A nickel-based superalloy for three-dimension (3D) printing and a powder preparation method thereof are provided. The method of preparing the nickel-based superalloy and its powder includes: RE microalloying combined with vacuum melting, degassing, refining, atomization with reasonable parameters, and a sieving process. The new method significantly reduces the cracking sensitivity of the “non-weldable” PM nickel-based superalloys, and broadens the 3D printing process window. The as-printed part has no cracks, and good mechanical properties. In addition, the powder prepared by the new method has higher sphericity and better flowability, and less irregular powders. The yield of fine powders with a particle size of 15-53 μm and medium-sized powders with a particle size of 53-106 μm that are required for 3D printing is greatly improved, which meet the requirements for 3D printing of high-quality, low-cost nickel-based superalloy powder.

A nickel-based superalloy for three-dimension (3D) printing and a powder preparation method thereof are provided. The method of preparing the nickel-based superalloy and its powder includes: RE microalloying combined with vacuum melting, degassing, refining, atomization with reasonable parameters, and a sieving process. The new method significantly reduces the cracking sensitivity of the “non-weldable” PM nickel-based superalloys, and broadens the 3D printing process window. The as-printed part has no cracks, and good mechanical properties. In addition, the powder prepared by the new method has higher sphericity and better flowability, and less irregular powders. The yield of fine powders with a particle size of 15-53 μm and medium-sized powders with a particle size of 53-106 μm that are required for 3D printing is greatly improved, which meet the requirements for 3D printing of high-quality, low-cost nickel-based superalloy powder.

A method for preventing cracking of nickel-based superalloy fabricated by selective laser melting (SLM) belongs to the field of additive manufacturing (AM). The method of preparing an as-built part with a high density, no crack defects, and good mechanical properties includes: reducing the content of elements Zr and B forming low melting point phase in a nickel-based superalloy, adjusting the total content of Al and Ti in the alloy to 4.5 wt % or below, and combining with the control of special SLM process parameters. The new method has the advantages of a reasonable component design, a simple preparation process, and good performance of the as-built part, and therefore is suitable for large-scale application.

A method for preventing cracking of nickel-based superalloy fabricated by selective laser melting (SLM) belongs to the field of additive manufacturing (AM). The method of preparing an as-built part with a high density, no crack defects, and good mechanical properties includes: reducing the content of elements Zr and B forming low melting point phase in a nickel-based superalloy, adjusting the total content of Al and Ti in the alloy to 4.5 wt % or below, and combining with the control of special SLM process parameters. The new method has the advantages of a reasonable component design, a simple preparation process, and good performance of the as-built part, and therefore is suitable for large-scale application.

To provide a magnetic core having a high permeability and a high voltage resistance while having a small variation in the voltage resistance.

The magnetic core includes the magnetic powder. A total area ratio of particles of the magnetic powder in a cross section of the magnetic core is 75% or more and 90% or less. An average circularity of large size particles is 0.70 or more when the large size particles are particles extracted from the particles of the magnetic powder in the cross section of the magnetic core in the order of size from the largest size until a cumulative area ratio of the extracted particles reaches a smallest area ratio exceeding 20% of the total area ratio of the particles of the magnetic powder.

To provide a magnetic core having a high permeability and a high voltage resistance while having a small variation in the voltage resistance.

The magnetic core includes the magnetic powder. A total area ratio of particles of the magnetic powder in a cross section of the magnetic core is 75% or more and 90% or less. An average circularity of large size particles is 0.70 or more when the large size particles are particles extracted from the particles of the magnetic powder in the cross section of the magnetic core in the order of size from the largest size until a cumulative area ratio of the extracted particles reaches a smallest area ratio exceeding 20% of the total area ratio of the particles of the magnetic powder.

A method of selectively oxidizing one or more target metals in an alloy comprising target and non-target metals is provided. The method comprises the steps of: i) melting the alloy and exposing the molten alloy to simultaneous fragmentation and oxidation in the presence of an oxygenated atomizing gas under conditions sufficient to yield an oxidation potential that oxidizes the one or more target metals in the alloy and does not oxidize the non-target metal(s); and ii) allowing the treated alloy to solidify. The method is useful to purify a non-target base metal. The method is also useful to produce a metal compound comprising a desired content of one or more oxidized target metals above the theoretical maximum generally achieved by thermal plasma spray surface coating applications.

A production method of particulate materials, through centrifugal atomization (CA) is disclosed. The method is suitable for obtaining fine spherical powders with exceptional morphological quality and extremely low content, or even absence of nonspherical-shape particles and internal voids. A appropriate cost effective method for industrial scale production of metal, alloy, intermetallic, metal matrix composite or metal like material powders in large batches is also disclosed. The atomization technique can be extended to other than the centrifugal atomization with rotating element techniques.

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.