JPS6320293B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improvement in a brass-based electrode wire for electrical discharge machining. Conventionally, brass wires have been commonly used as electrode wires for electric discharge machining, but recently many attempts have been made to increase the speed of electric discharge machining in order to shorten machining time in order to improve productivity. Electrical discharge machining speed is determined by the equipment (electrical discharge machine)
The process greatly depends on the performance of the wire and the properties of the electrode wire, and the latter in particular has the potential to dramatically increase the processing speed. For this reason, there has recently been a particularly active development in improving the properties of electrode wires, but nothing that can be put to practical use in terms of performance and cost has yet to be found. By the way, brass wire is suitable as an electrode wire for electrical discharge machining because the alloy component Zn improves discharge properties and has greater high-temperature strength than copper wire, which was widely used before. This is because machining can be performed at a relatively high speed while maintaining state and dimensional accuracy. Examples of wires that can be processed faster than brass wires include tungsten wires, molybdenum wires, and other copper alloys, but all of them have the disadvantage of being difficult to process and expensive. Therefore, a practical electrode wire could be one that improves the properties of the current brass wire, and one way to do this is to add elements to the alloy that improve discharge performance, maintain high-temperature strength, and make it easier to process. is possible. In view of the above, an object of the present invention is to provide an electrode wire for electric discharge machining that can significantly improve discharge characteristics by improving the composition of a brass-based alloy. That is, the gist of the present invention is that Zn
The electrode wire for electric discharge machining is characterized by containing 20 to 50% of Be, 0.2 to 1.0% of Be, and further 0.5 to 1.0% of rare earth elements as required, and the balance being Cu. Here, regarding Zn content, if it is less than 20%,
No improvement in discharge performance can be expected by adding Zn, and if it exceeds 50%, processability such as wire drawing will be significantly reduced. Regarding the Be content, if it is less than 0.2%, it is not possible to improve the discharge performance or increase the high temperature strength by adding Be.
If it exceeds 1.0%, processability such as wire drawing will be significantly reduced. Regarding the rare earth element content, if it is less than 0.5%, it is not possible to refine the composition by adding rare earth elements and improve the processability into thin wires, and if it exceeds 1.0%, it is too high and the processability such as wire drawing is adversely affected. decreases. The present invention will be further explained below with reference to Examples shown in the table. Diameter 150mm, length obtained by melting the alloy shown in the table
A 300mm billet is hot extruded into a 10mm diameter generatrix, which is then wire drawn to a final diameter of 0.25mm.
It was made into a thin line. An electric discharge machining test was conducted using the thin wire as an electrode wire. A plate material with a thickness of 25 mm was used as the test workpiece, and the test was conducted under the conditions of a power supply voltage of 130 V and a wire tension of 800 g. The test results were evaluated based on extrusion and wire drawability, degree of wire wear during electrical discharge machining, and maximum practical machining speed. Here, the machining speed is also expressed as a relative ratio when the maximum machining speed of the Cu-Zn binary alloy is set to 1.00. Therefore, if this value is greater than 1.00, it indicates a higher processing speed than conventional brass wire, and if this value is smaller than 1.00, it indicates a lower processing speed than conventional brass wire. The symbols in the wire drawability column in the table have the following meanings. ○: Good wire drawing △: Slightly difficult wire drawing ×: Very difficult wire drawing

[Table] As the rare earth element, Mitsushi Metal, which is a mixture of rare earth elements containing 40 to 50% by weight of cerium and 20 to 40% by weight of lanthanum, was used. As explained above, according to the present invention, it is possible to obtain an extremely practical electrode wire that is easy to process and can significantly improve the electric discharge machining characteristics, particularly the electric discharge machining speed, by improving the brass-based alloy composition. can. Moreover, according to the electrode wire, the heat generated by machining can be reduced as the speed of electrical discharge machining increases, so that the surface condition and dimensional accuracy of the workpiece can be improved.

Claims (1)

[Claims] 1. 20 to 50% Zn and 0.2 to 1.0% Be by weight percentage.
An electrode wire for electrical discharge machining, characterized in that the electrode wire contains Cu and the remainder is Cu. 2 20 to 50% Zn and 0.2 to 1.0 Be in weight percentage
%, further contains rare earth elements from 0.5 to 1.0%, and the remainder
An electrode wire for electric discharge machining characterized by being made of Cu.