Methodologies and manufacturing processes to manufacture components by electron beam melting additive manufacturing, particularly components of molybdenum or a molybdenum-based alloy and particularly of complex nuclear component geometries. Input parameters are provided for controlling electron beam melting additive manufacturing equipment, such as electron beam melting machines. The input parameters relate to various process steps, including build set-up, initial thermal treatment, initial layering of powder, pre-consolidation thermal treatment, consolidation, post-consolidation thermal treatment, indexing of layers, and post-build thermal treatment. The methodologies and manufacturing processes allow manufacture of components of molybdenum having a purity of ≥99.0% and a density of ≥99.75%. Metallographic cross-sections of the manufactured molybdenum components were porosity-free and crack-free.

Methodologies and manufacturing processes to manufacture components by electron beam melting additive manufacturing, particularly components of molybdenum or a molybdenum-based alloy and particularly of complex nuclear component geometries. Input parameters are provided for controlling electron beam melting additive manufacturing equipment, such as electron beam melting machines. The input parameters relate to various process steps, including build set-up, initial thermal treatment, initial layering of powder, pre-consolidation thermal treatment, consolidation, post-consolidation thermal treatment, indexing of layers, and post-build thermal treatment. The methodologies and manufacturing processes allow manufacture of components of molybdenum having a purity of ≥99.0% and a density of ≥99.75%. Metallographic cross-sections of the manufactured molybdenum components were porosity-free and crack-free.

A Sm—Fe—N magnet includes Sm—Fe—N particles, wherein an inter-particle metal phase is present between at least two of the Sm—Fe—N particles, an average particle diameter of the Sm—Fe—N particles is less than 2.0 μm, and a percentage of the Sm—Fe—N particles having an aspect ratio of 2.0 or more is 10% or less, the inter-particle metal phase includes a Fe.sub.3Zn.sub.10 phase and an α-Fe phase in a particle form, and in the inter-particle metal phase, an area ratio of the Fe.sub.3Zn.sub.10 phase is 80% or more.

A Sm—Fe—N magnet includes Sm—Fe—N particles, wherein an inter-particle metal phase is present between at least two of the Sm—Fe—N particles, an average particle diameter of the Sm—Fe—N particles is less than 2.0 μm, and a percentage of the Sm—Fe—N particles having an aspect ratio of 2.0 or more is 10% or less, the inter-particle metal phase includes a Fe.sub.3Zn.sub.10 phase and an α-Fe phase in a particle form, and in the inter-particle metal phase, an area ratio of the Fe.sub.3Zn.sub.10 phase is 80% or more.

A porous titanium-based sintered body, having a porosity of 45% to 65%, an average pore diameter of 5 μm to 15 μm, and a bending strength of 100 MPa or more. According to the present invention, a porous titanium-based sintered body having good pore diameter and porosity that are compatible with each other and having a high strength can be provided.

A porous titanium-based sintered body, having a porosity of 45% to 65%, an average pore diameter of 5 μm to 15 μm, and a bending strength of 100 MPa or more. According to the present invention, a porous titanium-based sintered body having good pore diameter and porosity that are compatible with each other and having a high strength can be provided.

The present disclosure is directed at methods of preparing rare earth-based permanent magnets having improved coercivity and remanence, the method comprising one or more steps comprising: (a) homogenizing a first population of particles of a first GBM alloy with a second population of particles of a second core alloy to form a composite alloy preform, the first GBM alloy being substantially represented by the formula: AC.sub.bR.sub.xCo.sub.yCu.sub.dM.sub.z, the second core alloy being substantially represented by the formula G.sub.2Fe.sub.14B, where AC, R, M, G, b, x, y, and z are defined; (b) heating the composite alloy preform particles to form a population of mixed alloy particles; (c) compressing the mixed alloy particles, under a magnetic field of a suitable strength to align the magnetic particles with a common direction of magnetization and inert atmosphere, to form a green body; (d) sintering the green body; and (e) annealing the sintered body. Particular embodiments include magnets comprising neodymium-iron-boron core alloys, including Nd.sub.2Fe.sub.14B.

The present disclosure is directed at methods of preparing rare earth-based permanent magnets having improved coercivity and remanence, the method comprising one or more steps comprising: (a) homogenizing a first population of particles of a first GBM alloy with a second population of particles of a second core alloy to form a composite alloy preform, the first GBM alloy being substantially represented by the formula: AC.sub.bR.sub.xCo.sub.yCu.sub.dM.sub.z, the second core alloy being substantially represented by the formula G.sub.2Fe.sub.14B, where AC, R, M, G, b, x, y, and z are defined; (b) heating the composite alloy preform particles to form a population of mixed alloy particles; (c) compressing the mixed alloy particles, under a magnetic field of a suitable strength to align the magnetic particles with a common direction of magnetization and inert atmosphere, to form a green body; (d) sintering the green body; and (e) annealing the sintered body. Particular embodiments include magnets comprising neodymium-iron-boron core alloys, including Nd.sub.2Fe.sub.14B.

A laser-solid-forming manufacturing device includes a laser emitter, a magnetic field generator, and a forming platform. The laser emitter emits a laser beam which acts on a feedstock to form a molten pool. The magnetic field generator includes a spiral copper coil, a first electrode and a second electrode. The spiral copper coil is formed by spirally winding a copper tube. The first and second electrodes are arranged at respective ends of the copper tube and are used for loading a voltage to generate a magnetic field in the spiral copper coil. At any time, the spiral copper coil sleeves an action point of the laser beam and the feedstock. A corresponding laser-solid-forming manufacturing method is also presented.

A laser-solid-forming manufacturing device includes a laser emitter, a magnetic field generator, and a forming platform. The laser emitter emits a laser beam which acts on a feedstock to form a molten pool. The magnetic field generator includes a spiral copper coil, a first electrode and a second electrode. The spiral copper coil is formed by spirally winding a copper tube. The first and second electrodes are arranged at respective ends of the copper tube and are used for loading a voltage to generate a magnetic field in the spiral copper coil. At any time, the spiral copper coil sleeves an action point of the laser beam and the feedstock. A corresponding laser-solid-forming manufacturing method is also presented.