In one example, an apparatus includes a carriage to carry a payload through a manufacturing space at the urging of control elements in a control space and a belt movable with the carriage to block contaminants in the manufacturing space from passing to the control space along a carriage travel path.

A 3D printer to additively manufacture a 3D object includes a coater, a dispenser, and an energy source. The coater is to coat a first material relative to a print bed to form a selectable number of first layers. The dispenser is to dispense a first fluid agent onto first selected locations of the first layers of the first material. The energy source is to cause fusing at the first selected locations. The dispenser is to also dispense a second fluid agent including a second material to form a selectable number of second layers of the second material at second selected locations on top of the selectable number of first layers. Each second selected location comprises at least some of the fused first selected locations.

A 3D printer to additively manufacture a 3D object includes a coater, a dispenser, and an energy source. The coater is to coat a first material relative to a print bed to form a selectable number of first layers. The dispenser is to dispense a first fluid agent onto first selected locations of the first layers of the first material. The energy source is to cause fusing at the first selected locations. The dispenser is to also dispense a second fluid agent including a second material to form a selectable number of second layers of the second material at second selected locations on top of the selectable number of first layers. Each second selected location comprises at least some of the fused first selected locations.

In an example, an apparatus includes processing circuitry comprising a model assessment module to identify an indication of a conductive element within object model data representing an object to be printed and a print instruction module to generate print instructions to generate the object. The print instructions may include an instruction to print conductive agent to form the conductive element and an instruction to print a fusing agent comprising an instruction to reduce an amount of fusing agent to be printed in a region of the conductive element compared to at least one other region of the object.

In an example, an apparatus includes processing circuitry comprising a model assessment module to identify an indication of a conductive element within object model data representing an object to be printed and a print instruction module to generate print instructions to generate the object. The print instructions may include an instruction to print conductive agent to form the conductive element and an instruction to print a fusing agent comprising an instruction to reduce an amount of fusing agent to be printed in a region of the conductive element compared to at least one other region of the object.

A method, apparatus, and program for additive manufacturing. In one aspect, the method and program comprises forming an at least partially solidified portion within a first scan region by irradiating a build material at a first energy density value along a first irradiation path. A second at least partially solidified portion is formed within a second scan region that is spaced with respect to the first scan region, wherein the solidified portion within the first scan region is formed by irradiation a build material at a second energy density value along a second irradiation path. The space between the first scan region and the second scan region is at least partially solidified by irradiating a build material at a third energy density value that less than the first energy density value and the second energy density value.

In one example, an apparatus includes a carriage to carry a payload through a manufacturing space at the urging of control elements in a control space and a belt movable with the carriage to block contaminants in the manufacturing space from passing to the control space along a carriage travel path.

In one example, an apparatus includes a carriage to carry a payload through a manufacturing space at the urging of control elements in a control space and a belt movable with the carriage to block contaminants in the manufacturing space from passing to the control space along a carriage travel path.

The present disclosure generally relates to methods and apparatuses for laser shock peening during additive manufacturing (AM) processes. Such methods and apparatuses can be used to embed microstructural and/or physical signatures into manufactured objects, and such embedded chemical signatures may find use in anti-counterfeiting operations and in manufacture of objects with multiple materials.

A method of manufacturing a structural component having tailored material properties by applying an IR-absorbent coating to a substrate formed of a ferrous-based, aluminum-based, magnesium-based, or fiber reinforced composite material is provided. The coating is preferably formed of iron oxide (Fe.sub.3O.sub.4) decorated multiwall carbon nanotubes. Alternatively, the coating is wax-based or polymer-based and includes TriSilanollsooctylt POSS and additives. Different coating compositions may be applied to different zones of the substrate so that the emissivity coefficient varies along the substrate. The coated substrate is heated and formed between a pair of dies to achieve a complex shape or features. The IR-absorbent coating increases the infrared absorption rate during the heating step, which improves formability of the substrate. The iron oxide (Fe.sub.3O.sub.4) decorated multiwall carbon nanotubes can also be applied to an engine component to increase the thermal efficiency of the engine by reducing friction and enabling the use of light weight materials.