Copper alloy and method of manufacturing copper alloy

Patent metadata

Field	Value
Publication number	US-9666325-B2
Application number	US-201214008910-A
Country	US
Kind code	B2
Filing date	Mar 29, 2012
Priority date	Mar 31, 2011
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

Disclosed is a beryllium-free copper alloy having high strength, high electric conductivity and good bending workability and a method of manufacturing the copper alloy. Provided is a copper alloy having a composition represented by the composition formula by atom %: Cu100-a-b-c(Zr, Hf)a(Cr, Ni, Mn, Ta)b(Ti, Al)c [wherein 2.5≦a≦4.0, 0.1<b≦1.5 and 0≦c≦0.2; (Zr, Hf) means one or both of Zr and Hf; (Cr, Ni, Mn, Ta) means one or more of Cr, Ni, Mn and Ta; and (Ti, Al) means one or both of Ti and Al], and having Cu primary phases in which the mean secondary dendrite arm spacing is 2 μm or less and eutectic matrices in which the lamellar spacing between a metastable Cu5(Zr, Hf) compound phase and a Cu phase is 0.2 μm or less.

First claim

The invention claimed is:

1. A copper alloy having a composition represented by the composition formula by atom %: Cu 100-a-b-c (Zr, Hf) a (Cr, Ni, Mn, Ta) b (Ti, Al) c [wherein, 2.5≦a≦4.0, 0.1<b≦1.5 and 0≦c≦0.2; (Zr, Hf) means one or both of Zr and Hf; (Cr, Ni, Mn, Ta) means one or more of Cr, Ni, Mn and Ta; and (Ti, Al) means one or both of Ti and Al], and having Cu primary phases in which the mean secondary dendrite arm spacing is 2 μm or less and eutectic matrices in which the lamellar spacing between a metastable Cu 5 (Zr, Hf) compound phase and a Cu phase is 0.2 μm or less.

2. The copper alloy according to claim 1 , wherein the Cu primary phases and the eutectic matrices are layered by cold working.

3. The copper alloy according to claim 2 , wherein the cold working is rolling, and by performing aging heat treatment after the cold working, tensile strength is 1000 MPa or more, and electric conductivity is 30% IACS or more, and the ratio R min /t is 1 or less wherein t represents a plate thickness and R min , represent a minimum bending radius without causing a crack when performing bending work in the direction of the plate thickness and in the direction orthogonal to the rolling direction after aging heat treatment.

4. The method of manufacturing the copper alloy recited in claim 1 , the method comprising: dissolving a master alloy prepared by formulating each element to give a composition represented by the composition formula by atom %: Cu 100-a-b-c (Zr, Hf) a (Cr, Ni, Mn, Ta) b (Ti, Al) c [wherein 2.5≦a≦4.0, 0.1<b≦1.5 and 0≦c≦0.2; (Zr, Hf) means one or both of Zr and Hf; (Cr, Ni, Mn, Ta) means one or more of Cr, Ni, Mn and Ta; and (Ti, Al) means one or both of Ti and Al]; and then rapidly solidifying the master alloy.

5. The method of manufacturing a copper alloy according to claim 4 , comprising: performing cold working with a processing rate of between 81% and 99.5% inclusive to form a structure in which the Cu primary phases having a mean secondary dendrite arm spacing of 2 μm or less and the eutectic matrices having a lamellar spacing of 0.2 μm or less between the metastable Cu 5 (Zr,Hf) compound phase and the Cu phase are layered after the rapid solidification.

6. The method of manufacturing a copper alloy according to claim 5 , comprising: performing aging heat treatment at a temperature ranging from 300 to 450° C. for 0.5 to 2 hours after performing the cold working.

Assignees

• Inoe Akihisa
• Nishiyama Nobuyuki
• Yamazaki Haruko
• Univ Tohoku

Inventors

• Inoue Akihisa
• Nishiyama Nobuyuki
• Yamazaki Haruko

Classifications

• C22F1/08

  of copper or alloys based thereon · CPC title

• H01H1/025

  having copper as the basic material · CPC title

• H01B1/026 Primary

  Alloys based on copper · CPC title

• C22C9/00 Primary

  Alloys based on copper · CPC title

• C22C9/06

  with nickel or cobalt as the next major constituent · CPC title