Abstract: A three-dimensional printing kit can include a build material with from about 80 wt % to 100 wt % polymeric particles having a D50 particle size from about 10 ?m to about 150 ?m, and a fusing agent including from about 0.5 wt % to about 20 wt % avobenzone particles dispersed in an aqueous liquid vehicle based on a total weight of the fusing agent.

Abstract: Described herein are methods and systems for printing a three-dimensional object. In an example, a method for printing a three-dimensional object can comprise: (i) a metallic build material being applied; (ii) a binder fluid being applied on at least a portion of the metallic build material; (iii) the selectively applied binder fluid can be flash fused to bind the metallic build material and the selectively applied binder fluid by application of an energy flux having an energy density of from about 0.5 J/cm2 to about 20 J/cm2 for less than about 1 second. In the example, (i), (ii), and (iii) can be repeated at least one time to form the three-dimensional object.

Abstract: A powder bed material can include from 80 wt % to 100 wt % metal particles having a D50 particle size distribution value from 4 ?m to 150 ?m. From 10 wt % to 100 wt % of the metal particles can be surface-activated metal particles having in intact inner volume and an outer volume with structural defects. The structural defects can exhibit an average surface grain density of 50,000 to 5,000,000 per mm2.

Abstract: In an example of a method for three-dimensional (3D) printing, one or more dispersions is/are sprayed to form a layer including build material particles and a liquid agent. The liquid agent is evaporated from the layer to form a build material layer, and based on a 3D object model, a binder agent is applied on at least a portion of the build material layer.

Abstract: Described herein are methods and systems for printing a three-dimensional object. In an example, a method for printing a three-dimensional object can comprise: (i) a metallic build material being applied; (ii) a binder fluid being applied on at least a portion of the metallic build material; (iii) the selectively applied binder fluid can be flash fused to bind the metallic build material and the selectively applied binder fluid by application of an energy flux having an energy density of from about 0.5 J/cm2 to about 20 J/cm2 for less than about 1 second. In the example, (i), (ii), and (iii) can be repeated at least one time to form the three-dimensional object. The binder fluid can comprise a liquid vehicle and polymer particles dispersed in the liquid vehicle.

Abstract: An example of a kit for three-dimensional (3D) printing includes an ultraviolet (UV) light fusing agent. The ultraviolet (UV) light fusing agent includes an aqueous vehicle; and a functionalized benzophenone that is at least partially soluble in the aqueous vehicle, the functionalized benzophenone having absorption at wavelengths ranging from about 340 nm to about 405 nm.

Abstract: A powder bed material can include from 80 wt % to 100 wt % metal particles having a D50 particle size distribution value from 4 ?m to 150 ?m. From 10 wt % to 100 wt % of the metal particles can be surface-activated metal particles having in intact inner volume and an outer volume with structural defects. The structural defects can exhibit an average surface grain density of 50,000 to 5,000,000 per mm2.

Abstract: According to examples, an apparatus includes a processor and a memory on which is stored machine readable instructions. The instructions may cause the processor to identify an intended surface property level for a surface of a three-dimensional (3D) object, determine an amount of radiation to be applied as a flash of radiation onto the surface to obtain the intended surface property level, and output the determined amount of radiation to be applied as a flash of radiation, in which a radiation source is to flash apply the determined amount of radiation onto the surface of the 3D object.

Abstract: An additive manufacturing method includes: selecting one of a plurality of irradiation modules based on a selected module having a wavelength band tuned for absorption by a fusing agent to be used to form an object by additive manufacture; plugging the selected module into a socket over the build platform; supporting successive, stacked layers of the object being formed on the build platform; using a liquid dispenser mounted on the carriage, selectively dispensing the fusing agent into an uppermost layer of build material in a pattern corresponding to a layer of the object being formed; and fusing the build material by exposing the fusing agent to a first wavelength band from a first irradiation source in the selected module.

Abstract: An example of a kit for three-dimensional (3D) printing includes an ultraviolet (UV) light fusing agent. The ultraviolet (UV) light fusing agent includes an aqueous vehicle and a B vitamin or a B vitamin derivative present in an amount that dissolves in the aqueous vehicle. The aqueous vehicle includes a co-solvent, a surfactant, and water. The B vitamin or the B vitamin derivative has absorption at wavelengths ranging from about 340 nm to about 415 nm.

Abstract: An example of a kit for three-dimensional (3D) printing includes an ultraviolet (UV) light fusing agent and a detailing agent. The UV light fusing agent including an aqueous vehicle and a plasmonic metal nanoparticle that i) provides absorption enhancement at radiation wavelengths ranging from about 340 nm to about 450 nm, and ii) is present in an amount up to 2 wt% based on a total weight of the UV light fusing agent. The detailing agent includes a surfactant, a co-solvent, and water.

Abstract: A three-dimensional printing kit can include a build material and a fusing agent. The build material can include from about 80 wt % to 100 wt % polymeric particles having a D50 particle size from about 10 ?m to about 150 ?m. The fusing agent can include an aqueous liquid vehicle and natural food-derived fusing compound dissolved or dispersed therein. The natural food-derived fusing compound can have an absorption peak from about 340 nm to about 780 nm.

Abstract: A three-dimensional (3D) printing method includes applying a build material composition having a polymer particle and a radiation absorbing additive mixed with the polymer particle, the radiation absorbing additive being selected from the group consisting of inorganic near-infrared absorbers, organic near-infrared absorbers, and combinations thereof. The build material composition is preheated to a temperature below the melting temperature of the polymer particle by exposing the build material composition to radiation, the radiation absorbing additive increasing radiation absorption and accelerating the pre-heating of the build material composition. A fusing agent is selectively applied on at least a portion of the build material composition. The method further includes exposing the build material composition to radiation, whereby at least the polymer particle in the at least the portion of the build material composition in contact with the fusing agent at least partially fuses.

Abstract: In an example of a method for three-dimensional (3D) printing, one or more dispersions is/are sprayed to form a layer including build material particles and a liquid agent. The liquid agent is evaporated from the layer to form a build material layer, and based on a 3D object model, a binder agent is applied on at least a portion of the build material layer.

Abstract: An example of an ultraviolet (UV) light fusing agent for three-dimensional (3D) printing includes a UV light absorber and a liquid vehicle. The UV light absorber consists of a fluorescent yellow dye. The liquid vehicle includes a surfactant, a co-solvent, and a balance of water. The UV light fusing agent is devoid of a saccharide.

Abstract: The present disclosure is drawn to a three-dimensional printing system can include a powder bed material, including from 80 wt % to 100 wt % metal particles having a D50 particle size distribution value ranging from 5 ?m to 75 ?m and a powder bed support substrate for receiving the powder bed material. The system can also include a fluid ejector operable to digitally deposit a thermally sensitive binder fluid onto a selected portion of the powder bed material on the powder bed support substrate. The thermally sensitive binder fluid can include water, a reducible metal compound, and a thermally activated reducing agent. A light source can also be present to generate a pulse energy sufficient to cause the thermally activated reducing agent to reduce the reducible metal compound and bind metal particles together to form a green three-dimensional part.

Abstract: A system may include a printhead for ejecting a first fluid including a polymer, the ejected first fluid forming a substrate with a thermal conductivity of less than 0.5 W/(m-K); a spreader to spread a layer of metal particulate on the substrate, wherein the printhead further ejects a second fluid, the ejected second fluid masking a portion of the layer of metal particulate on the substrate; and a pulse irradiation light source to fuse an unmasked portion of the layer of metal particulate.

Abstract: In an example of a three-dimensional (3D) printing method, a metallic build material is applied. A patterning fluid, including a metal salt, is selectively applied on at least a portion of the metallic build material. Prior to an application of additional build material, the metallic build material is exposed to light irradiation to cause the metal salt to reach a thermal decomposition temperature and thermally decompose to a metal. During the exposing, the metallic build material is maintained below a sintering temperature of the metallic build material.

Abstract: In one example in accordance with the present disclosure, an additive manufacturing system is described. The additive manufacturing system includes a build material distributor to deposit powder build material on a surface and an agent distribution system to selectively deposit various colored fusing agents and an ultraviolet absorbing agent on the powder build material in a pattern of a layer of a three-dimensional (3D) object to be printed. An irradiation source selectively fuses powder build material with colored fusing agent disposed thereon. The additive manufacturing system also includes a controller. The controller, per location of the layer of the 3D object to be printed 1) determines an energy absorption at the location based on an absorptivity of colored fusing agents deposited at that location and 2) determines an additive manufacturing adjustment to be made at the location to bring the energy absorption at the location to a target level.

Abstract: An example method for additive manufacturing of metals includes spreading a build material including a metal in a sequence of layers. Each layer has a respective thickness, a respective sequence position, and a respective exposed surface to receive energy from a flood energy source prior to spreading of a subsequent layer. Each respective exposed surface has a surface area of at least 5 square centimeters (cm2). Layer-by-layer, the exposed surface of each layer is exposed to the radiated energy from the flood energy source. The energy is radiated at an intensity profile and a fluence sufficient to cause a consolidating transformation of the build material in the exposed layer.