A gas turbine combustion chamber, having a combustion chamber housing, a burner positioned at least partially in the combustion chamber housing and a flame tube positioned in the combustion chamber housing. An upstream end of the flame tube has a flame tube cover. In the region of the flame tube cover radially inside the flame tube cover a mixing tube of the burner extends, which defines a pre-primary combustion zone. Between the mixing tube of the burner and the flame tube cover an axial air flow passage is formed, via which air can be conducted in the axial direction outside along the mixing tube, and into the flame tube cover radial air flow passages are introduced via which the air following the axial air flow passage can be conducted in the radial direction of the flame tube cover for cooling the flame tube cover.

One aspect is a method of fabricating a housing for an implantable medical device, including forming a first housing portion of metal using an additive manufacturing process such that features are integrated into the first portion. A second housing portion of metal is also formed. The first and second housing portions are joining thereby sealing an internal space of the housing within first and second portions and fully containing the features such that they are hermetically sealed relative to an external space outside the housing.

The manufacturing rate of selective production methods is increased by using thicker powder layers.

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.

An exposure control device (31) serves for equipping and/or retrofitting a generative layer-wise building device (1). The latter comprises an exposure device (20) which emits electromagnetic radiation (22) or particle radiation and is configured to irradiate positions to be solidified in a layer in such a way that after cooling they exist as an object cross-section or part of the same. The exposure control device (31) has a first data output interface (36), at which control commands can be output to the exposure device (20). The control commands which are output specify one of a plurality of exposure types wherein an exposure type is defined by a predetermined combination of a radiation energy density to be emitted by the exposure device (20) and a scanning pattern with which the radiation (22) is being directed to a region of a layer of the building material (15). Furthermore, the exposure control device (31) has a second data output interface (37) at which an exposure type can be output in real time in relation to a timing of the output of a control command specifying this exposure type.

The present disclosure provides three-dimensional (3D) printing processes, apparatuses, software, and systems for the production of at least one desired 3D object. The 3D printer system (e.g., comprising a processing chamber, build module, or an unpacking station) described herein may retain a desired (e.g., inert) atmosphere around the material bed and/or 3D object at multiple 3D printing stages. The 3D printer described herein comprises one or more build modules that may have a controller separate from the controller of the processing chamber. The 3D printer described herein comprises a platform that may be automatically constructed. The invention(s) described herein may allow the 3D printing process to occur for a long time without operator intervention and/or down time.

A recoating unit (40) serves for equipping or retrofitting a device (1) for additive manufacturing of a three-dimensional object (2) by selectively solidifying a building material (15), preferably a powder, layer by layer. The device (1) comprises a recoater (16) movable across a build area (8) for applying a layer (31b, 32b) of the building material (15) within the build area (8) and a solidification device (20) for selectively solidifying the applied layer (31b, 32b) at positions corresponding to a cross-section of the object (2) to be manufactured. The device (1) is formed and/or controlled to repeat the steps of applying and selectively solidifying until the object (2) is completed. The recoating unit (40) comprises at least two recoating rollers (41, 42) spaced apart from each other in a first direction (B1) and extending into a second direction transversely, preferably perpendicularly, to the first direction, and a compacting and/or smoothing element (45) arranged between the two recoating rollers (41, 42) in the first direction (B1) and extending into the second direction. The recoating unit (40) is adapted to draw-out building material to a regular layer (31a, 32a), depending on the movement of the recoating unit into the first direction (B1) or into its reverse direction (B2), using the recoating roller (41, 42) arranged ahead in the respective moving direction (B1, B2), and to compact or smoothen the layer (31a, 32a) drawn-out by the recoating roller (41, 42) arranged ahead using the compacting and/or smoothing element (45).

A recoating unit (40) serves for equipping or retrofitting a device (1) for additive manufacturing of a three-dimensional object (2) by selectively solidifying a building material (15), preferably a powder, layer by layer. The device (1) comprises a recoater (16) movable across a build area (8) for applying a layer (31b, 32b) of the building material (15) within the build area (8) and a solidification device (20) for selectively solidifying the applied layer (31b, 32b) at positions corresponding to a cross-section of the object (2) to be manufactured. The device (1) is formed and/or controlled to repeat the steps of applying and selectively solidifying until the object (2) is completed. The recoating unit (40) comprises at least two recoating rollers (41, 42) spaced apart from each other in a first direction (B1) and extending into a second direction transversely, preferably perpendicularly, to the first direction. At least one of the recoating rollers (41, 42), preferably both of the recoating rollers (41, 42) are formed adjustable in a third direction perpendicular to the first direction and the second direction in the recoating unit (40).

A method of metallurgical processing includes, providing a workpiece that has been formed by additive manufacturing of a nickel-chromium based superalloy. The workpiece has an internal porosity and a microstructure with a columnar grain structure and delta phase. The workpiece is then hot isostatically pressed to reduce the internal porosity and to at least partially retain the columnar grain structure and the delta phase. The workpiece is then heat treated to at least partially retain the columnar grain structure and the delta phase.

The present disclosure generally relates to methods for additive manufacturing (AM) for fabricating multi-walled structures. A multi-walled structure includes a first wall having a first surface and a second wall having a second surface facing the first surface to define a passage having a width between the first surface and the second surface in a first direction. The multi-walled structure also includes an enlarged powder removal feature connecting the first wall and the second wall. The enlarged powder removal feature has an inner dimension greater than the width in the first direction and at least one open end in a direction transverse to the first width.