Abstract: A method of operating an apparatus for the layerwise manufacture of 3D objects. The method includes two or more operational cycles of a warm up phase, starting from ambient, followed by a build phase and a cooling phase. The warm up phase and the build phase each include a layer cycle of: (a) dosing build material to the work surface; (b) distributing a portion of the dosed amount over a build area; (c) heating the dosed amount; and (d) monitoring a temperature of the build material to determine a thermal state. The build phase includes melting layer-specific regions. These steps are repeated until the warm up and build phases are completed. A property of the subsequent warm up phases is determined such that the duration of a subsequent warm up phase is shorter than the duration of a preceding warm up phase.

Abstract: Provided is a method for the layer-by-layer manufacture of an object from particulate material, the method comprising the steps of: (a) distributing a layer of particulate material over a build bed, the layer forming a build bed surface and having a layer thickness; (b) preheating the layer to a preheat temperature; (c) heating a cross section of the object of the layer to at least a sintering temperature to cause the particulate material of the cross section to sinter or melt; (d) lowering the build bed by an increment; and (e) distributing a further layer of particulate material of substantially an intended layer thickness, the further layer forming the build bed surface; wherein an object layer cycle comprises the steps (b) to (d); and (f) optionally, repeating the object layer cycle until the object is complete; wherein the increment is different to the intended layer thickness. Further provided is a controller for carrying out the method and an apparatus comprising the controller.

Abstract: Apparatus (1) for manufacturing a three-dimensional object from a powder, the apparatus comprising: a work surface (170); a build bed (201) having a build area (190), the build area (190) being comprised within the work surface (170), wherein successive layers of said three-dimensional object are formed in the build bed (201); a first powder supply module (2) fixedly arranged on a first side of the work surface (170), outward from a first side of the build bed (201); a second powder supply module (3) fixedly arranged on a second side of the work surface (170), outward from a second side of the build bed (201); a first powder distribution sled (300) operable to distribute powder dosed to the work surface (170) from the first powder supply module (2) while moving in a first direction from the first side of the work surface (170) towards the second side of the work surface (170), and from the second powder supply module (3) while moving in a second direction from the second side of the work surface (170) towards

Abstract: A method for the manufacture of three-dimensional objects is disclosed, utilising an independently operable printing sled (350) for sintering fusible powder and an independently operable powder distribution sled (300) for depositing a layer of fusible powder on the sintered layer. Since the printing sled and the powder distribution sled are independently operable, the time between sintering and deposition can be altered, dependent on the printing conditions and materials, resulting in an enhanced bond between the layers of the three-dimensional object.