JPS5919639A - Electrode wire for wire-cut electric discharge machining - Google Patents

Abstract

PURPOSE:To achieve a wire electrode having excellent machining speed and low adhesion by employing alloy composed of Cu, Zn, Al and Si as the wire electrode material. CONSTITUTION:An alloy containing Zn: 26-38wt%, Al: 0.2-1.5wt%, Si: 0.2- 1.0wt% and impurities inevitable with Cu is employed as the wire electrode material for wire-cut electric discharge machining. When adding one or more than two kinds of Mn, Sn, Mg, Zr by 0.2-1.0wt%, the machining speed and adhesion to the workpiece can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrode wire for wire electric discharge machining, and in particular, to an electrode wire that improves machining speed and reduces adhesion to a workpiece.

Wire electrical discharge machining is a process in which an electrical discharge phenomenon is caused between the wire electrical discharge machining electrode wire and the workpiece, and the heat generated by the discharge melts and cuts the workpiece. Suitable for continuous processing of workpieces such as molds.

In such wire electrical discharge machining, the finished surface condition and dimensional accuracy of the workpiece are required to be good, the electrode wire does not adhere to the workpiece, and the electrical discharge machining time is short. In order to satisfy electrical discharge machining characteristics, it is necessary to improve the efficiency of the electrical discharge phenomenon that occurs between the electrode wire and the workpiece.

Generally, in wire electric discharge machining, once the type of wire electric discharge machine and workpiece are specified, the finished surface condition, dimensional accuracy, and machining speed of the workpiece are largely influenced by the electrode wire used.

In wire electrical discharge machining, the finished surface condition and dimensional accuracy of the workpiece are also important characteristics, but when considering the cost and running costs of the wire electrical discharge machine, the machining speed (work amount per unit time) and the impact on the workpiece are important. Adhesion is emphasized.

Conventionally, hard copper wire, 65/35 brass wire, tungsten wire, etc. have been used as electrode wires depending on the purpose, but these all have inferior processing speeds, and especially hard copper wire and 65735 brass wire are difficult to process. However, there is a strong desire to improve this problem.

In view of this, as a result of various research studies, the present invention has developed an electrode wire that has excellent processing speed and less adhesion to the workpiece.
A10.2-1.5 wt%, SiQ, 2-1.0w
The electrode wire contains Cu and the remainder is Cu and unavoidable impurities. Another one of the present invention is Zn 26-38wt
%, A60.2-1.5 wt%, Si 0.2-1.
In addition to 0 wt%, any one or two or more of Mn, Sn, Mg, and Zr is added in a total of 0.2 to 1.0%.
The electrode wire is characterized in that it contains Cu and the remainder consists of Cu and unavoidable impurities.

That is, the present invention has discovered that by adding Zn, Al, and Si to 'u, the processing speed as an electrode wire can be significantly improved, the adhesion to the workpiece can be significantly reduced, and manufacturing can be facilitated. Furthermore, Mn, Sn, Mg
By adding a small amount of one or more of ZrO and ZrO, an even better electrode wire can be obtained due to the synergistic effect.

Next, the reason for limiting the amount of each element added in the present invention will be described. The reason for limiting the Zn content to 26 to 38 wt% is that when the Zn content is less than 26 wt%, the machining speed direction is small;
This is because if it exceeds 3 wt%, the amount of β phase increases and wire drawing becomes difficult. When the Al amount is less than Q, 2wt, the wire drawability is good, but the contribution to improving the processing speed is small; on the contrary, 1.
This is because if it exceeds 5 wt%, casting and cold wire drawing become difficult. This is because if the Sl content is less than Q, 2 wt%, the improvement in processing speed will be small, whereas if it exceeds l, Qwt%, casting segregation will occur and cold drawability will decrease.

The total amount of any one or two or more of Mn%Sn, Mg, and Zr added is 0.2 to 1. The reason why it is limited to Qwt% is that if the amount added is less than 0.2wt%, no significant effect can be obtained in improving processing speed and reducing adhesion to the workpiece. On the other hand, if it exceeds 1.0 wt%, a synergistic effect with Al and Si necessitates a large number of intermediate annealing operations, resulting in a decrease in wire drawing efficiency.

In the present invention, there is no problem even if unavoidable impurities are contained in an amount of 0.2 wt or less.

Next, the present invention will be explained using examples.

Cu is melted in a graphite crucible using a small high-frequency melting furnace, and while the hot water is covered with charcoal, Sl is added as a master alloy, the temperature of the hot water is calmed, Zn and M are added, and Mn is melted. ,
Zr is a master alloy, Sn and Mg are added alone, and an ingot (width 25 mm, thickness 25+ nm, length 3
50 mm) was obtained.

Next, this ingot was milled by 2 mm per side, and then
A wire with a diameter of 8 mrp was produced by heating to 50°C and hot working, and then wire drawing and annealing were repeated to produce an electrode wire with a diameter of 0.2 mrp.

The electrode wire thus obtained was attached to a wire electrical discharge machine, and the electrical discharge machining speed and adhesion state to the workpiece were examined, and the results are shown in Table 1. For comparison, conventional electrode wires were also investigated and are also listed in Table 1.

The machining speed was determined from the ratio of the amount of workpiece (ri) to the machining time (minutes). The processing speed is expressed as a relative value when the processing speed of hard copper wire is set as 100. Therefore, the larger this value is, the higher the machining speed is.

In addition, the amount of adhesion to the workpiece is determined by surface analysis using an X-ray analyzer, and the adhesion to the workpiece processed with hard copper wire is determined by
0 for comparison. Therefore, the smaller the value, the smaller the amount of adhesion to the workpiece. The manufacturing difficulty was determined by observing castability and wire drawability, and rated good as good and bad as difficult.

As is clear from Table 1, the electrode wire teeth 1 to Na16 of the present invention
is the conventional electrode wire IV! 1], 7.18, the machining speed is greatly improved, and the amount of adhesion to the workpiece is also reduced.

Also, the comparison electrode wire N119~ in which the amount of each additive element added is smaller than the composition range of the electrode wire of the present invention! '&23 is easy to manufacture, but the improvement in processing speed is small and there is no noticeable effect on the amount of adhesion.On the other hand, comparative electrode wire 1'h24~
Although Nn28 improves the processing speed, it has almost reached a saturated state, and the number of annealing increases in the middle, making it easy to break, making manufacturing difficult and increasing costs, so it is not industrially advantageous.

As explained in detail above, the polar wire is an excellent electrode wire with excellent machining speed and less adhesion to the workpiece. It has a remarkable industrial effect.

Table 1 Procedures Amendment 1 (Method) % formula % l Indication of case Japanese Patent Application No. 150870/1987 Title of invention Representative Masaya Funahashi 5 Electrode wire for wire electrical discharge machining Date of amendment order October 1988 2686 Subject of amendment: Detailed description of the invention in the specification (no change in content)

Claims (2)

[Claims] (1) Zn 26-38 wt%, A40.2-
1.5 wt%, Si0.2-1. , Qwt%, with the balance consisting of Cu and inevitable impurities. (2) 2126~38w, h16.2~1.5w
t%, Si0.2-1.0wt% and Mn, Sn, M
g, 0 in total of any one or two or more of ZrO
．． An electrode wire for wire electrical discharge machining, which contains 2 to 50% by weight and the remainder is Cu and unavoidable impurities.