embedded pattern data, to cause an embedded pattern to be applied to a 3D object formed by layerwise fusion of particulate build material, the method comprising: generating object model data in the form of initial slices, wherein each slice defines one or more object pixels to be processed in a corresponding layer to form a cross section of the 3D object, and wherein each object pixel defines an amount of absorber to be deposited over a corresponding object voxel within a respective layer; generating modified object model slices from the initial object model slices to include embedded contrast pattern pixels by: defining at least one ultimate group of object pixels comprised within the object model surface to define corresponding at least one group of encapsulating object voxels, and at least one penultimate group of object pixels overlapping with the ultimate group of pixels, wherein the penultimate group of object pixels comprises at least a first subgroup and second subgroup of object pixels that together define the embedded contrast pattern; and setting the amount of absorber of the first subgroup to at least a first amount of absorber, and setting the amount of absorber of the second subgroup either to zero or to a second amount lower than the first amount. Further provided is a processor configured to carry out the method and an object formed from the object model data generated according to the method.
B29C 64/165 - Procédés de fabrication additive utilisant une combinaison de matériaux solides et liquides, p. ex. une poudre avec liaison sélective par liant liquide, catalyseur, inhibiteur ou absorbeur d’énergie
B22F 10/14 - Formation d’un corps vert par projection de liant sur un lit de poudre
B22F 10/80 - Acquisition ou traitement des données
B29C 64/386 - Acquisition ou traitement de données pour la fabrication additive
A post-processing station (1) for recovering powder build material from a build volume produced by a 3D printer wherein the build volume comprises one or more 3D objects and build material is provided, the post-processing station comprising: a depowdering unit; a vacuum pump (60); a first cyclone (20), having an inlet, an air outlet and a solids outlet, wherein the inlet of the first cyclone is operably in fluidic communication with the depowdering unit and wherein the air outlet of the first cyclone is operably in fluidic communication with the vacuum pump; a sieving unit (30) comprising a sieve (34) in fluidic communication with the solids outlet of the first cyclone, wherein the sieve comprises a first surface to which the solids outlet of the first cyclone delivers build material, and a second surface through which sieved build material passes; a second cyclone (40), having an inlet, an air outlet and a solids outlet, wherein the inlet of the second cyclone is operably in fluidic communication with the first surface of the sieve, and the air outlet of the second cyclone is operably in fluidic communication with the vacuum pump; and a valve (102), located between the sieving unit and the inlet of the second cyclone; wherein during operation of the vacuum pump the post-processing station is configured to operate in a first, depowdering, mode, in which the valve is closed, and in a second, sieve-cleaning, mode, in which the valve is open.
Provided is an apparatus for the layerwise manufacture of 3D objects from particulate build material, wherein the apparatus comprises a distributor to distribute each layer of build material; a first fusing source and a second fusing source, each configured to provide fusing energy based on image slices defining each object cross section to be formed within a corresponding layer, wherein at least one of the first and second fusing sources is configured to provide selective fusing energy to selected object voxels of the layer within the object cross sections; and a controller configured to: control the distributor to distribute a layer; control in either order the first fusing source to fuse selected object voxels to form an object cross section and the second fusing source to further fuse the object voxels fused by the first fusing source; and repeat the distributing, fusing and further fusing to form the object from a sequence of object cross sections. A method of operation of the apparatus is also provided.
B29C 64/153 - Procédés de fabrication additive n’utilisant que des matériaux solides utilisant des couches de poudre avec jonction sélective, p. ex. par frittage ou fusion laser sélectif
B29C 64/165 - Procédés de fabrication additive utilisant une combinaison de matériaux solides et liquides, p. ex. une poudre avec liaison sélective par liant liquide, catalyseur, inhibiteur ou absorbeur d’énergie
Provided is an apparatus for the layerwise manufacture of objects from particulate material, comprising a distribution device to distribute each layer; a digital light projector operable in scrolling mode over the layer and comprising a digital mirror device and a light source, wherein the digital mirror device comprises an array of individually addressable micromirrors each of which is arranged to redirect a light beam received from the light source away from or towards the layer based on image slices, wherein some or all of the image slices comprise a fusing slice defining a fusing energy level for each of a plurality of object voxels to be fused to form an object cross section within the layer; and a controller configured to: control the distribution device to distribute the layer; and control the digital light projector to scroll redirected light beams across the layer while controlling each micromirror to selectively direct fusing energy beams towards each object voxel within the object cross section based on modifying each fusing slice by a fusing mask; wherein the fusing mask is associated with the reference frame of the micromirror array and defines modification data for each micromirror to modify the initial energy level of each fusing slice, such that each object voxel is provided with a predefined fusing intensity profile over an irradiation duration. A method of providing energy beam control data for the digital mirror device in form of modified fusing slices is also provided.
B29C 64/153 - Procédés de fabrication additive n’utilisant que des matériaux solides utilisant des couches de poudre avec jonction sélective, p. ex. par frittage ou fusion laser sélectif
B22F 10/28 - Fusion sur lit de poudre, p. ex. fusion sélective par laser [FSL] ou fusion par faisceau d’électrons [EBM]
B22F 12/47 - Moyens de rayonnement avec mouvement de translation parallèle au plan de dépôt
B29C 64/277 - Agencements pour irradiation utilisant des moyens de rayonnement multiples, p. ex. des micro-miroirs ou des diodes électroluminescentes multiples [LED]
B29C 64/393 - Acquisition ou traitement de données pour la fabrication additive pour la commande ou la régulation de procédés de fabrication additive
Provided is an apparatus (10) for the layerwise manufacture of 3D objects from particulate build material, the apparatus comprising a distribution device (290) to distribute each layer (160); a digital light projector comprising a digital mirror device (240) and a light source (250), wherein the digital mirror device comprises an array of individually addressable micromirrors, each arranged to redirect an energy beam incident on the array from the light source towards the layer to heat corresponding voxels of the layer; and a controller arranged to: control the distribution device (290) to distribute a layer (160); control each micromirror to selectively provide non-fusing energy beams (420H,4220L) of different non-fusing energies to the layer to heat corresponding voxels to a predefined temperature below the melting temperature; to repeat the distributing and heating to form a plurality of layers; and for at least one of the plurality of layers, to control a fusing energy beam source to provide fusing energy (410) to voxels within the object cross section of said at least one layer so as form a 3D object. A method for operating the apparatus is also provided.
B29C 64/153 - Procédés de fabrication additive n’utilisant que des matériaux solides utilisant des couches de poudre avec jonction sélective, p. ex. par frittage ou fusion laser sélectif
B22F 10/28 - Fusion sur lit de poudre, p. ex. fusion sélective par laser [FSL] ou fusion par faisceau d’électrons [EBM]
B22F 10/362 - Commande ou régulation des opérations des paramètres du faisceau d’énergie pour le préchauffage
B22F 10/368 - Température ou gradient de température, p. ex. température du bassin de fusion
B22F 10/85 - Acquisition ou traitement des données pour la commande ou la régulation de procédés de fabrication additive
B22F 12/13 - Moyens de chauffage auxiliaires pour préchauffer le matériau
B22F 12/44 - Moyens de rayonnement caractérisés par la configuration des moyens de rayonnement
B22F 12/90 - Moyens de commande ou de régulation des opérations, p. ex. caméras ou capteurs
B29C 64/277 - Agencements pour irradiation utilisant des moyens de rayonnement multiples, p. ex. des micro-miroirs ou des diodes électroluminescentes multiples [LED]
B29C 64/30 - Opérations ou équipements auxiliaires
B29C 64/393 - Acquisition ou traitement de données pour la fabrication additive pour la commande ou la régulation de procédés de fabrication additive
Provided is an apparatus (1) for the formation of 3D objects by additive manufacturing, the apparatus comprising: a process chamber (10) within which the 3D objects are formed during use, wherein, during object formation, the process chamber (10) comprises gas at a temperature higher than gas in an environment external to the process chamber; a gas extraction duct (20) configured to guide gas out of the process chamber; and a controller; wherein the gas extraction duct (20) comprises: a main duct (22) having an extraction opening (228) connectable to an extraction source (80) and an inflow opening (222) configured to draw in gas from an external environment exterior; a secondary duct (24) having an inlet opening (224) connected to a process chamber outlet (120) and an outlet opening (226) coupled to the main duct (22) between the extraction opening and the inflow opening; and one or more temperature sensors (310) thermally coupled to the interior of the gas extraction duct (20), and arranged to measure temperature of gas flow at one or more locations within the gas extraction duct; the one or more temperature sensors (310) comprising at least one of: an extraction temperature sensor (310) arranged at a location at, or between, the extraction opening of the main duct and the outlet opening of the secondary duct; and an inflow temperature sensor (340) arranged at or adjacent the inflow opening of the main duct, and a heater (410) arranged to provide a baseline temperature to the inflow temperature sensor; wherein, in use, the controller (70) is configured to determine, based on the temperature measurements, whether a gas flow rate applied by the extraction source is within a predefined range. Further provided is a method of determining gas extraction flow rate based on temperature measurements using the apparatus.
B29C 64/135 - Procédés de fabrication additive n’utilisant que des matériaux liquides ou visqueux, p. ex. dépôt d’un cordon continu de matériau visqueux utilisant des couches de liquide à solidification sélective caractérisés par la source d'énergie à cet effet, p. ex. par irradiation globale combinée avec un masque la source d’énergie étant concentrée, p. ex. lasers à balayage ou sources lumineuses focalisées
B22F 10/28 - Fusion sur lit de poudre, p. ex. fusion sélective par laser [FSL] ou fusion par faisceau d’électrons [EBM]
B22F 10/322 - Commande ou régulation des opérations de l’atmosphère, p. ex. de la composition ou de la pression dans une chambre de fabrication d’un écoulement de gaz, p. ex. du débit ou de la direction
B22F 12/17 - Moyens de chauffage auxiliaires pour chauffer la chambre ou la plate-forme de formation
B22F 12/90 - Moyens de commande ou de régulation des opérations, p. ex. caméras ou capteurs
B29C 64/153 - Procédés de fabrication additive n’utilisant que des matériaux solides utilisant des couches de poudre avec jonction sélective, p. ex. par frittage ou fusion laser sélectif
Provided is a method for dimensional compensation of a 3D object to be formed by an apparatus for the layerwise manufacture of 3D objects from build material, the method comprising: receiving an object model to form a corresponding object in an apparatus for the layerwise manufacture of objects; positioning the object model in a virtual build volume representing an actual build volume of the apparatus in which the object is to be formed; determining a reference point for the object model, the reference point determining an object model location within the virtual build volume for the object model; selecting, from a scaling factor map comprising a plurality of predetermined scaling factors, a scaling factor corresponding to the object model location, each scaling factor corresponding to one or more of a plurality of locations within the virtual build volume; and applying the scaling factor to the object model. Further provided is a controller configured to carry out the method.
Provided is a post processing station for recovering unfused build material from a build volume produced by a 3D printer, the build volume comprising 3D objects and unfused material, the post processing station being configured to receive a build container comprising a build volume and an electronic tag, the electronic tag storing at least one of a build material ID, and a source ID and a post processing station ID, or a link to at least one of said IDs stored on a data storage device; wherein the post processing station comprises a controller having an electronic tag reader in communication with a validation data storage device, the validation data storage device comprising one or more stored allowable build material IDs and/or one or more stored allowable source IDs; wherein the controller is configured to read the tag and thereby obtain the build material ID and/or source ID; determine whether the said one or more obtained IDs corresponds to an allowable ID by comparing the obtained IDs with the stored allowable IDs; and upon determining that the obtained build material ID and/or the obtained source ID corresponds to one of said allowable IDs, accept the unfused build material for dosing, or upon determining that the obtained build material ID and/or the obtained source ID does not correspond to an allowable ID, generate an alert that the obtained build material ID and/or the obtained source ID cannot be verified. Further provided is an additive manufacturing system comprising such a post processing station and one or more 3D printers, and a method of controlling the flow of build material through the post processing station and the system.
Provided is a build material supply system for an apparatus for the layerwise manufacture of 3D objects, the build material supply system comprising a dosing device configured to supply a dosed amount of build material to a work surface of the apparatus, the dosed amount comprising a layer amount and an excess amount; a buffer tank configured to mix build material for supplying to the dosing device; an excess return chamber for receiving excess build material from a distribution device; a supply tank for holding fresh build material; a first pump and a second pump; and a controller; wherein: the first pump is coupled to the supply tank via a first valve and to the excess return chamber; the first pump is coupled to an inlet of the buffer tank; the second pump is coupled to the buffer tank and to the dosing device; the controller is coupled to the first and second pump and the first valve; wherein to control the amount of fresh build material compared to the excess amount of build material transported into the buffer tank, the controller is configured to: control the first valve to be open, and the first pump to operate, to allow build material to flow along a supply flow path from the supply tank through the first pump and into the buffer tank; and to allow build material to flow along an excess return flow path from the excess return chamber through the first pump and into the buffer tank; control the first valve to close, the first pump to stop operating, and the second pump to operate to allow build material to flow along a dosing flow path from the buffer tank through the second pump and into the dosing device. A method of transporting build material through the build material systems is also provided.
Provided are build material supply systems for apparatus for the layerwise manufacture of 3D objects, comprising a dosing device to supply a dosed amount of build material, comprising a layer and an excess amount, to a work surface; a buffer tank to mix build material; an excess return chamber to receive excess build material; a supply tank for fresh build material; a build material pump; and a controller; wherein an inlet of the build material pump is coupled to the supply tank via a first valve, and, in a first embodiment: the inlet of the build material pump is coupled to the excess return chamber via a second valve, and to the buffer tank via a third valve; an outlet of the pump is coupled to the buffer tank via a fourth valve and to an inlet of the dosing device via a fifth valve; wherein the controller is coupled to the pump and to the said valves and is configured to (i) control the first, second and fourth valves to close, the third and fifth valves to open, and the pump to operate, to allow build material to flow from the buffer tank to the dosing device; (ii) control the third and fifth valves to close, the first valve and fourth valves to open, and the pump to operate to allow fresh build material to flow from the supply tank into the buffer tank; and (iii) control the third and fifth valves to close, the second and fourth valves to open, and the pump to operate, so as to allow excess build material to flow from the excess return chamber into the buffer tank; and in a second embodiment: the inlet of the build material pump is coupled an outlet of the excess return chamber; an outlet of the pump is coupled to an inlet of the buffer tank; and an outlet of the buffer tank is coupled to an inlet of the dosing device; wherein the controller is coupled to the pump and the first valve and is configured to control the first valve to open and the pump to operate to allow fresh build material to flow from the supply tank into the buffer tank and to allow excess build material to flow from the excess return chamber into the buffer tank. A method of transporting build material through the build material systems is also provided.
B29C 64/153 - Procédés de fabrication additive n’utilisant que des matériaux solides utilisant des couches de poudre avec jonction sélective, p. ex. par frittage ou fusion laser sélectif
B22F 10/28 - Fusion sur lit de poudre, p. ex. fusion sélective par laser [FSL] ou fusion par faisceau d’électrons [EBM]
B29C 64/165 - Procédés de fabrication additive utilisant une combinaison de matériaux solides et liquides, p. ex. une poudre avec liaison sélective par liant liquide, catalyseur, inhibiteur ou absorbeur d’énergie
Provided is a method for generating formation data for a plurality of object model repeat units for the layerwise formation of object repeat units based on the formation data (500), the method comprising: (a) providing a plurality of virtual build volume slices stacked in the layering direction of a corresponding object formation process and based on a thickness of layers of the object repeat units to be formed (520); (b) slicing the object model repeat unit to form a repeat unit slice stack of repeat unit slices, the repeat unit slices being of same thickness in the layering direction as the virtual build volume slices (510); (c) defining a position and orientation for each of a plurality of the repeat unit slice stacks over a number of base slices of the virtual build volume (530); and (d) generating a base slice stack by placing each of the plurality of the repeat unit slice stacks according to the defined position and orientation within the base slice stack (540). An object formed according to the method and a processor configured to carry out the method are also provided.
Provided is an apparatus for the layerwise manufacture of one or more 3D objects from particulate build material, wherein the apparatus comprises a build area (12) within a work surface (8) and over which the one or more 3D objects are to be formed, wherein the build area (12) represents the surface of the topmost layer, the apparatus comprising: a dosing device (60) configured to provide an amount of build material to the work surface (8); a roller (32) configured to pass over the build area (12) while rotating about an axis of rotation to distribute the dosed amount of the build material over the build area (12) to form a layer, the axis of rotation being perpendicular to the direction of distribution; and a cleaning device (34) comprising a cleaning portion extending parallel to the axis of rotation, wherein the cleaning device (34) comprises a plurality of perforations (P) comprised at least within the cleaning portion, the perforations (P) extending from a cleaning surface (46) of the cleaning portion to an opposite surface of the cleaning portion opposite the cleaning surface (46); wherein the cleaning surface (46) is configured to at least intermittently engage against the roller (32) surface while the roller (32) rotates, and wherein the perforations (P) are configured to allow build material to pass from the roller (32) through the cleaning portion to the opposite surface while the cleaning surface (46) is in engagement with the roller (32) surface. A method of operation is also provided.
Provided is a method of operation for an apparatus for the layerwise manufacture of 3D objects from particulate material, the apparatus comprising a build area arranged between a dosing device side and a receiving chamber side, a dosing device at the dosing device side configured to dose an amount of build material onto a work surface comprising the build area, and a receiving chamber configured to receive at least a portion of the dosed amount and to return the portion to the dosing device; wherein the method comprises a warm up phase followed by a build phase for one or more 3D objects, the warm up phase and the build phase comprising a cycle of the steps of (a) dosing the amount of build material from the dosing device onto the work surface; (b) pushing at least a portion of the dosed amount across the build area from a dosing device side to a receiving chamber side of the build area and into the receiving chamber; (c) heating the dosed amount at one or both of steps (a) and (b); wherein the steps (a) to (c) are repeated until each phase is complete; wherein the build phase further comprises at step (b): forming a layer over the build area from a layer portion of the dosed amount while pushing the dosed amount over the build area, and at step (c) a step of selectively melting the build material within a layer-specific region defined within the build area; wherein, over a given duration of time, an aggregate volume of the portions of build material pushed into the receiving chamber during the warm up phase is larger than an aggregate volume of the portions of build material pushed into the receiving chamber during the build phase. A controller configured to determine one or more properties of the warm up phase based on a predefined duration over which the warm up phase is to be applied to achieve a steady thermal state is also provided. 30
B29C 64/153 - Procédés de fabrication additive n’utilisant que des matériaux solides utilisant des couches de poudre avec jonction sélective, p. ex. par frittage ou fusion laser sélectif
B22F 10/28 - Fusion sur lit de poudre, p. ex. fusion sélective par laser [FSL] ou fusion par faisceau d’électrons [EBM]
B22F 10/85 - Acquisition ou traitement des données pour la commande ou la régulation de procédés de fabrication additive
B22F 12/13 - Moyens de chauffage auxiliaires pour préchauffer le matériau
B22F 12/00 - Appareils ou dispositifs spécialement adaptés à la fabrication additiveMoyens auxiliaires pour la fabrication additiveCombinaisons d’appareils ou de dispositifs pour la fabrication additive avec d’autres appareils ou dispositifs de traitement ou de fabrication
Provided is a method of operation for an apparatus for the layerwise manufacture of 3D objects from particulate build material, wherein the apparatus comprises a build area comprised within a work surface and one or more heat sources configured to heat build material; the method comprises two or more operational cycles of a warm up phase. The first operational cycle starts from an ambient thermal state, followed by a build phase to manufacture one or more objects, followed by a cooling phase, wherein the cooling phase comprises removing a plurality of warm up layers and build layers from the apparatus. Before progressing to the build phase, a target steady thermal state is achieved over the plurality of warm up layers as determined from a measured thermal state; the target steady thermal state is maintained over the plurality of build layers; the target steady thermal state is exited to commence the cooling phase over which a reduced thermal state is achieved, wherein the reduced thermal state is above the ambient thermal state. One or more properties of the further warm up phase are determined based on the reduced thermal state of the preceding cooling phase, such that a duration of the further warm up phase is shorter than a duration of the warm up phase of a preceding operational cycle.
B29C 64/165 - Procédés de fabrication additive utilisant une combinaison de matériaux solides et liquides, p. ex. une poudre avec liaison sélective par liant liquide, catalyseur, inhibiteur ou absorbeur d’énergie
B29C 64/291 - Agencements pour irradiation pour un fonctionnement dans un ensemble, p. ex. avec des activateurs ou des inhibiteurs sélectivement appliqués
Provided is a method for preparing virtual build volumes comprising three-dimensional object models for an apparatus for the manufacture of three-dimensional objects, wherein the virtual build volume represents an actual build volume over which the one or more objects are to be built. The method comprising the steps of: (a) receiving one or more object models, the object models defining the intended dimensions of each of the one or more objects; (b) applying a transformation to an initial virtual build volume so as to create a reduced virtual build volume smaller in volume than the virtual build volume; (c) positioning the one or more object models within the reduced virtual build volume; and (d) applying an inverse transformation to expand the reduced virtual build volume comprising the one or more object models to create an expanded virtual build volume comprising one or more expanded object models; wherein each of the one or more expanded object models is larger than the respective one or more object models. Further provided are a processor and a computer program for carrying out the method.
A method is provided for layer-by-layer manufacturing of a three- dimensional object from a powder, wherein a droplet deposition unit (38), a first radiation source (LI), a powder distributor (36) and a second radiation source (L2) are moveably provided over a working surface (13), the working surface (13) comprising a build area (12) on which the object is formed layer-by-layer, the method comprising, in a first direction across a plurality of locations (PI, P2) on the build area (12): moving the droplet deposition unit (38) and depositing, using a droplet deposition unit (38), a radiation absorber onto regions of a previously applied layer of powder distributed across a build area (12) moving the first radiation source (LI) according to a first velocity profile whilst activating the first radiation source (LI) to apply fusing energy to the build area (12) to fuse the regions of powder where the absorber has been deposited; moving the powder distributor (36) according to a second velocity profile and distributing a fresh layer of powder over the build area (12); and moving the second radiation source (L2) whilst activating the second radiation source (L2) to apply energy to preheat the fresh layer of powder; wherein the method further comprises adjusting the first and/or second velocity profiles to control a time interval At between the passing of the first radiation source (LI) and the powder distributor (38) at each of the plurality of locations (PI, P2). A controller (200) configured to receive instructions from a data store to carry out the method, and an apparatus for the layer-by-layer manufacture of a three-dimensional object using the method are also provided.
B29C 64/165 - Procédés de fabrication additive utilisant une combinaison de matériaux solides et liquides, p. ex. une poudre avec liaison sélective par liant liquide, catalyseur, inhibiteur ou absorbeur d’énergie
B29C 64/236 - Moyens d’entraînement pour un mouvement dans une direction dans le plan d’une couche
brevets
