Copper alloy and process for producing the same

Patent metadata

Field	Value
Publication number	US-10023940-B2
Application number	US-37864606-A
Country	US
Kind code	B2
Filing date	Mar 20, 2006
Priority date	Sep 19, 2003
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

A copper alloy consisting of two or more of Cr, Ti and Zr, and the balance Cu and impurities, in which the relationship between the total number N and the diameter X satisfies the following formula (1). Ag, P, Mg or the like may be included instead of a part of Cu. This copper alloy is obtained by cooling a bloom, a slab, a billet, or a ingot in at least in a temperature range from the bloom, the slab, the billet, or the ingot temperature just after casting to 450° C., at a cooling rate of 0.5° C./s or more. After the cooling, working in a temperature range of 600° C. or lower and further heat treatment of holding for 30 seconds or more in a temperature range of 150 to 750° C. are desirably performed. The working and the heat treatment are most desirably performed for a plurality of times.

log N ≤0.4742+17.629×exp(−0.1133× X )  (1)

First claim

The invention claimed is:

1. A copper alloy consisting of, by mass %, at least two elements selected from the group consisting of 0.01 to 5% of Cr, 0.01 to 5% of Ti and 0.01 to 5% of Zr and the balance Cu and impurities;
wherein the relationship between the total number N of precipitates and intermetallics, having a diameter of not smaller than 1 μm, which are found in 1 mm 2 of the alloy, and the diameter X in μm of the precipitates and the intermetallics having a diameter of not smaller than 1 μm satisfies the following formula (1);
log N≤ 0.4742+17.629×exp(−0.1133× X )  (1)

wherein X=1 when the measured value of the grain size of the precipitates and the intermetallics are 1.0 μm or more and less than 1.5 μm, and X=α (α is an integer of 2 or more) when the measured value is (α−0.5) μm or more and less than (α+0.5) μm.

2. The copper alloy according to claim 1 , wherein the ratio of the maximum value and the minimum value of an average content of at least one alloy element in a micro area is not less than 1.5.

3. The copper alloy according to claim 1 , wherein the copper alloy has a grain size of 0.01 to 35 μm.

4. The copper alloy according to claim 2 , wherein the grain size is 0.01 to 35 μm.

5. A method for producing a copper alloy, comprising cooling a bloom, a slab, a billet, or a ingot obtained by melting a copper alloy according to claim 1 , followed by casting in at least in a temperature range from the bloom, the slab, the billet, or the ingot temperature just after casting to 450° C. at a cooling rate of 0.5° C./s or more, so that the relationship between the total number N and the diameter X satisfies the following formula (1):
log N≤ 0.4742+17.629×exp(−0.1133× X )  (1)

wherein N means the total number of precipitates and intermetallics, having a diameter of not smaller than 1 μm which are found in 1 mm 2 of the alloy; and X means the diameter in μm of the precipitates and the intermetallics having a diameter of not smaller than 1 μm.

6. The method for producing a copper alloy according to claim 5 , further comprising performing working in a temperature range of 600° C. or lower.

7. The method for producing a copper alloy according to claim 6 , further comprising performing heat treatment of holding for 30 seconds or more in a temperature range of 150 to 750° C.

8. The method for producing a copper alloy according to claim 7 , wherein the working in a temperature range of 600° C. or lower and the heat treatment of holding for 30 seconds or more in a temperature range of 150 to 750° C. are performed for a plurality of times.

9. The method for producing a copper alloy according to claim 7 , wherein the working in a temperature range of 600° C. or lower is performed after the final heat treatment.

Assignees

• Maehara Yasuhiro
• Yonemura Mitsuharu
• Maeda Takashi
• Nakajima Keiji
• Nagamichi Tsuneaki
• Nippon Steel & Sumitomo Metal Corp

Inventors

• Maehara Yasuhiro
• Yonemura Mitsuharu
• Maeda Takashi
• Nakajima Keiji
• Nagamichi Tsuneaki

Classifications

• C22C9/00 Primary

  Alloys based on copper · CPC title

• B22D23/006

  Casting by filling the mould through rotation of the mould together with a molten metal holding recipient, about a common axis · CPC title

• C22F1/08

  of copper or alloys based thereon · CPC title

• C22F1/002

  by rapid cooling or quenching; cooling agents used therefor · CPC title

• B22D21/025

  Casting heavy metals with high melting point, i.e. 1000 - 1600 degrees C, e.g. Co 1490 degrees C, Ni 1450 degrees C, Mn 1240 degrees C, Cu 1083 degrees C · CPC title