A metal particle for joint material includes an intermetallic compound crystal that contains Sn, Cu, Ni and Ge, in a basal phase that contains Sn and an Sn—Cu alloy, the metal particle having a chemical composition represented by 0.7 to 15% by mass of Cu, 0.1 to 5% by mass of Ni, 0.001 to 0.1% by mass of Ge and the balance of Sn, the basal phase having a chemical composition represented by 95 to 99.9% by mass of Sn, 5% by mass or less of Cu and 0.1% by mass or less of an inevitable impurity, the intermetallic compound crystal residing in the basal phase so as to be included therein, the metal particle having a particle size of 1 μm to 50 μm, the metal particle containing an orthorhombic crystal structure, and at least parts of the basal phase and the intermetallic compound crystal forming an endotaxial joint.

A metal particle for joint material includes an intermetallic compound crystal that contains Sn, Cu, Ni and Ge, in a basal phase that contains Sn and an Sn—Cu alloy, the metal particle having a chemical composition represented by 0.7 to 15% by mass of Cu, 0.1 to 5% by mass of Ni, 0.001 to 0.1% by mass of Ge and the balance of Sn, the basal phase having a chemical composition represented by 95 to 99.9% by mass of Sn, 5% by mass or less of Cu and 0.1% by mass or less of an inevitable impurity, the intermetallic compound crystal residing in the basal phase so as to be included therein, the metal particle having a particle size of 1 μm to 50 μm, the metal particle containing an orthorhombic crystal structure, and at least parts of the basal phase and the intermetallic compound crystal forming an endotaxial joint.

The present invention belongs to the technical field of metal materials for additive manufacturing, and relates to a Mn—Cu-based damping alloy powder for use in a selective laser melting (SLM) process and a preparation method thereof. The powder has chemical components in percent by weight as follows: C: ≤0.15%, Ni: 4.9-5.2%, Si: ≤0.15%, Fe: 1.8-5.0%, Cu: 20-23%, P: ≤0.03%, S: ≤0.06%, and the balance being Mn and inevitable impurities. The preparation method includes: preparation of master alloy, powdering by vacuum induction melting gas atomization (VIGA), mechanical vibrating and air classification screening under protection of an inert gas and collecting. Compared with the prior art, the powder of the present invention has a high sphericity, a high apparent density, a small angle of repose, a desired fluidity and a relatively high yield of fine powders having a size of 15-53 μm.

The present invention belongs to the technical field of metal materials for additive manufacturing, and relates to a Mn—Cu-based damping alloy powder for use in a selective laser melting (SLM) process and a preparation method thereof. The powder has chemical components in percent by weight as follows: C: ≤0.15%, Ni: 4.9-5.2%, Si: ≤0.15%, Fe: 1.8-5.0%, Cu: 20-23%, P: ≤0.03%, S: ≤0.06%, and the balance being Mn and inevitable impurities. The preparation method includes: preparation of master alloy, powdering by vacuum induction melting gas atomization (VIGA), mechanical vibrating and air classification screening under protection of an inert gas and collecting. Compared with the prior art, the powder of the present invention has a high sphericity, a high apparent density, a small angle of repose, a desired fluidity and a relatively high yield of fine powders having a size of 15-53 μm.

Ceramic-metallic composites are disclosed along with the equipment and processes for their manufacture. The present invention improves the densities of these composites by eliminating porosity through the use of a unique furnace system that applies vacuum and positive gas pressure during specific stages of processing. In the fabrication of Al.sub.2O.sub.3—Al composites, each process commences with a preform initially composed of at least 5% by weight silicon dioxide, and the finished product includes aluminum oxide and aluminum, and possibly other substances.

Ceramic-metallic composites are disclosed along with the equipment and processes for their manufacture. The present invention improves the densities of these composites by eliminating porosity through the use of a unique furnace system that applies vacuum and positive gas pressure during specific stages of processing. In the fabrication of Al.sub.2O.sub.3—Al composites, each process commences with a preform initially composed of at least 5% by weight silicon dioxide, and the finished product includes aluminum oxide and aluminum, and possibly other substances.

Provided are systems and methods for regulation of mass flow and monitoring of volumetric flow, for regulation of volumetric flow and monitoring of mass flow, and for regulation of both mass and volumetric flow of gas to a plasma torch for wire-plasma arc additive manufacturing processes, and methods for manufacturing metal objects by additive manufacturing using one or more of the systems.

Provided are systems and methods for regulation of mass flow and monitoring of volumetric flow, for regulation of volumetric flow and monitoring of mass flow, and for regulation of both mass and volumetric flow of gas to a plasma torch for wire-plasma arc additive manufacturing processes, and methods for manufacturing metal objects by additive manufacturing using one or more of the systems.

A metal three-dimensional printing method includes steps of: A) laying a layer of metal powder in a chamber, and the chamber having a first gas filled therein; B) projecting a laser on the layer of metal powder along a predetermined path, thereby allowing the metal powder in a projected area to be melted and sintered for shape forming, applying a second gas at a predetermined flow rate on a surface of the metal powder in the projected area, and preventing the metal powder in the projected area from moving due to application of the second gas; wherein the second gas allows the metal powder being projected to be cooled; C) during projection of the laser, a cooling level of the metal powder being projected is changed by changing a flow rate of the second gas, thereby changing a sintering power of the metal powder.

A metal three-dimensional printing method includes steps of: A) laying a layer of metal powder in a chamber, and the chamber having a first gas filled therein; B) projecting a laser on the layer of metal powder along a predetermined path, thereby allowing the metal powder in a projected area to be melted and sintered for shape forming, applying a second gas at a predetermined flow rate on a surface of the metal powder in the projected area, and preventing the metal powder in the projected area from moving due to application of the second gas; wherein the second gas allows the metal powder being projected to be cooled; C) during projection of the laser, a cooling level of the metal powder being projected is changed by changing a flow rate of the second gas, thereby changing a sintering power of the metal powder.