JPS61142020A - Electrode wire for wire-cut electric spark machining - Google Patents

Abstract

PURPOSE:To improve the electric-discharge characteristic and working speed by using an electrode wire which contains a specific % Zn, and the total of at least one kind among Li, Na and K in a specific % and, substantially Cu as the rest. CONSTITUTION:The content of Zn is restricted to 20-40%, because the electric- discharge characteristic is not sufficiently improved with the content less than 20%, and when the content exceeds 40%, the rate of beta-phase increases, and the working to form wire material is made difficult. Further, the content of Li, Na, and K singly or in total is limited to 0.01-2.0%, because the electric- discharge characteristic is not sufficiently improved with the content less than 0.01%, and when the content exceeds 2.0%, the casting performance is markedly deteriorated, and the superior pellet is hardly produced.

Description

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

[Conventional technology]

Traditionally, wire cut electrode wires have a wire diameter of 0.05~
A 0.25ym$OCu wire or a Cu-Zn alloy wire is used. In addition, W wire is used for some high-precision machining purposes.

Characteristics required of wire-cut electrode wires include (1) high processing speed, (2) good processing accuracy, (3) easy processing into wire rods, and (4) low cost.

Regarding the machining speed in (1), it is necessary that the electrical discharge between the wire and the workpiece be easy and stable. Regarding processing accuracy in (2), a wire rod with high tensile strength is required so that it can be stretched with high tension, and a thinner wire diameter is better (
3) It is necessary that wire rods can be easily thinned when processed into wire rods.

[Problem that the invention seeks to solve]

From this point of view, the conventional wire-cut wire material Cu
When considering wires or Cu-Zn alloy wires, Cu wires do not have very high tensile strength, are easily broken, and are inferior to Cu-Zn alloy wires in terms of processing speed. Although the processing speed of Zn alloy wire is improved over that of Cu wire, it cannot be said to be sufficient. Furthermore, W wire has high tensile strength and is mainly used for high precision machining.
O has the disadvantage that wire drawing is difficult and expensive, and is not common.In addition, in order to increase processing speed, composite electrode wires coated with metals that improve discharge characteristics, such as Zn-covered brass wires, have recently been developed. has been devised, but although such composite wires have excellent performance, they have the disadvantage that the manufacturing process is complicated and expensive.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electrode wire for wire-cut electric discharge machining that eliminates the drawbacks of the prior art described above and greatly increases machining speed.

[Means to solve the problem]

That is, 1 the gist of the present invention is that T, i
, Na, and K in predetermined amounts.

The reason why the addition of T, i, and Na completely improves the discharge characteristics and increases the machining speed is not clear at present, but it is believed that these elements have low melting points, low boiling points, and low work functions. It is presumed that there are.

In the present invention, the reason why Zn is limited to 120-40% is that if it is less than 20%, the discharge characteristics will not be improved sufficiently, and if it exceeds 40%, the β phase will increase and it will be difficult to process it into a wire. The reason why the amount of K added alone or in total was limited to 0.0L% to 2.0% is 0.01%.
If it is less than 2.0%, the discharge characteristics will not be improved sufficiently, and if it exceeds 2.0%, the castability will be extremely poor and it will be difficult to produce a healthy billet.

〔Example〕

This will be explained below based on examples.

(Example 1) An alloy having the composition shown in Table 1 was melted by adding Li, Na and Li to ordinary electrolytic copper. Melting is carried out in an Ar atmosphere, and after dissolving Cu, Znf is added to form Cu-Zn.
After forming an alloy, Li and Na were added to the Co foil.

K, etc. were wrapped and added singly or in combination. Casting was carried out in an 80 M$ iron mold, and the resulting billet I
After f-face milling, it was made into a rough drawing line of 8 cylinders f by hot extrusion.

Thereafter, the wire rod was peeled off during wire drawing and subjected to intermediate heat treatment at 2.6 mm $, and then a wire rod of 0.20 n = ++ $ was obtained.

As a comparative material, a wire rod of Cu-30% Zn alloy was also manufactured in the same manner.

Table 1 shows the castability and wire drawability. Within the composition range of the present invention, both castability and wire drawability are good;
flat i 4. J1616. A18. As shown in alloy No. 20, when the composition exceeds the composition range of the present invention.

Castability or wire drawability is significantly reduced.

(Table 1) (Example 2) 0.20 wm j' of the composition shown in Table 1
Wire-cut electrical discharge machining was performed using an alloy wire of 20 mm, using a 8KD11 material with a thickness of 20 shoes as a workpiece.

The processing speed is 100
414°16.18,20, which was impossible to wire draw in Example 1), was not tested.

Table 2 shows the wire cut electrical discharge machining results.

For the alloy wire having the composition range of the present invention, the processing speed is approximately 60 to 5
The effect is remarkable as it increases by 0.

(Table 2) [Effects of the Invention] By using the alloy wire of the present invention as an electrode wire for wire-cut electrical discharge machining, it is possible to greatly increase the machining speed, which brings about great industrial effects. It is.

Claims (1)

[Claims] (1) 20-40% Zn, 0.01 in the total of one or more of Li, Na and K
% to 2%, and the remainder essentially consists of Cu.