A method for collecting a heavy rare earth element from a heavy rare earth element-containing molten salt electrolysis residue and recycling the heavy rare earth element, the method includes: a step of mixing coarse particles of the molten salt electrolysis residue with a fluorinating material followed by firing, to fluorinate the coarse particles of the molten salt electrolysis residue; a step of pulverizing the coarse particles of the fluorinated molten salt electrolysis residue to obtain a powder of the molten salt electrolysis residue; and a step of mixing the powder of the molten salt electrolysis residue with R, an R-M alloy, or an R-M-B alloy (wherein R is one or more types of rare earth elements selected from the group consisting of Y, La, Ce, Nd, Pr, Sm, Gd, Dy, Tb, and Ho, M is a transition metal such as Fe or Co, and B is boron), heating and melting the mixture, separating a molten alloy from slag, and selectively extracting the heavy rare earth element into the molten alloy. Provided are a method for recycling a heavy rare earth element that is capable of efficiently recycling a heavy rare earth element that is rare in an alloy form similar to a product, and a method for recycling a rare earth magnet by using an alloy obtained by the recycling method.

A cold crucible structure according to an embodiment of the present invention includes a cold crucible structure according to an embodiment of the present invention includes: a cold crucible unit including hollow top and bottom caps, a plurality of segments connecting the top cap and the bottom cap, slits disposed between the segments, and a reaction area surrounded by the segments; and an induction coil unit disposed to cover the outer side of the cold crucible unit and disposed across the longitudinal directions of the segments and the slits, in which the diameter of the reaction area is defined as a crucible diameter, the crucible diameter is 100 to 300 mm, and a width of each of the slits is defined by $d_{\mathrm{slit}}\le 0.3\times \frac{\varnothing }{50}$
(mm)(where d.sub.slit is the width of each of the slits and Ø is the crucible diameter).

An induction furnace comprising a upper furnace vessel; an induction coil positioned below the upper furnace vessel; and a melt-containing vessel positioned inside the induction coil and communicably connected to the upper furnace vessel, wherein the positioning of the melt-containing vessel inside the induction coil defines a gap between an outside surface of the melt-containing vessel and an inside surface of the induction coil. A system for direct-chill casting comprising at least one an induction furnace; at least one in-line filter operable to remove impurities in molten metal; at least one gas source coupled to a feed port associated with the gas; and at least one device for solidifying metal by casting. A method of cooling an induction furnace comprising introducing a gas into a gap between an induction coil and a melt-containing vessel positioned inside the induction coil; and circulating the gas through the gap.

The present invention discloses a method for producing high-purity magnesium by semi-continuous distillation, comprising the following steps of: (1) melting crude magnesium or recycled mixed metal containing magnesium containing various impurities in a melting boiler; (2) feeding the molten crude magnesium into a second boiler by a magnesium liquid delivery pump, and maintaining a temperature of 665 C. to 700 C.; (3) sucking the high-temperature magnesium liquid into a crude distillation column in vacuum by a magnetic liquid suction pipe that is inserted into the intermediate boiler and connected to the crude distillation column. Magnesium is condensed into liquid in the rectification column, then discharged from a liquid seal of the rectification column, and ingoted in a refined magnesium die to obtain high-purity magnesium products.

This invention discloses a boron-containing titanium-based composite powder for 3D printing, consisting of 0.5%-2% by weight of titanium diboride and 98%-99.5% by weight of titanium sponge. The invention further discloses a method of preparing such composite powder, where the element boron is introduced to the titanium powder through rapid solidification, which significantly improves the solid solubility of boron in Ti, enabling the introduction of part of the boron into the titanium matrix to form supersaturated solid solutions. The reinforcement phase TiB in the boron-containing titanium-based composite powder prepared herein can be precisely controlled in grain size ranging from the nanometer scale to the micrometer scale through temperature or energy density, thereby preparing the titanium-based composite materials with different sizes of reinforcement phases to meet different mechanical requirements.

This invention discloses a boron-containing titanium-based composite powder for 3D printing, consisting of 0.5%-2% by weight of titanium diboride and 98%-99.5% by weight of titanium sponge. The invention further discloses a method of preparing such composite powder, where the element boron is introduced to the titanium powder through rapid solidification, which significantly improves the solid solubility of boron in Ti, enabling the introduction of part of the boron into the titanium matrix to form supersaturated solid solutions. The reinforcement phase TiB in the boron-containing titanium-based composite powder prepared herein can be precisely controlled in grain size ranging from the nanometer scale to the micrometer scale through temperature or energy density, thereby preparing the titanium-based composite materials with different sizes of reinforcement phases to meet different mechanical requirements.

Described is an oven (1) for melting precious and non-precious metals, non-metallic materials such as ashes, organic industrial waste, inorganic material such as ceramics, which are heat-resistant and not, in particular in the jewellery sector, comprising an outer unit (2) forming an inner space (6) and having an inductive thermal unit (3) positioned around the inner space (6); an inner unit (4) positioned in the inner space (6) and having a melting chamber (5) for a metal to be melted and operating in conjunction with the inductive thermal unit (3) in such a way that a heating of the inner unit (4) by the inductive thermal unit (3) causes the melting of the metal in the melting pot (5). In particular, the melting chamber (5) has an opening (11) for loading and unloading the metal. The inner unit (4) is rotatably mounted in a motor-driven fashion on the outer unit (2) about an axis of rotation (Z) suitable for mixing the metal contained in the melting chamber (5). Moreover, the outer unit (2) has rotatable supporting means (21) defining a tilting axis (Y) perpendicular to the axis of rotation (Z) and suitable for unloading liquid metal from the melting chamber (5).

A metal product manufacturing device is provided to remove, with higher accuracy, impurities from a molten metal of a non-ferrous metal or another metal containing the impurities, obtain the molten metal having higher purity, and obtain a high-purity non-metal product or another metal product from the high-purity molten metal.

A metal product manufacturing device is provided to remove, with higher accuracy, impurities from a molten metal of a non-ferrous metal or another metal containing the impurities, obtain the molten metal having higher purity, and obtain a high-purity non-metal product or another metal product from the high-purity molten metal.

A cold crucible structure according to an embodiment of the present invention includes a cold crucible structure according to an embodiment of the present invention includes: a cold crucible unit including hollow top and bottom caps, a plurality of segments connecting the top cap and the bottom cap, slits disposed between the segments, and a reaction area surrounded by the segments; and an induction coil unit disposed to cover the outer side of the cold crucible unit and disposed across the longitudinal directions of the segments and the slits, in which the diameter of the reaction area is defined as a crucible diameter, the crucible diameter is 100 to 300 mm, and gaps of the slits are defined by

[00001]$d_{\mathrm{slit}}0.3\frac{}{50}$

(mm)(where d.sub.slit is the gap between the slits and is the crucible diameter).