The present disclosure describes three-dimensional (3D) printing apparatuses, processes, software, and systems for producing high quality 3D objects. Described herein are printing apparatuses that facilitate control of energy beam characteristics using an optical mask during one or more printing operations.

The present disclosure describes three-dimensional (3D) printing apparatuses, processes, software, and systems for producing high quality 3D objects. Described herein are printing apparatuses that facilitate control of energy beam characteristics using an optical mask during one or more printing operations.

A metal powder having a BET specific surface area of 5 to 250 m.sup.2/g is obtained by contacting and mixing together a gas of a metal chloride (metal source gas) and a reducing gas (e.g., hydrogen gas) that have been separately heated so as to instantaneously form fine metal particles based on the gas phase reduction reaction thereof, and collecting the fine metal particles from the gas stream after the reaction.

A metal powder having a BET specific surface area of 5 to 250 m.sup.2/g is obtained by contacting and mixing together a gas of a metal chloride (metal source gas) and a reducing gas (e.g., hydrogen gas) that have been separately heated so as to instantaneously form fine metal particles based on the gas phase reduction reaction thereof, and collecting the fine metal particles from the gas stream after the reaction.

The present disclosure describes three-dimensional (3D) printing apparatuses, processes, software, and systems for producing high quality 3D objects. Described herein are printing apparatuses that facilitate control of energy beam characteristics using an optical mask during one or more printing operations.

The present disclosure describes three-dimensional (3D) printing apparatuses, processes, software, and systems for producing high quality 3D objects. Described herein are printing apparatuses that facilitate control of energy beam characteristics using an optical mask during one or more printing operations.

A one-dimensional titanium nanostructure and a method for fabricating the same are provided. A titanium metal reacts with titanium tetrachloride to form the one-dimensional titanium nanostructure on a heat-resistant substrate in a CVD method and under a reaction condition of a reaction temperature of 300-900 C., a deposition temperature of 200-850 C., a flow rate of the carrier gas of 0.1-50 sccm and a reaction time of 5-60 hours. The titanium nanostructure includes titanium nanowires, titanium nanobelts, flower-shaped titanium nanowires, titanium nanorods, titanium nanotubes, and titanium-titanium dioxide core-shell structures. The titanium nanostructure can be densely and uniformly grown on the heat-resistant substrate. The present invention neither uses a template nor uses the complicated photolithographic process, solution preparation process, and mixing-coating process. Therefore, the process scale-up, cost down, and the simplified production process are achieved.

A method of additive manufacturing. The method comprises: i) positioning porous particles on a substrate, the porous particles having an average porosity and comprising at least one material chosen from metals and metalloids; ii) heating at least a portion of the porous particles to a reaction temperature; and iii) exposing the porous particles to a reactant gas to form a layer comprising a non-oxide ceramic. A method of making porous particles is also disclosed.

A method of additive manufacturing. The method comprises: i) positioning porous particles on a substrate, the porous particles having an average porosity and comprising at least one material chosen from metals and metalloids; ii) heating at least a portion of the porous particles to a reaction temperature; and iii) exposing the porous particles to a reactant gas to form a layer comprising a non-oxide ceramic. A method of making porous particles is also disclosed.

A one-dimensional titanium nanostructure and a method for fabricating the same are provided. A titanium metal reacts with titanium tetrachloride to form the one-dimensional titanium nanostructure on a heat-resistant substrate in a CVD method and under a reaction condition of a reaction temperature of 300-900 C., a deposition temperature of 200-850 C., a flow rate of the carrier gas of 0.1-50 sccm and a reaction time of 5-60 hours. The titanium nanostructure includes titanium nanowires, titanium nanobelts, flower-shaped titanium nanowires, titanium nanorods, titanium nanotubes, and titanium-titanium dioxide core-shell structures. The titanium nanostructure can be densely and uniformly grown on the heat-resistant substrate. The present invention neither uses a template nor uses the complicated photolithographic process, solution preparation process, and mixing-coating process. Therefore, the process scale-up, cost down, and the simplified production process are achieved.