Electric discharge machining electrode wire and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-10399167-B2
Application number	US-201515122081-A
Country	US
Kind code	B2
Filing date	Jan 7, 2015
Priority date	Jan 7, 2015
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

An electrical discharge machining electrode wire includes a core including a copper or a copper alloy, and a covering layer that covers a periphery of the core and includes a zinc. The covering layer includes an outermost layer consisting of an ε-phase of a copper-zinc based alloy. The outermost layer has a Cu concentration of 12 to 20 mass % and a variation range within 5 mass % in the Cu concentration in a longitudinal direction of the electrode wire.

First claim

The invention claimed is:

1. An electrical discharge machining electrode wire, comprising:
a core comprising a copper or a copper alloy; and
a covering layer that covers a periphery of the core,
wherein the covering layer is consisted of an inner layer consisting of a γ-phase of copper and zinc provided on the core and an outermost layer consisting of an ε-phase of copper and zinc provided on the inner layer,
wherein the inner layer has a Cu concentration of 35 mass % to 45 mass %, and
wherein the outermost layer has a Cu concentration of 12 mass % to 20 mass % and a variation range within 5 mass % in the Cu concentration in a longitudinal direction of the electrode wire.

2. The electrical discharge machining electrode wire according to claim 1 , wherein an x-ray diffraction intensity of (0001) of the ε-phase in the covering layer is more than twice an x-ray diffraction intensity of (332) of the γ-phase in the covering layer.

3. The electrical discharge machining electrode wire according to claim 1 , wherein the core comprises a brass.

4. The electrical discharge machining electrode wire according to claim 1 , wherein the inner layer is disposed on an outer surface of the core.

5. The electrical discharge machining electrode wire according to claim 1 , wherein the outermost layer is disposed on an outer surface of the inner layer.

6. The electrical discharge machining electrode wire according to claim 1 , wherein the inner layer, as a single layer, extends from an outer surface of the core to an inner surface of the outermost layer.

7. The electrical discharge machining electrode wire according to claim 1 , wherein the inner layer abuts the core.

8. The electrical discharge machining electrode wire according to claim 7 , wherein the outermost layer abuts the inner layer.

9. The electrical discharge machining electrode wire according to claim 1 , wherein, in the electrical discharge machining electrode wire, the outermost layer is formed in a heat treatment in a range from 100° C. to 120° C.

10. The electrical discharge machining electrode wire according to claim 1 , wherein the outermost layer has the Cu concentration in a range from 14 mass % to 20 mass %.

11. The electrical discharge machining electrode wire according to claim 1 , wherein the outermost layer has the Cu concentration in a range from 15 mass % to 19 mass %.

12. The electrical discharge machining electrode wire according to claim 1 , wherein the outermost layer has the variation range within 4 mass % in the Cu concentration in the longitudinal direction of the electrode wire.

13. The electrical discharge machining electrode wire according to claim 1 , wherein the outermost layer has the variation range within 3 mass % in the Cu concentration in the longitudinal direction of the electrode wire.

14. The electrical discharge machining electrode wire according to claim 1 , wherein the γ-phase in the inner layer has a Zn concentration of 55 mass % to 65 mass %.

15. The electrical discharge machining electrode wire according to claim 1 , wherein the electrical discharge machining electrode wire is produced by a zinc electroplating in which a zinc plating layer is formed on a brass wire as the core and the core plated with zinc is drawn, wound onto a bobbin, and annealed in a predetermined temperature.

16. The electrical discharge machining electrode wire according to claim 15 , wherein the predetermined temperature is in a range from 100° C. to 120° C.

17. An electrical discharge machining electrode wire, comprising:
a core comprising a copper or a copper alloy; and
a covering layer that covers a periphery of the core,
wherein the covering layer is consisted of an inner layer consisting of a γ-phase of copper and zinc provided on the core and an outermost layer consisting of an ε-phase of copper and zinc provided on the inner layer,
wherein the inner layer has a Cu concentration of 35 mass % to 45 mass %,
wherein the outermost layer has a Cu concentration of 12 mass % to 20 mass % and a variation range within 5 mass % in the Cu concentration in a longitudinal direction of the electrode wire, and
wherein the ε-phase is expressed by CuZn 5 and the γ-phase is expressed by Cu 5 Zn 8 .

Assignees

• Hitachi Metals Ltd

Inventors

• Tsuji Takayuki
• Kuroda Hiromitsu
• Tokumitsu Tetsuya
• Kimura Takamitsu
• Shiba Yosuke
• Matsuzaki Hiroshi
• Komuro Yuichi
• Amamiya Shingo

Classifications

• H01B19/04

  Treating the surfaces, e.g. applying coatings · CPC title

• H01B1/026

  Alloys based on copper · CPC title

• C22C18/00

  Alloys based on zinc · CPC title

• B23K35/404

  Coated rods; Coated electrodes · CPC title

• B23K35/302

  Cu as the principal constituent · CPC title