Processes and methods related to processing and hot working alloy ingots are disclosed. A metallic material layer is deposited onto at least a region of a surface of an alloy ingot before hot working the alloy ingot. The processes and methods are characterized by a reduction in the incidence of surface cracking of the alloy ingot during hot working.

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.

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.

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.

Disclosed in this application are a large-sized high-Nb superalloy ingot and a smelting process thereof. The smelting process includes: vacuum induction melting to prepare a plurality of vacuum induction melting ingots with the same composition which are used for preparing electroslag electrodes with the same number as the vacuum induction melting ingots for use in electroslag remelting, preparing a consumable electrode from the prepared consumable electroslag electrodes, and performing vacuum consumable arc remelting for a plurality of times by using the consumable electroslag electrodes as raw material. A large-sized high-Nb superalloy ingot having a weight of 15 tons or above and a diameter of 800 mm or above can be prepared from such process.

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.

The present invention relates to a method (1) of producing a metal superalloy (10) comprising the steps of providing a charge of metal materials (2); melting said charge of metal materials (2) in an electric-arc furnace (3) to obtain a first melt (3A) of said charge of metal materials (2); solidifying (5) said first melt (3A) to obtain first ingots (5A); melting said first ingots (5A) in a V.I.D.P. furnace (6) to obtain a second melt (6A); solidifying (7) said second melt (6A) to obtain second ingots (7A); melting said second ingots (7A) in a V.A.R. furnace (8) to obtain a third melt (8A); solidifying (9) said third melt (8A) to obtain a metal superalloy (10). The method (1) is characterized in that the charge of metal materials (2) has a weight amount ranging from forty to sixty tons, and it includes a step of carrying out an A.O.D. treatment (4) on said first melt (3A) to obtain a decarburized and refined first melt (4A); said melting in the V.I.D.P. furnace (6) and said melting in the V.A.R. furnace (8) are carried out sequentially on said first melt (4A) resulting from said A.O.D. treatment (4).

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).