Porous electrode wire for use in electrical discharge machining and method of manufacturing the same

• US 20010014411A1
• Filed: 04/20/2001
• Published: 08/16/2001
• Est. Priority Date: 07/30/1997
• Status: Active Grant

• Current Assignee: Ki Chul Seong
• Original Assignee: Ki Chul Seong
• Inventors: Seong, Ki Chul
• Granted Patent: US 6,492,036 B2
• Time in Patent Office: Days
• US Class Current: 428/613
• CPC Class Codes: B21C 37/042 Manufacture of coated wire or bars
• CPC Class Codes: B21C 37/045 Manufacture of wire or bars with particular section or properties
• CPC Class Codes: B23H 7/08 Wire electrodes
• CPC Class Codes: C23C 28/023 only coatings of metal elements only
• CPC Class Codes: C23C 28/025 with at least one zinc-based layer
• CPC Class Codes: C23C 28/028 Including graded layers in composition or in physical properties, e.g. density, porosity, grain size
• CPC Class Codes: Y10S 428/926 Thickness of individual layer specified
• CPC Class Codes: Y10S 428/939 Molten or fused coating
• CPC Class Codes: Y10T 428/12396 Discontinuous surface component
• CPC Class Codes: Y10T 428/12438 Composite
• CPC Class Codes: Y10T 428/12458 having composition, density, or hardness gradient
• CPC Class Codes: Y10T 428/12479 Porous [e.g., foamed, spongy, cracked, etc.]
• CPC Class Codes: Y10T 428/12694 and next to Cu- or Fe-base component
• CPC Class Codes: Y10T 428/12715 Next to Group IB metal-base component
• CPC Class Codes: Y10T 428/1275 Next to Group VIII or IB metal-base component
• CPC Class Codes: Y10T 428/12792 Zn-base component
• CPC Class Codes: Y10T 428/12903 Cu-base component
• CPC Class Codes: Y10T 428/12993 Surface feature [e.g., rough, mirror]

Abstract

The present invention relates to a porous electrode wire for use in electrical discharge machining and the method of manufacturing the same. The wire improves the machining speed at least 15% compared with a conventional zinc coated wire, which results from an increased cooling ability of the wire with a cooling liquid because of the increase in the surface area of the wire having porous surface morphology. Since the surface of the porous wire presents uniform profile of outer periphery rather than surface protrusions, it does not affect machining accuracy. Further, the porous nature of the wire is expected to improve flushability during the electrical discharge machining, providing spaces to eliminate particles of the machining. Therefore, in accordance with the method of the present invention, a zinc coated wire having improved performance of machining speed and flushability compared with a conventional coated wire can be provided without additional processes.

Claims

1. An electrode wire for use in electrical discharge machining comprising;

a core wire made of a first metal including copper; and

an alloy layer formed on the core wire, wherein the alloy layer is formed by diffusion reaction between the first metal and a second metal during hot dip galvanizing in a molten bath of the second metal and the alloy layer has a higher hardness and lower elongation than the core wire or the second metal, and wherein cracks are formed in the alloy layer having direction perpendicular to the longitudinal direction of the electrode wire.

2. The electrode wire according to

claim 1

, wherein the cracks in the alloy layer and the coating layer is formed during the drawing of the core wire in the direction of the longitudinal direction.

3. The electrode wire according to

claim 1

, wherein the first metal is made of a brass.

4. The electrode wire according to

claim 3

, wherein the second metal is made of zinc, aluminum, tin or alloys thereof.

5. The electrode wire according to

claim 2

, wherein the second metal is made of zinc, aluminum, tin or alloys thereof.