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.

The invention relates to a steel wire suitable for making a spring or medical wire products which remarkably improve the performance of conventional stainless steel wire. The steel comprises (in wt. %): C: 0.02 to 0.15, Si: 0.1 to 0.9, Mn: 0.8 to 1.6, Cr 16 to 20, Ni: 7.5 to 10.5, Mo: ≤3, Al: 0.5 to 2.5, Ti: ≤0.15, N: ≤0.05, optional elements, and impurities, balance Fe, wherein the total amount of Cr and Ni is 25 to 27 wt. %, and wherein the steel has a microstructure including, in volume % (vol. %), martensite: 40 to 90, austenite: 10 to 60, and delta ferrite: ≤5.

A vacuum arc remelt apparatus comprising a crucible having a wall, said wall having an interior and an exterior opposite said interior; an electrode within the crucible proximate the interior; an ingot within the crucible and below the electrode, wherein said ingot includes a crown and shelf; and a vibration source at the exterior of the crucible proximate the crown and shelf.

A vacuum arc remelt apparatus comprising a crucible having a wall, said wall having an interior and an exterior opposite said interior; an electrode within the crucible proximate the interior; an ingot within the crucible and below the electrode, wherein said ingot includes a crown and shelf; and a vibration source at the exterior of the crucible proximate the crown and shelf.

A device for producing purified, especially high-purity, magnesium includes a reactor for vacuum distillation that is extended along a longitudinal axis (L). The reactor defines a reactor inner chamber having a heating region for heating magnesium. A crucible forms a crucible inner chamber for receiving purified magnesium vaporized and condensed by the device. A radial projection in the heating region defines a contact surface that extends essentially transverse to the longitudinal axis (L) and forms an essentially sealed connection with an edge of the crucible adjacent to the crucible inner chamber.

A device for producing purified, especially high-purity, magnesium includes a reactor for vacuum distillation that is extended along a longitudinal axis (L). The reactor defines a reactor inner chamber having a heating region for heating magnesium. A crucible forms a crucible inner chamber for receiving purified magnesium vaporized and condensed by the device. A radial projection in the heating region defines a contact surface that extends essentially transverse to the longitudinal axis (L) and forms an essentially sealed connection with an edge of the crucible adjacent to the crucible inner chamber.

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.

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.

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.