A three-dimensional (3D) printer and method of additive manufacture are disclosed. The method includes building a three-dimensional (3D) object via a 3D printing process. After the 3D printing process, the 3D object is contained within a cake comprising the 3D object and partially fused excess build material. The method further includes vibrating the cake to loosen the excess build material. The frequency of the vibration is swept across a predetermined range of frequencies over a predetermined sweep interval.

A three-dimensional (3D) printer and method of additive manufacture are disclosed. The method includes building a three-dimensional (3D) object via a 3D printing process. After the 3D printing process, the 3D object is contained within a cake comprising the 3D object and partially fused excess build material. The method further includes vibrating the cake to loosen the excess build material. The frequency of the vibration is swept across a predetermined range of frequencies over a predetermined sweep interval.

A method based on fluidizing for modifying and preparing low-cost titanium powders for 3D printing includes: using hydrogenated-dehydrogenated irregularly-shaped titanium powders as the raw material, adding the titanium powders to a fluidized bed reactor, and introducing Ar or H.sub.2 at the flow rate of 0.5-1.5 L/min, heating the reactor to 300-700 C., and fluidizing for 5-90 min to modify the titanium powders. When filled with high-purity argon gas and heated at high temperature, the sharp edges and corners of irregularly-shaped titanium powders are ground collision of the particles due to the friction among powder particles.

A method based on fluidizing for modifying and preparing low-cost titanium powders for 3D printing includes: using hydrogenated-dehydrogenated irregularly-shaped titanium powders as the raw material, adding the titanium powders to a fluidized bed reactor, and introducing Ar or H.sub.2 at the flow rate of 0.5-1.5 L/min, heating the reactor to 300-700 C., and fluidizing for 5-90 min to modify the titanium powders. When filled with high-purity argon gas and heated at high temperature, the sharp edges and corners of irregularly-shaped titanium powders are ground collision of the particles due to the friction among powder particles.

A method for removing a residual powder from an internal compartment of an additively manufactured article includes discharging a first burst of pressurized fluid into the internal compartment through a first end, and vacating at least a portion of the residual powder through a second end valve at a second end.

A method for removing a residual powder from an internal compartment of an additively manufactured article includes discharging a first burst of pressurized fluid into the internal compartment through a first end, and vacating at least a portion of the residual powder through a second end valve at a second end.

In additive manufacturing, a composite build material filament and a release material filament are dropped from respective spools to a print head. Each of the composite build material filament and the release material filament includes a metal or ceramic powder plus a binder. On the spools and over the drop height, the filaments are heated to a temperature that flexes the filaments but does not soften them to a breaking point. The drop height is of similar linear scale to the build plate. The materials are debound and sintered.

A method for abrasive flow machining includes moving an abrasive media through a high-aspect passage of a workpiece. Local pressure of the abrasive media is increased at target abrasion surfaces of the high-aspect passage using a passage geometry that is configured to direct flow of the abrasive media into the target abrasion surfaces such that the target abrasion surfaces are preferentially polished by the abrasive media over other, non-targeted surfaces of the high-aspect passage at which the flow of the abrasive media is not directed into.

A powder cleaning system can include a fluidized bed reactor configured to retain powder and fluidize the powder to remove adsorbate and/or other contaminants from the powder, at least one inlet line, and one or more gas sources configured to be in selective fluid communication with the fluidized bed reactor via the at least one inlet line to selectively provide an inlet flow having one or more gases to the fluidized bed reactor to fluidize the powder with the one or more gases within the fluidized bed reactor. The system can include at least one outlet line in fluid communication with the fluidized bed reactor and configured to allow removal of outlet flow which comprises the adsorbate and/or other contaminants from the fluidized bed reactor.

A powder cleaning system can include a fluidized bed reactor configured to retain powder and fluidize the powder to remove adsorbate and/or other contaminants from the powder, at least one inlet line, and one or more gas sources configured to be in selective fluid communication with the fluidized bed reactor via the at least one inlet line to selectively provide an inlet flow having one or more gases to the fluidized bed reactor to fluidize the powder with the one or more gases within the fluidized bed reactor. The system can include at least one outlet line in fluid communication with the fluidized bed reactor and configured to allow removal of outlet flow which comprises the adsorbate and/or other contaminants from the fluidized bed reactor.