A method includes illuminating a drop with a pulse of light from a light source. A duration of the pulse of light is from about 0.0001 seconds to about 0.1 seconds. The method also includes capturing an image, video, or both of the drop. The method also includes detecting the drop in the image, the video, or both. The method also includes characterizing the drop after the drop is detected. Characterizing the drop includes determining a size of the drop, a location of the drop, or both in the image, the video, or both.

A method of changing the gas content of a device (100) which comprises a first chamber (110). The method comprises: arranging the device in a first configuration, wherein the first chamber has a first internal volume; providing a flow of a first gas to the first chamber so that the gas content of the first chamber is at least partially changed; transitioning the device from the first configuration to a second configuration, wherein the first chamber has a second internal volume which is grater than the first internal volume.

Techniques for depowdering additively fabricated parts are described in which powder is separated from parts by creating a large pressure differential between the powder and parts and a nearby location. The pressure differential may cause gas to quickly flow into and/or around the powder and parts, thereby producing a force against the powder and parts. Since the powder is generally much lighter than the parts, this force may be much more effective at moving the powder than moving the parts. As a result, the powder and parts may be separated from one another. The pressure differential may be created in various ways, such as by holding the parts and part in a chamber that is pressurized with air and/or other gas(es). Rapid depressurization of the chamber may produce the aforementioned pressure differential, leading to powder movement away from the parts.

Techniques for depowdering additively fabricated parts are described in which powder is separated from parts by creating a large pressure differential between the powder and parts and a nearby location. The pressure differential may cause gas to quickly flow into and/or around the powder and parts, thereby producing a force against the powder and parts. Since the powder is generally much lighter than the parts, this force may be much more effective at moving the powder than moving the parts. As a result, the powder and parts may be separated from one another. The pressure differential may be created in various ways, such as by holding the parts and part in a chamber that is pressurized with air and/or other gas(es). Rapid depressurization of the chamber may produce the aforementioned pressure differential, leading to powder movement away from the parts.

An additive manufacturing system including an enclosure defining a build chamber, a powder bed within the build chamber, an energy source for directing a heat at the powder bed to melt a portion of the powder, a gas flow system connected to the enclosure, a gas outlet for directing gas into the build chamber for removing soot from the powder bed, and a temperature control module for controlling a build chamber temperature and a gas temperature.

An additive manufacturing system including an enclosure defining a build chamber, a powder bed within the build chamber, an energy source for directing a heat at the powder bed to melt a portion of the powder, a gas flow system connected to the enclosure, a gas outlet for directing gas into the build chamber for removing soot from the powder bed, and a temperature control module for controlling a build chamber temperature and a gas temperature.

In a method of providing a flow for a process chamber of a device for producing a three-dimensional object by layer-wise application and selective solidification of a building material in a build area a process gas is supplied to the process chamber in a lower altitude region of the process chamber, wherein the process chamber includes a gas inlet for introducing the process gas into the process chamber and a gas outlet for discharging the process gas from the process chamber. The gas inlet and the gas outlet are provided in the lower altitude region of the process chamber and the process gas flows in a main flow from the gas inlet to the gas outlet, and wherein a secondary flow is located in a sub-region of the lower altitude region, which sub-region is located above a bottom surface of the process chamber surrounding the build area.

A system and method for additive manufacturing are provided. The system includes a structure defining a chamber for manufacturing parts via additive manufacturing. A powder metal applicator is configured to deposit layers of powder metal material to build a part on a build platform. A laser source is configured to direct one or more laser beams onto each layer of powder metal material to fuse the powder metal material, wherein metal condensate is created by the laser beam(s) contacting the powder metal material. An element spaced apart from the layers of powder material has a temperature different than the chamber temperature, so that the element is configured to attract or repel the metal condensate by virtue of the temperature differential between the element and the chamber. The method includes using the element having the different temperature to attract or repel the metal condensate within the chamber.

A system and method for additive manufacturing are provided. The system includes a structure defining a chamber for manufacturing parts via additive manufacturing. A powder metal applicator is configured to deposit layers of powder metal material to build a part on a build platform. A laser source is configured to direct one or more laser beams onto each layer of powder metal material to fuse the powder metal material, wherein metal condensate is created by the laser beam(s) contacting the powder metal material. An element spaced apart from the layers of powder material has a temperature different than the chamber temperature, so that the element is configured to attract or repel the metal condensate by virtue of the temperature differential between the element and the chamber. The method includes using the element having the different temperature to attract or repel the metal condensate within the chamber.

An annular hollow offset-focus laser cladding device, including a housing, a conical reflector arranged in the housing, an annular off-axis parabolic focusing mirror opposite to and arranged coaxially with the conical reflector, a nozzle installed below the conical reflector and a powder-spraying tube connected to a lower end of the nozzle. A top of the housing is provided with a light entrance; the conical reflector faces the light entrance; The powder-spraying tube is coaxial with the annular hollow offset-focusing light reflected by the annular off-axis parabolic focusing mirror; a collimating protective gas jacket is arranged on a periphery of the powder-spraying tube, and the collimating protective gas jacket is located between the annular hollow offset-focused light and the powder-spraying tube; the annular off-axis parabolic focusing mirror is configured to create a horizontally offset of parent parabola focus.