JPS63134118A - Electrode material for wire-cut electric discharge machining - Google Patents

Abstract

PURPOSE:To obtain a single yarn of carbon fiber which enables a machine to decrease its wearing in an electrified part and a guide part, by forming a pitch material, produced from petroleum or coal, into a fine wire to perform its firing so that the wire increases its strength with no winding habit to a reel. CONSTITUTION:A wire electrode material 1 is formed by a single yarn of carbon fiber in which a pitch material is formed into a fine wire to perform its firing. And the machining method by the wire electrode material 1 is such that it is mounted to a wire cut electric discharge machine being held by an upper part guide 2 and a bottom part guide 3 and cutting a workpiece 4. This electrode material 1, having high wire strength, can be given sufficient tension even if it is formed into a very fine wire, and the machining accuracy improves by enabling a drum phenomenon of the workpiece 4 to be prevented. While the material, providing good linearity of the wire with no winding habit to a reel, improves the smoothness of a cut surface. And the material further decreases wearing in the upper and bottom part guides 2, 3 and an electrified part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wire electrode material used in wire-cut electrical discharge machining.

[Conventional technology]

Conventional electrode materials for wire-cut electrical discharge machining include copper, brass, and tungsten wires, which have excellent strength and are easy to draw into fine wires because they are processed by applying tension to the wire, and have a low electrode wear rate. is used as an electrode material in wire-cut electric discharge machines.

Generally used wire electrode diameter is 0.2~0.2
5 mm, but it is necessary to select various wire diameters depending on the minimum radius of the corner of the workpiece.

The diameter of the fine wire electrodes currently used is 0.02~
Although 0.03++m is the thinnest wire, it is not very practical due to the relationship with the workpiece plate thickness. As a commonly used fine wire, a tungsten wire with a diameter of 0.05 mm is used for processing precision molds and the like. The minimum corner radius at this time is approximately 0.07 mm when the processed plate thickness is approximately 10 nm.

Additionally, there is a limit to the maximum machining current for the electrode diameter, and if this tolerance is exceeded, the wire will break. Therefore, there is a practical range of wire electrode diameter regarding maximum plate thickness and wire tension.
For example, in the case of a tungsten wire with a diameter of 9.05 m, the maximum wire tension is 200 g.

[Problem that the invention seeks to solve]

However, with the tungsten wire that has been used as a wire electrode for conventional micromachining, it is difficult to eliminate curls in the processing machine when it is wound around the reel, making it difficult to obtain the precision of the workpiece. In addition, there were problems such as severe wear of the current-carrying part and the guide part.

This invention was made to solve the above-mentioned problems, and it is a wire-cut electrical discharge machining method that has high wire strength, does not have curly winding on the reel, and reduces wear on the current-carrying part and guide part of the processing machine. The purpose is to obtain electrode materials for

[Means for solving problems]

The electrode material for wire-cut electrical discharge machining according to the present invention is made of a carbon fiber instep and thread made by firing a pitch material produced from petroleum or coal into fine wires as a wire electrode material. This wire electrode material consists of fine blast fibers with high strength, high elastic modulus, and low coefficient of friction.

[For production]

The wire electrode material made of carbon fiber instep and thread made of fired pitch material in this invention has a tensile strength of 250 to 300K.
g/m", and has a high tensile strength, and can apply sufficient tension to the wire to maintain the accuracy of the workpiece. Also, the tensile modulus is 30,000 to 60,000 kg/m, making it an extremely rigid wire. This is a wire with high straightness and no curling on the reel.

Moreover, since it is made of carbon fiber, the coefficient of friction is small, and wear of the current-carrying parts and guide parts of the processing machine is extremely low.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an electrode material for wire-cut electric discharge machining, and FIG. 2 is a perspective view showing a machining state.

In the figure, (1) is a wire electrode material, which is made of carbon fiber instep and thread made by firing pitch material into fine wires.

As shown in Fig. 2, the processing method using this wire electrode material (1) is to attach the wire electrode material (1) to a wire-cut electric discharge machine, and use the upper guide (2) and lower guide (3) to cut the wire electrode. Holds the material (1) and the workpiece (4)
cut.

Wire electrode material for the above wire cut electric discharge machining (1)
Due to the high strength of the wire, the diameter is 0.03~. 0.
Sufficient tension can be applied even to a fine wire of 0.05 mm, preventing the concave phenomenon (a phenomenon in which the cut surface of the workpiece becomes concave) on the workpiece (4), and improving the machining accuracy of the workpiece (4).

Also, because the tensile modulus of the wire is large.

Since there is no curl in the winding on the reel and the wire has good straightness, the cut surface has good smoothness. Moreover, since the frictional resistance is small, wear of the upper and lower guides (2) and (3) and the current-carrying part is reduced.

〔Effect of the invention〕

As described above, according to the present invention, 1. Since carbon fiber m-thread made of pitch material is used as the wire electrode material, sufficient tension can be applied to the wire, and the wire has excellent linearity, so that the workpiece can be This has the effect of improving machining accuracy and extremely reducing wear on contact parts with the processing machine and current-carrying parts.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the wire electrode material, and FIG. 2 is a perspective view showing the processed state. In each figure, the same reference numerals indicate the same parts, (1) is the wire electrode material, (2) is the upper guide, (3) is the lower guide, (
4) is a workpiece.

Claims (1)

[Claims] (1) An electrode material for wire-cut electrical discharge machining, characterized in that the electrode material is a single carbon fiber yarn made by firing pitch material produced from petroleum or coal into fine wires.