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US-20260125778-A1 - Cu-Based Alloy Powder Having Excellent Electric Conductivity

US20260125778A1US 20260125778 A1US20260125778 A1US 20260125778A1US-20260125778-A1

Abstract

Provided is a Cu-based alloy powder that is suitable for shaping by a process involving rapid melting and rapid solidification, and is capable of producing a Cu-based alloy shaped object having excellent relative density, electrical conductivity, and strength. The Cu-based alloy powder includes, in terms of % by mass, from 0.05 to 10.0% of an additive element M1 component and from 0.01 to 1.00% of a third element M2 component, with a balance of Cu and unavoidable impurities. The M1 component consists of one or more of Nd, Zr, Mo, and Cr, and the M2 component consists of one or more elements that have a solid solubility limit in the M1 component added to the alloy powder of 1.0% by mass or less.

Inventors

  • Masahiro Sakata
  • Hiroki Ikeda
  • Toshiyuki Sawada

Assignees

  • SANYO SPECIAL STEEL CO., LTD.

Dates

Publication Date
20260507
Application Date
20230201
Priority Date
20220228

Claims (10)

  1. 1 . A Cu-based alloy powder comprising, in terms of % by mass: from 0.05 to 10.0% of an additive element M1 component consisting of one or more selected from the group consisting of Nd, Zr, Mo, and Cr; and from 0.01 to 1.00% of a third element M2 component consisting of one or more elements that have a solid solubility limit in the M1 component contained in the Cu-based alloy powder of 1.0% by mass or less; the balance consisting of Cu and unavoidable impurities.
  2. 2 . The Cu-based alloy powder according to claim 1 , wherein the M2 component consists of one or more selected from the group consisting of Ag, Ni, and Sn.
  3. 3 . The Cu-based alloy powder according to claim 1 or 2 , wherein the Cu-based alloy powder has a sphericity of from 0.80 to 0.95.
  4. 4 . The Cu-based alloy powder according to claim 1 or 2 , wherein the Cu-based alloy powder has an average particle diameter Do of from 10 to 100 μm.
  5. 5 . A shaped object made of a Cu-based alloy comprising, in terms of % by mass: from 0.05 to 10.0% of an additive element M1 component consisting of one or more selected from Nd, Zr, Mo, and Cr; and from 0.01 to 1.00% of a third element M2 component consisting of one or more elements that have a solid solubility limit in the M1 component contained in the Cu-based alloy of 1.0% by mass or less; the balance consisting of Cu and unavoidable impurities, wherein not only a first precipitate consisting of Cu and the M1 component but also a second precipitate containing the M2 component are precipitated in the Cu-based alloy.
  6. 6 . The Cu-based alloy shaped object according to claim 5 , wherein the M2 component consists of one or more selected from the group consisting of Ag, Ni, and Sn, and the second precipitate is a precipitate that includes the M1 component and the M2 component.
  7. 7 . The Cu-based alloy shaped object according to claim 5 or 6 , wherein the second precipitate has a size of 1000 nm or less in terms of equivalent circle diameter.
  8. 8 . The Cu-based alloy shaped object according to claim 5 or 6 , wherein the Cu-based alloy shaped object has a relative density of 97.0% or more.
  9. 9 . The Cu-based alloy shaped object according to claim 5 or 6 , wherein the Cu-based alloy shaped object has an electrical conductivity of 70.0% IACS or higher.
  10. 10 . The Cu-based alloy shaped object according to claim 5 , obtained by an additive manufacturing method using the Cu-based alloy powder according to claim 1 .

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is the United States national phase of International Patent Application No. PCT/JP2023/003297 filed Feb. 1, 2023, and claims priority to Japanese Patent Application No. 2022-029290 filed Feb. 28, 2022, and Japanese Patent Application No. 2022-144415 filed Sep. 12, 2022 the disclosures of which are hereby incorporated by reference in their entireties. BACKGROUND Technical Field The present disclosure relates to a Cu-based alloy powder having excellent electrical conductivity that is suitable for processes involving rapid melting and rapid solidification, such as three-dimensional additive manufacturing, thermal spraying, laser coating, and weld overlaying. In particular, the present disclosure relates to a Cu-based alloy powder having excellent electrical conductivity that is suitable for additive manufacturing using a powder bed method (powder bed fusion method). Technical Considerations 3D printers are beginning to be used to create shaped objects made of metal. A 3D printer is a device that creates shaped objects by using an additive manufacturing method. Typical metal additive manufacturing methods include a powder bed method (powder bed fusion method), a metal deposition method (directed energy deposition method), and the like. In a powder bed method, laser or electron beam irradiation causes the irradiated part of the spread powder to melt and solidify. The melting and solidification cause the powder particles to fuse together. The irradiation is selectively applied to a part of the metal powder. The parts that are not irradiated do not melt, and a fused layer is formed only in the irradiated part. New metal powder is further spread over the formed fused layer, and the new metal powder is irradiated with a laser beam or an electron beam. The irradiation causes the metal particles to melt and solidify, thereby forming a new fused layer. The new fused layer is also fused to the existing fused layer. By sequentially repeating melting and solidification by irradiation, an aggregate of fused layers is gradually grown. As a result of this growth, a shaped object having a three-dimensional shape is obtained. By using such an additive manufacturing method, a shaped object having a complex shape can be easily obtained. As a powder-bed additive manufacturing method, JP2008-81840A discloses a method for producing a three-dimensional shaped object by repeating a step of spreading a metal powder for metal photolithography including an iron-based powder and one or more powders selected from the group consisting of nickel, a nickel-based alloy, copper, a copper-based alloy, and graphite, a step of irradiating the powder layer with a beam to form a sintered layer, and a step of cutting the surface of the shaped object. High conductivity is required for alloys used in high-frequency induction heating devices, motor cooling heat sinks, and the like. Cu-based alloys are suitable for such applications. Because the parts used in such applications have complex shapes, additive manufacturing methods are attracting attention, and the benefits of additive manufacturing methods can be utilized. However, since copper has a low light absorption coefficient at the laser wavelength of 1064 nm used in general-purpose laser additive manufacturing, the energy required for melting and solidification cannot be sufficiently obtained, making it difficult to produce the shaped object. Therefore, copper alloys having an improved light absorption coefficient and excellent shaping properties are being developed. For example, WO2019/039058 proposes a copper alloy having copper as a main component and that contains an additive element having a solid solution amount in copper of less than 0.2 at %. This proposal is intended to obtain mechanical strength while reducing a decrease in electrical conductivity caused by the additive element dissolving in solid solution in the copper by using an additive element that does not dissolve much in copper. In the proposal, an element that does not easily form a solid solution in copper based on a binary diagram or the like is added so it does not dissolve. SUMMARY In additive manufacturing methods, the metal material is rapidly melted and rapidly cooled to solidify. Conventional powders are unsuitable for use in processes involving such rapid melting and rapid solidification, and even if conventional powders are used, a high-density shaped object generally cannot be obtained immediately. For example, Cu powder reflects the laser light for irradiation in additive manufacturing more than other metal powders because pure Cu has a low light absorption coefficient (hereinafter, the ratio of laser light that is reflected is referred to as “laser reflection coefficient”), and thus Cu powder has poor energy efficiency and is unsuitable for additive manufacturing. When compared with the laser reflection coefficient of Fe-based alloys, Ni-based alloys, Co-based