JPS6228120A - Electric discharge machining electrode - Google Patents

Abstract

PURPOSE:To form the machined surface of a work in a smooth surface with no ruggedness, by using non-oxygen copper, containing an impurity of oxide or the like to a quantity of 0.01% or less, in a material for an electric discharge machining electrode. CONSTITUTION:An electric discharge machining electrode 30 is made from non-oxygen copper containing a non-metallic impurity of oxide or the like to a quantity of 0.01% or less. Accordingly, even if the electrode is consumed as electric discharge machining advances, the electrode, preventing many fine rugged parts from being generated in a machined surface 4a of a work 4 due to the impurity of oxide or the like protruded and/or detached from a surface of the electrode, obtains the smooth machined surface 4a. This electrode is useful, for instance, in a mold machining metal mold like an IC package with necessity for accurate finishing.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to a machining electrode formed between a machining electrode formed in a predetermined shape and a workpiece, and a direct current RC
Electric discharge that melts the workpiece due to heat generated by conductor resistance, heat generation due to electron impact, and pressure due to steam generation caused by repeatedly generating pulsed arc discharge using a discharge circuit, and performs a predetermined process on the workpiece. The present invention relates to a processing device, and in particular, the present invention relates to an electrode for an electrical discharge machining device that uses electrical discharge machining to manufacture a mold that requires precision finishing of the surface, such as a mold for mold processing such as an IC pancake. be.

[Conventional technology]

Figure 2 is a schematic configuration diagram showing this type of electrical discharge machining equipment.
) is the power supply device, (2) is the servo device that controls the electrode (3) for electrical discharge machining, and (4) is the electrode (3) with the machining fluid (5).
) is a processing tank that accommodates the workpiece (4).

Pure copper (also called tough pinch steel) is mainly used as the material for the machining electrode (3), and is used to electrically discharge the workpiece (4) into a predetermined high-precision metal mold. ,
It is formed in advance into a predetermined shape, and its surface is polished to a mirror finish. Then, the electrode (3) and the workpiece (
The workpiece ( 4 ) is melted and electrical discharge machined into a predetermined shape.

[Problem that the invention seeks to solve]

As mentioned above, the trap and the electrode (
Pure copper is mainly used as the material for 3),
As shown in Figure 6 (AI VC), this pure copper usually contains many nonmetallic impurities (6) such as oxides,
As the electrical discharge machining by arc discharge progresses, Fig. 5 (B
), as the electrode (3) wears out, impurities (6
) is inserted from the front surface of the electrode (3), and the surface to be processed by Butsu Machining* (4) is machined extremely deeply into a large number of fine recesses (7a).
) and the separation of impurity (6) from electrode (3) fC
The resulting concave portion (6a) causes a large number of fine convex portions (7b
) is generated, and as shown in Figure 6 (C) VC, the processed surface of the workpiece (4) becomes rough, often resulting in a product that cannot be used as a mold at all. . In FIG. 6(B), (8) indicates air bubbles and sludge (processing waste) generated in the gap between the electrode (3) and the workpiece (4).

This invention was developed by focusing on this point, and it prevents the formation of many fine irregularities on the machined surface of the workpiece during electrical discharge machining of molds that require precision finishing on the front surface. The present invention aims to provide such an electrode for electrical discharge machining.

[Means for solving problems]

The electrode for electric discharge machining according to the present invention uses a material that does not cause impurities such as oxides to protrude or separate from the surface of the electrode even if the electrode wears out as electric discharge machining progresses due to arc discharge. It was designed to do so.

[Effect]

In this invention, as the electrode for electric discharge machining, a material is used that does not allow impurities such as oxides to protrude from the front surface of the electrode and not come off even if the electrode wears out as the electric discharge machining progresses. Therefore, a large number of fine irregularities are not generated on the surface of the workpiece.

[Embodiments of the invention]

Figures 1 (At, (B), and (C) are electrical discharge machining process diagrams using the electrode for electrical discharge machining according to the present invention, whereas the conventional electrical discharge machining process diagrams described above [Fig. 6 (A), (B)]
, (C)] and the same reference numerals refer to the same constituent members, and their explanations will be omitted.

■ is an electrode for electric discharge machining that faces the workpiece (4) with a predetermined gap, and this electrode ■ is made of oxygen-free copper with a content of nonmetallic impurities such as oxides of 0.01% or less. In order to electrical discharge machine the workpiece (4) into a predetermined high-precision mold, it is formed in advance into a predetermined shape, and -
f: The top surface is made of pure copper and polished into a border shape like the conventional electrode.

The gap between the electrodes for electric discharge machining according to the present invention is made of oxygen-free copper containing 0.01% or less of non-metallic impurities such as oxides, so the gap between the electrodes used in electrical discharge machining is
), as the electrode (3) wears out, impurities (6
) protrudes from the front surface of the electrode to form a large number of fine recesses (7a) that are deeply machined in extremely localized areas of the glue-processed surface of the workpiece (4);
A large number of fine protrusions (7b) in the unprocessed part are generated on the surface of the inclined workpiece (4) due to the recesses (6a) caused by the separation of the impurity (6) from the electrode (3). As shown in Figure 1 (B) and (C'), K
The electrical discharge machined surface (4a) of the i-workpiece (4) is formed as a smooth surface without any unevenness.

〔Effect of the invention〕

As described above, according to the present invention, the content of non-metallic impurities such as oxides can be reduced to 0 as a material for electrodes for electrical discharge machining.
．． Since oxygen-free copper with an oxygen content of 0.1% or less is used, even if the VC electrode wears out as the electrical discharge machining progresses, impurities such as oxides will not protrude from the electrode or separate from the electrode and become covered. It does not create many fine irregularities on the processed surface of the workpiece, and can be used as an electrode for electric discharge machining, which requires a precision finish on the front surface of a mold for mold processing such as an IC pan cage. It is very useful.

[Brief explanation of drawings]

Figures 1 (A), (F3), and (C) are electrical discharge machining process diagrams showing electrodes for electrical discharge machining according to the present invention. Figure 5 (A)
,(B). (q) This is an electric discharge machining process diagram using a conventional electric discharge machining electrode. In the figure, (4) is the beam workpiece, (5) is the machining fluid, and Symbols indicate the same or equivalent parts. Agent Patent Attorney Masaru Sato Figure 3 (A) (B) (C)

Claims (2)

[Claims] (1) In a device that generates a pulsed arc discharge via machining fluid in the machining gap formed between the electrode for electric discharge machining and the workpiece, there is no material suitable for the electrode for electric discharge machining. An electrode for electric discharge machining characterized by using oxygen copper. (2) The electrode for electric discharge machining according to claim 1, wherein the oxygen-free copper has a content of nonmetallic impurities such as oxides of 0.01% or less.