A gas-recycling device according to an embodiment includes a particle remover, a liquid remover, and a supplier. The particle remover brings a mist of liquid into contact with a gas which includes particles and is discharged from an apparatus, to remove the particles from the gas. The liquid remover removes the liquid from the gas having passed through the particle remover. The supplier supplies the gas to the apparatus.

A gas-recycling device according to an embodiment includes a particle remover, a liquid remover, and a supplier. The particle remover brings a mist of liquid into contact with a gas which includes particles and is discharged from an apparatus, to remove the particles from the gas. The liquid remover removes the liquid from the gas having passed through the particle remover. The supplier supplies the gas to the apparatus.

A metal powder additive manufacturing system and method are disclosed that use increased trace amounts of oxygen to improve physical attributes of an object. The system may include: a processing chamber; a metal powder bed within the processing chamber; a melting element configured to sequentially melt layers of metal powder on the metal powder bed to generate an object; and a control system configured to control a flow of a gas mixture within the processing chamber from a source of inert gas and a source of an oxygen containing material, the gas mixture including the inert gas and oxygen from the oxygen containing material. The method may result in an object having a surface porosity of no greater than approximately 0.1%, and an effective density of greater than approximately 99.9%.

A metal powder additive manufacturing system and method are disclosed that use increased trace amounts of oxygen to improve physical attributes of an object. The system may include: a processing chamber; a metal powder bed within the processing chamber; a melting element configured to sequentially melt layers of metal powder on the metal powder bed to generate an object; and a control system configured to control a flow of a gas mixture within the processing chamber from a source of inert gas and a source of an oxygen containing material, the gas mixture including the inert gas and oxygen from the oxygen containing material. The method may result in an object having a surface porosity of no greater than approximately 0.1%, and an effective density of greater than approximately 99.9%.

The invention relates to a method for producing hard metal powder suitable for manufacturing hard metal products comprising metal carbides and a binder. To provide a method which is easy to carry out and which provides high quality hard metal powder, the method is characterized by the steps of: a) dissolving in water, water soluble raw materials and a binder source to form an aqueous solution, b) drying the aqueous solution to form a precursor powder having the raw materials homogenously distributed throughout the precursor powder, c) decomposing the precursor powder by heating the powder in an inert atmosphere to remove gas evolved in the decomposition of the raw materials, d) grinding the precursor powder and mixing it with a liquid media to produce a suspension, e) spray drying the suspension to agglomerate the precursor powder, and f) heat treating the agglomerated precursor powder to form a hard metal powder containing agglomerates of carbides evenly distributed and bonded to a metallic matrix.

A process for producing a metal foam. The process includes mechanically working a metallic powder such that oxide particles and/or dissolved oxygen are finely dispersed within a metallic matrix of the metallic particles that make up the metallic powder. The mechanically worked metallic powder is then annealed in a reducing atmosphere, where the reducing atmosphere is an atmosphere that results in the reduction of oxide and/or dissolved oxygen into vapor or gas molecules such that intraparticle porosity is formed within the metallic matrix by conversion of the oxide particles and/or dissolved oxygen to create vapor or gas molecules.

A process for producing a metal foam. The process includes mechanically working a metallic powder such that oxide particles and/or dissolved oxygen are finely dispersed within a metallic matrix of the metallic particles that make up the metallic powder. The mechanically worked metallic powder is then annealed in a reducing atmosphere, where the reducing atmosphere is an atmosphere that results in the reduction of oxide and/or dissolved oxygen into vapor or gas molecules such that intraparticle porosity is formed within the metallic matrix by conversion of the oxide particles and/or dissolved oxygen to create vapor or gas molecules.

Methods for preparing solid metal oxide nanoparticles via controlled oxidation comprising preparing a plurality of metal nanoparticles, contacting the plurality of metal nanoparticles with an aqueous agent to provide metal oxide nanoparticles having a desired particle size, and removing the resulting metal oxide nanoparticles from the aqueous agent. Aspects of the present disclosure also relate to solid metal oxide nanoparticles obtained by this method.

Methods for preparing solid metal oxide nanoparticles via controlled oxidation comprising preparing a plurality of metal nanoparticles, contacting the plurality of metal nanoparticles with an aqueous agent to provide metal oxide nanoparticles having a desired particle size, and removing the resulting metal oxide nanoparticles from the aqueous agent. Aspects of the present disclosure also relate to solid metal oxide nanoparticles obtained by this method.

A metal powder additive manufacturing system and method are disclosed that use increased trace amounts of oxygen to improve physical attributes of an object. The system may include: a processing chamber; a metal powder bed within the processing chamber; a melting element configured to sequentially melt layers of metal powder on the metal powder bed to generate an object; and a control system configured to control a flow of a gas mixture within the processing chamber from a source of inert gas and a source of an oxygen containing material, the gas mixture including the inert gas and oxygen from the oxygen containing material.