Abstract: In the examples provided herein, a system includes an electrochemical sensor having two electrodes inserted in a fluid to be tested, where an alternative current (AC) voltage is applied across the two electrodes; an electrochemical sensor having two electrodes inserted in a fluid to be tested, wherein an alternative current (AC) voltage across the two electrodes; and a frequency response analyzer to analyze the measured the electrical response across multiple frequencies. The system also includes a memory to store a baseline of the electrical response across multiple frequencies, and a processor to determine from the stored baseline and the measured electrical response whether the electrical response is outside a predetermined range.

Abstract: Examples of the present disclosure are directed toward methods and system for reducing surface roughness of a cured three-dimensional (3D) printed object using a localized heat source. An example method includes applying a liquid solvent to the cured 3D printed object and heating the cured 3D printed object with the liquid solvent applied thereto to a temperature below a melting point of the cured 3D printed object using a localized heat source to reduce a surface roughness of the cured 3D printed object as compared to the cured 3D printed object prior to the application of heat.

Abstract: In a three-dimensional printing method example, a liquid functional agent is selectively applied. The liquid functional agent includes an alloying agent. A metallic build material is applied. The liquid functional agent is selectively applied before the metallic build material, after the metallic build material, or both before and after the metallic build material. The liquid functional agent patterns the metallic build material to form a composite layer. At least some of the metallic build material is exposed to energy to melt the at least some of the metallic build material to form a layer. Upon contact or after energy exposure, the alloying agent and the build material alter a composition of the composite layer.

Abstract: A particulate build material for three-dimensional printing can include from about 80 wt % to about 99.5 wt % of a polyamide particles, and from about 0.5 w % to about 7.5 wt % of thermally conductive particles including cubic lattice structured particles of carbon, cubic lattice structured particles of boron and nitrogen, or a combination thereof.

Abstract: A three-dimensional printing kit can include a polymer build material and a fusing agent. The polymer build material can include from about 80 wt % to about 100 wt % polymeric particles. The fusing agent can include an aqueous liquid vehicle, an electromagnetic radiation absorber to absorb radiation energy and convert the radiation energy to heat, and an endothermic decomposition compound that can undergo thermal decomposition at a temperature ranging from about 60° C. to about 400° C.

Abstract: A three-dimensional printing kit can include a polymeric build material and a fusing agent. The polymeric build material can include polymer particles having a D50 particle size from about 2 ?m to about 150 ?m. The fusing agent can include an aqueous liquid vehicle including water and an organic co-solvent, a radiation absorber to generate heat from absorbed electromagnetic radiation, and from about 2 wt % to about 15 wt % of a carbamide-containing compound.

Abstract: In a three-dimensional printing method example, a liquid functional agent is selectively applied. The liquid functional agent includes an alloying agent. A metallic build material is applied. The liquid functional agent is selectively applied before the metallic build material, after the metallic build material, or both before and after the metallic build material. The liquid functional agent patterns the metallic build material to form a composite layer. At least some of the metallic build material is exposed to energy to melt the at least some of the metallic build material to form a layer. Upon contact or after energy exposure, the alloying agent and the build material alter a composition of the composite layer.

Abstract: In a three-dimensional printing method example, a liquid functional agent is selectively applied. The liquid functional agent includes an alloying agent. A metallic build material is applied. The liquid functional agent is selectively applied before the metallic build material, after the metallic build material, or both before and after the metallic build material. The liquid functional agent patterns the metallic build material to form a composite layer. At least some of the metallic build material is exposed to energy to melt the at least some of the metallic build material to form a layer. Upon contact or after energy exposure, the alloying agent and the build material alter a composition of the composite layer.

Abstract: A three-dimensional printing kit can include a polymeric build material and a fusing agent. The polymeric build material can include polymer particles having a D50 particle size from about 2 ?m to about 150 ?m. The fusing agent can include an aqueous liquid vehicle including water and an organic co-solvent, a radiation absorber to generate heat from absorbed electromagnetic radiation, and from about 2 wt % to about 15 wt % of a carbamide-containing compound.

Abstract: Some examples include an additive manufacturing build object including an electrical component and a build object body. The electrical component having a varying electrical resistivity within a resistivity range of 109 ohms per square to 105 ohms per square, the resistivity range obtained by an application and fusing of a fusing component of a printing agent and build material, the printing agent applied to the build material at a predetermined saturation dosage range corresponding to the resistivity range. The build object body having a second electrical resistivity obtained by an application and fusing of the fusing component of the printing agent and the build material, the printing agent applied at a dosage below the predetermined saturation dosage range, the build object body being electrically non-conductive.

Abstract: Some examples include an additive manufacturing method for controlling electrostatic discharge of a build object. The method includes receiving data related to a build object, the data including conductivity data, selectively depositing a first portion of a printing agent onto a build material layer in a pattern of an object layer of a build object, the printing agent being electrically conductive at a predetermined dosage, the first portion deposited at less than the predetermined dosage, selectively depositing a second portion of the printing agent onto the build material layer at an area of the pattern, the printing agent at the area deposited at or above the predetermined dosage, and applying fusing energy to form the object layer, the object layer of the build object including a shell formed at the area and a core, the shell being electrically conductive and the core being electrically non-conductive.

Abstract: A system and method for additive manufacturing (AM) including forming a product via AM, placing a resonator adjacent the product as the product is being formed in the AM, and determining a property of the product. The resonator operates over a microwave frequency spectrum and emanates electromagnetic energy.

Abstract: An amorphous thin metal film can comprise a combination of three metals or metalloids including: 5 at % to 90 at % of a metalloid selected from the group of carbon, silicon, and boron; 5 at % to 90 at % of a first metal selected from the group of titanium, vanadium, chromium, iron, cobalt, nickel, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium, hafnium, tantalum, tungsten, osmium, iridium, and platinum; and 1 at % to 90 at % of cerium. The three elements may account for at least 50 at % of the amorphous thin metal film.

Abstract: Some examples include an additive manufacturing build object including an electrical component and a build object body. The electrical component having a varying electrical resistivity within a resistivity range of 109 ohms per square to 105 ohms per square, the resistivity range obtained by an application and fusing of a fusing component of a printing agent and build material, the printing agent applied to the build material at a predetermined saturation dosage range corresponding to the resistivity range. The build object body having a second electrical resistivity obtained by an application and fusing of the fusing component of the printing agent and the build material, the printing agent applied at a dosage below the predetermined saturation dosage range, the build object body being electrically non-conductive.

Abstract: An example build material spreader for a three-dimensional (3D) object printer has a spreader surface to contact a build material and spread the build material in a build material layer by translating the build material spreader through a bed of the build material to shear the build material and form a smooth exposed surface of the build material layer. The spreader surface has a surface energy less than a maximum surface energy.

Abstract: A system and method for additive manufacturing (AM) including forming a product via AM, placing a resonator adjacent the product as the product is being formed in the AM, and determining a property of the product. The resonator operates over a microwave frequency spectrum and emanates electromagnetic energy.

Abstract: In one example in accordance with the present disclosure a fluid property sensing device is described. The fluid property sensing device includes a substrate having a trench formed therein. The trench includes a bottom surface and opposite side surfaces. A first electrode is disposed on a first side surface of the trench and a second electrode is disposed on a second side surface of the trench. The first electrode and second electrode form a capacitor to measure a complex impedance of a fluid that fills a space between the first electrode and the second electrode. This complex impedance indicates a property of the fluid. A fluid level sensing die, having a number of fluid level sensing components disposed thereon, may be attached to the substrate, preferably in such a way that the fluid level sensing die is surrounded by the trench. In this way the surface area of the electrodes provided in the trench can be increased. The number of level sensing components may be thermal sensing components.

Abstract: Some examples include an additive manufacturing method for controlling electrostatic discharge of a build object. The method includes receiving data related to a build object, the data including conductivity data, selectively depositing a first portion of a printing agent onto a build material layer in a pattern of an object layer of a build object, the printing agent being electrically conductive at a predetermined dosage, the first portion deposited at less than the predetermined dosage, selectively depositing a second portion of the printing agent onto the build material layer at an area of the pattern, the printing agent at the area deposited at or above the predetermined dosage, and applying fusing energy to form the object layer, the object layer of the build object including a shell formed at the area and a core, the shell being electrically conductive and the core being electrically non-conductive.

Abstract: An example device in accordance with an aspect of the present disclosure includes a sensor, a controller, and an injector. The sensor is to provide sensor output regarding fluid chemistry of a fluid of a cooling system. The controller is to identify attributes of the fluid. The injector is to inject at least one additive into the fluid to bring at least one attribute into a threshold range.

Abstract: An example device in accordance with an aspect of the present disclosure includes a collection engine and a correlation engine to identify cooling loop characteristics. The collection engine is to collect data from devices associated with cooling loops. The correlation engine is to identify, based on the data collected, a common loop from among the cooling loops, and which of the devices are associated with the common loop.