JP6980886B2 - Electrode line for fine electric discharge machining, manufacturing method and application - Google Patents

Description

The present application relates to the field of machine manufacturing, and particularly to electrode wires for fine electric discharge machining, manufacturing methods and applications.

With the evolution of products to smaller size and precision, fine electric discharge machining technology has attracted attention in academia and industry due to its ultra-fine and high-precision machining features as one of the non-contact precision manufacturing methods. It has already become an important component of the micromachine manufacturing field and is widely applied in the manufacturing industry.

Micro electric discharge machining (micro EDM) is a special processing method that corrodes and removes conductive materials by utilizing the electric corrosive action generated during pulse discharge between two electrodes immersed in the processing liquid, and is micro electric discharge machining or fine electricity. Also called corrosion machining, it is mainly used to machine molds and parts with small holes and cavities of complex shapes, such as drilling holes in gas films on aviation engine blades, drilling engine oil nozzles, etc. Hole machining of chemical fiber extrusion nozzles, hole machining of precision parts such as clock gears or decorations, hole machining of parts in meters of medical equipment, fine mold machining, etc.

There are many factors that affect fine electrical discharge machining, such as high frequency power supplies, tool electrodes, assembly accuracy, control systems, process design and working media, all of which are the machining accuracy of minute holes and cavities. And directly affect the surface quality. The tool electrode is the key to the constraint for realizing ultra-fine and high-precision machining of fine discharge. Because, in order to machine very small holes and microcavities, it is first necessary to obtain smaller and more accurate tool electrodes. By conducting research on the online production of tool electrodes with fine electric discharge, it is possible to meet the high precision requirements of fine electric discharge machining at the maximum, which is dedicated to fine electric discharge machining for machining fine holes and small members. It is the key to realize ultra-fine and high-precision machining technology.

Wire EDM (WEDG) is a method of manufacturing tool electrodes online in fine electric discharge machining, and continues to corrode and remove excess parts of the tool electrodes by point discharge between the copper / brass electrode lines and the tool electrodes. By doing so, various fine and irregularly shaped tool electrodes are machined. However, due to the effects of high energy release, uneven electric spark distribution and discontinuous electric spark corrosion, interference of discharge explosive force and delay in removal of machining debris caused by the capacitance effect of the traditional electrode wire, the electrode wire and the electrode wire The gaps between the tool electrodes are changed, which in turn affects the surface quality of the tool electrodes, the smoothness is poor, there are many minute cracks, and the machining accuracy of the fine discharge tool electrodes is greatly reduced.

Therefore, the WEDG method can machine micron level tool electrodes, but with the same machining electrical parameters, the same machine tool, the same machine tool and electrode material for tool electrodes given the design size. Even after repeated tests, the accuracy of the obtained tool electrodes still cannot meet the requirements, and in particular, the positioning accuracy and shape accuracy (here, roundness) of the electrodes have a very large variation range. It fluctuates within, and further evolution is expected.

The present invention provides an electrode wire for fine electric discharge machining that can improve online machining accuracy and surface quality.

The present invention can also manufacture an electrode wire having an amorphous outer layer, and also provides a method for manufacturing the electrode wire for fine electric discharge machining, which is used for high-precision fine electric discharge machining.

The present invention also provides an application of the electrode wire for fine electric discharge machining, which can improve the accuracy of fine electric discharge machining.

One of the technical solutions of the present invention provides an electrode wire for fine electric discharge machining. The electrode wire for fine electric discharge machining includes a core material whose material is brass and a surface layer that covers the outside of the core material, and the surface layer includes an inner layer that covers the outer surface of the core material and an outer surface of the inner layer. It is characterized by including a cover and an outer layer which is an amorphous layer. Amorphous as described in the present invention means that the structure exhibits an amorphous or glassy state, and the fine structure is short-range and ordered, and long-range and disordered. Atoms in the amorphous layer are irregularly arranged, disordered at long distances, have high resistance, and have very high capacitance effect resistance, which greatly reduces the high energy emission of the electrode line due to the capacitance effect and discharges. A uniform electric spark distribution can be formed in the process. The structure of the amorphous layer exhibits a short-range, orderly, amorphous or glassy structure, with a large amount of microspace in the structure, a relatively low density, a higher melting point, and a high temperature ablation phenomenon. Almost none. Since the structure is amorphous or glassy, the structure is not continuous, and the material is hard and brittle. Therefore, the electrode wire has a relatively small coefficient of thermal expansion and a relatively strong peak current resistance. .. Therefore, it is possible to prevent the electrode wire from burning out or being deformed in the discharge process, and to reduce the phenomenon of heat erosion and unevenness on the surface of the tool electrode. Further, the electrode wire having the structure can improve the online processing accuracy and the surface quality.

Further, the outer surface of the inner layer exhibits a relaxed and / or reconstructed surface structure. The relaxed or reconstructed surface structure here means that the vertical and horizontal arrangement of atoms on the outer surface of the inner layer is altered compared to its interior. In the vertical direction, atoms such as copper, zinc, iron, sulfur and silicon are moving from their original positions, that is, surface relaxation occurs, which causes trace element atoms to be the outermost regions of the surface. Located in. Laterally, the spacing between these atoms is irregular, causing surface reconstruction, which causes two or more atoms to approach each other to form an aggregate of atoms. Therefore, the arrangement of atoms on the outer surface of the inner layer becomes very irregular, the volume of the crystal cell expands, the surface relaxes, and the structure of the crystal is reconstructed. Such a structure can reduce the energy of the system and is very advantageous for adsorbing foreign atoms or molecules to form an outer layer into an amorphous layer. In addition, based on the theory of surface tension, bubbles can escape from the surface structure of relaxation or reconstruction, and the direct interference of the instantaneous explosive force with respect to the gap between the electrode line and the fine electrode can be greatly reduced, and fine electric discharge machining can be performed. It is advantageous to improve the accuracy of.

The amorphous layer is composed of 49.5 to 90 wt% Zn, 1.5 to 42 wt% Cu, and 0.158 to 6.6% X, which are chemical elements, and the remaining amount is O (oxygen). .. In addition, X contains at least three different elements X1, X2, X3, X1 is Fe, Al or Ca, X2 is Si, C, S or B, and X3 is Fe, Al, Ca. , Si, C, S or B, any one different from X1 and X2. The amorphous layer may contain unavoidable impurities having a total content of 0.3 wt% or less. The mixed structure of the amorphous layer reduces the discharge wear of the electrode wire itself, realizes continuous and stable fine discharge corrosion, ensures that the gap between the electrode wire and the fine tool electrode is constant, and is a fine tool. The surface quality of the electrode is improved, the smoothness is high, and minute cracks do not occur. In addition, the main element of the metal of the surface layer is zinc, which has a very good gasification effect, contributes to increasing the discharge efficiency, increases the processing speed, and saves the processing time.

Further, the inner layer is a β-phase or β'phase copper-zinc alloy, which has excellent conductive performance and is advantageous in that fine electric sparks are point-discharged to corrode the tool electrode.

Further, the amorphous layer completely or incompletely covers the outer surface of the inner layer.

The thickness of the amorphous layer is 1 to 10 μm, and the thickness of the inner layer is 5 to 50 μm.

The proposed technology has the following beneficial effects.

Since the non-electrostatic layer having the special structure has the characteristics of high resistivity, high melting point, low expansion coefficient, and high resistance to capacitance effect, the entire electrode line has better conductivity, tensile strength and product. It has plasticity and toughness, not only can improve machining accuracy, but also can remove stress and reduce deformation, and the machined surface is smooth, free of burns, free of microcracks, and machined quality. (For example, the surface roughness can reach Ra 0.05 μm).

Another technical proposal of the present invention provides a method for manufacturing an electrode wire for fine electric discharge machining. The method for manufacturing the electrode wire for fine discharge processing is as follows: a core material manufacturing step (1) for forming a brass bus having a diameter of 0.5 to 1.5 mm, and degreasing the bus obtained in step (1). , Acid washing, water washing and electroplating treatment to form a brass plating layer with a thickness of 0.5 to 50 μm on the bus, and the electroplating step (2) to obtain the first semi-finished wire rod. The first wire semi-finished product obtained in step (2) is alloyed at 50 to 550 ° C. to form a second wire semi-finished product composed of a brass core material, an inner layer and an initial outer layer. (3) and the second wire semi-finished product obtained in step (3) are layer-coated by powder metallurgy, the treatment temperature is 300 to 1000 ° C, and the temperature fluctuation in the treatment process is 20 ° C. Obtained in steps (4) and (4) of powder metallurgy, which is within the range and is cooled to 100 ° C. or lower and then removed from the kiln to form a third wire wire semi-finished product composed of a brass core material, an inner layer and an amorphous outer layer. The third wire semi-finished product is subjected to multimode continuous stretching and online stress relaxation annealing processing, and a stretching step (5) to obtain a finished product of the electrode wire having a diameter of 0.05 to 0.25 mm. ) And.

The chemical components of the electroplating solution in step (2) are carbon, nitrogen, oxygen, and hydrogen having a total concentration of 0.1 to 400 g / L, and the total concentration is 0.5 to 600 g / L. It contains boron, sulfur, chlorine, aluminum having a concentration of 1.2 to 1000 g / L, and zinc having a concentration of 100 to 1500 g / L. The electroplating in step (2) has a speed of 10 to 500 m / min, a current of 1200 to 2500 A, and a voltage of 120 to 220 V.

The cooling time in step (4) is 5 to 30 minutes.

Further, in step (5), the stretching speed is 600 to 1500 m / min, the annealing voltage is 12 to 60 V, and the annealing current is 15 to 50 A.

The proposed technology has the following beneficial effects.

In this manufacturing method, the outer layer is an amorphous layer, and an electrode wire applicable to fine electric discharge machining can be obtained. The electrode wire has high performance, long life, high geometrical shape matching, and can be applied to high-precision tool electrode machining and limit size machining. In addition, based on the actual machining requirements, we can meet the requirements for fine electric discharge machining of various complicated shapes, for example, cylindrical, conical, prismatic, threaded and inclined electrodes (multi-axis interlocking digital control system). It is necessary to arrange it), and it is easy to realize the automated formation of tool electrodes. In addition, the manufacturing method has a simple production process, high operability, few manufacturing steps, simple production equipment, easy to obtain products that meet the requirements, and realizes scaled and automated production. Cheap.

Another technical proposal of the present invention provides an application of an electrode wire in fine electric discharge machining.

The proposed technology has the following beneficial effects.

Due to the amorphous structure of the electrode wire covered with the outer surface, the high energy emission due to the capacitance effect is greatly reduced, so that a uniform electric spark distribution can be formed in the discharge process.

The amorphous mixed structure reduces the discharge wear of the electrode wire itself, realizes continuous and stable fine discharge corrosion, and can guarantee that the gap between the electrode wire and the fine tool electrode is constant, so that it is fine. The surface quality of the tool electrode is improved, the smoothness is high, and minute cracks do not occur.

Since the electrode wire itself constantly moves and feeds in one direction in the discharge process, and the fine tool electrode constantly rotates, the fact that the electrode wire according to the present invention has a special structure is the adhesiveness of the medium. The resistance of the work can be effectively reduced, the discharge of work chips becomes easier, and the excessive accumulation of galvanic corrosion products in the discharge gap is avoided. Therefore, the occurrence of abnormal discharge is reduced and the quality of the machined surface is improved.

Since the roughness value generated by processing with the electrode wire of the present invention is clearly smaller than the roughness value generated by discharging with the brass wire, the fine tool electrode machined with the electrode wire of the present invention is used. The altered layer is smaller, which is advantageous for extending the service life of fine tool electrodes.

FIG. 1 is a schematic diagram of a basic member for fine electric discharge machining. FIG. 2 is a schematic local cross-sectional view of the finished product of the electrode wire of the present invention. FIG. 3 is a schematic cross-sectional view of the first wire rod of the present invention. FIG. 4 is a schematic cross-sectional view of the second wire rod of the present invention. FIG. 5 is a schematic cross-sectional view of the third wire rod of the present invention.

Hereinafter, the present invention will be described in more detail using specific embodiments, but the present invention is not limited to the following specific embodiments.

The following embodiments do not limit the scope covered by the present invention, the steps described do not limit the order of execution thereof, and the directions of description are limited to the drawings only. Those skilled in the art will be within the scope of the claims of the present invention even if they make obvious improvements to the present invention using existing common sense.

The difference between fine electric discharge machining and traditional electric discharge machining is that the size of the object to be fine electric discharge machining is at the micron level, so the pulse energy of the fine electric discharge machine is very small, usually ^10-6 to ^10-7 J. .. Therefore, fine electric discharge machining usually requires a relatively long time. Further, since the electric discharge corrosion removal in the fine electric discharge machining is mainly a process of thermal melting of the workpiece material, if the energy of the pulse is high, the volume of the workpiece corrosion removal becomes large and the corresponding machining efficiency also becomes high. , The roughness of the surface of the workpiece and the discharge gap are also increased, and it is difficult to guarantee the machining accuracy. Therefore, it is difficult to combine machining efficiency and accuracy for fine electric discharge machining of a single electrode. In addition, the electrode wear of fine electric discharge machining is more severe than that of normal low-speed wire electric discharge machining, and it is difficult to guarantee the conformity of the shapes of fine tool electrodes if the electrodes are compensated by the traditional electrode replacement method. Not only that, it is difficult to guarantee the positioning accuracy when remounting.

The fine electric discharge machining technology has merits such as non-contact type, high accuracy, no burrs, and can be machined after heat treatment, and is applied to the precise production of minute structural parts of conductive materials. For fine electric discharge machining of fine structures, it is necessary to use fine tool electrodes suitable for process processes. FIG. 1 shows the basic members of the current fine electric discharge machining.

The technical proposal according to the present invention provides an electrode wire for fine electric discharge machining. As shown in FIG. 2, the electrode wire for fine electric discharge machining includes a core material whose material is brass and a surface layer that covers the outside of the core material, and the surface layer is an inner layer that covers the outer surface of the core material. It is characterized by covering the outer surface of the inner layer and including an outer layer which is an amorphous layer. The electrode wire according to the present invention has an amorphous structure that covers the outer surface, so that atoms are arranged irregularly (the arrangement of atoms is not long-range order), the resistance is high, and the resistance to the capacitance effect is very high. High energy emissions due to the effect can be significantly reduced and a uniform electric spark distribution can be formed in the discharge process. The outer layer of the electrode line of the present invention is an amorphous material, which is characterized by an amorphous or glassy structure, and the arrangement of atoms has short-range order, that is, a quality point in a local region. Although the arrangement format is similar to that of crystals, these locally regularly arranged regions are highly dispersed, with a large amount of fine space in these structures, relatively low density, and a higher melting point. High and almost no high temperature ablation phenomenon. Since the structure is amorphous or glassy, the structure is not continuous, and the material is hard and brittle. Therefore, the electrode wire has a relatively small coefficient of thermal expansion and its ability to withstand peak current is compared. Strong target. Therefore, it is possible to prevent the electrode wire from burning out or being deformed in the discharge process, and to reduce the phenomenon of heat erosion and unevenness on the surface of the tool electrode. Further, the accuracy and surface quality of fine electric discharge machining online machining can be improved.

The outer surface of the inner layer preferably exhibits a relaxed (relaxed) and / or reconstructed surface structure. Based on the theory of surface tension, bubbles can escape from the relaxed or reconstructed surface structure, and the direct interference of the instantaneous explosive force with respect to the gap between the electrode line and the fine electrode can be greatly reduced, and the accuracy of fine electric discharge machining can be improved. It is advantageous to increase. The chemical element of the amorphous layer is composed of 49.5 to 90 wt% Zn, 1.5 to 42 wt% Cu, and 0.158 to 6.6% X, and the remaining amount is O. X comprises at least three different elements X1, X2, X3, X1 is Fe, Al or Ca, X2 is Si, C, S or B and X3 is Fe, Al, Ca, Si. , C, S or B, which is any kind different from X1 and X2, and the total content of other unavoidable impurities is 0.3 wt% or less. "X comprises at least three different elements X1, X2, X3, X1 is Fe, Al or Ca, X2 is Si, C, S or B and X3 is Fe, Al, Ca. "It is any one of Si, C, S or B that is different from X1 and X2." In contrast to the example of X, X contains at least three different elements, for example, X1 is Fe. Yes, if X2 is Si, it should be understood that X3 is any one of Al, Ca, C, S or B. The mixed structure of the amorphous layer reduces the discharge wear of the electrode wire itself, realizes continuous and stable fine discharge corrosion, ensures that the gap between the electrode wire and the fine tool electrode is constant, and is a fine tool. The surface quality of the electrode is improved, the smoothness is high, and minute cracks do not occur. In addition, the main element of the metal of the surface layer is zinc, which has a very good gasification effect, contributes to increasing the discharge efficiency, increases the processing speed, and saves the processing time.

The inner layer of the electrode wire is preferably a β-phase or β'phase copper-zinc alloy, which has excellent conductivity and is advantageous in that fine electric sparks are point-discharged to corrode the tool electrode. The β-phase or β'phase copper-zinc alloy represents a copper-zinc alloy containing about 45% to 51% zinc. At a constant ambient temperature, the alloy structure has regular and constant brittleness and is usually referred to as the β'phase, above which the structure becomes irregular and is referred to as the β phase. The conversion between the β and β'phases is unavoidable, but has a very small effect.

The amorphous layer completely or incompletely covers the outer surface of the inner layer. The thickness of the amorphous layer is preferably 1 to 10 μm, and the thickness of the inner layer is 5 to 50 μm.

The method for manufacturing an electrode wire includes the following basic steps.
(1) Manufacture of core material: A brass bus having a diameter of 0.5 to 1.5 mm is formed, and the components of the brass core material are 57.5 to 71.5 wt% Cu and 0.003 to 0.30 wt%. Fe, 0.001 to 0.10 wt% Si, and the remaining amount is Zn.
(2) Electroplating: The bus obtained in step (1) is subjected to degreasing, pickling, washing with water and electroplating to form a zinc-plated layer having a thickness of 0.5 to 50 μm on the bus. Then, the first semi-finished wire rod was obtained, and FIG. 3 shows the cross section thereof. The chemical components of the electroplating solution are carbon, nitrogen, and oxygen having a total concentration of 0.1 to 400 g / L. , Hydrogen, boron, sulfur and chlorine having a total concentration of 0.5 to 600 g / L, aluminum having a concentration of 1.2 to 1000 g / L, and zinc having a concentration of 100 to 1500 g / L. Including, electroplating has a speed of 10 to 500 m / min, a current of 1200 to 2500 A, and a voltage of 120 to 220 V.
(3) Alloying: The first wire semi-finished product obtained in step (2) is alloyed at 50 to 550 ° C., and the second wire semi-finished product composed of a brass core material, an inner layer and an initial outer layer is formed. Is formed, and FIG. 4 shows a cross section thereof.
(4) Powder metallurgy: The second wire semi-finished product obtained in step (3) is subjected to layer coating treatment by powder metallurgy, and is given when the treatment temperature is 300 to 1000 ° C. and the treatment temperature is stable. Within any time interval, the difference between the maximum temperature and the minimum temperature of any point in the work space is 20 ° C or less, and after cooling to 100 ° C or less (within 5 to 30 minutes), brass is removed. A third wire semi-finished product consisting of a core material, an inner layer and an amorphous outer layer is formed, and FIG. 5 shows a cross section thereof.
(5) Stretching to finished product: The third wire semi-finished product obtained in step (4) was subjected to multimode continuous stretching and online stress relaxation annealing, and the stretching speed was 600 to 1500 m / min. Obtained a finished electrode wire with an annealing voltage of 12-60V, an annealing current of 15-50A and a diameter of 0.05-0.25mm, FIG. 2 shows a local cross section of the finished product. There is.

For the electrode wire of the present invention, the tensile strength was tested by a computer-controlled electronic universal tester, and the conductivity was tested by the bridge method.

The electrode wire can be applied to fine electric discharge machining, and can effectively improve the online machining accuracy and surface quality of fine tool electrodes. The causes include the following.

1) Due to the amorphous alloy structure covering the outer surface, the atoms show an irregular arrangement, the resistance is high, the capacitance effect resistance is very high, the high energy emission due to the capacitance effect is greatly reduced, and it is uniform in the discharge process. Can form an electric spark distribution.

2) The amorphous mixed structure reduces the discharge wear of the electrode wire itself, realizes continuous and stable fine discharge corrosion, guarantees that the gap between the electrode wire and the fine tool electrode is constant, and is fine. The surface quality of the tool electrode is improved, the smoothness is high, and minute cracks do not occur.

3) By installing a special relaxation and / or reconstruction structure on the outer surface of the inner layer of the surface layer of the electrode wire, bubbles escape from the relaxation or reconstruction structure based on the theory of surface tension, and the electrode wire and fine particles. It is possible to significantly reduce the direct interference of the instantaneous explosive force with respect to the gap between the tool electrodes, which is advantageous for improving the accuracy of fine electric discharge machining.

4) In the discharge process, the electrode wire itself constantly moves and feeds in one direction, and the fine tool electrode constantly rotates. Therefore, the fact that the electrode wire according to the present invention has a special structure is that the medium has a special structure. Adhesive resistance can be effectively reduced, machining debris can be more easily discharged, and excessive accumulation of galvanic corrosion products in the discharge gap is avoided. Therefore, the occurrence of abnormal discharge is reduced and the quality of the machined surface is improved.

5) The electrode wire has an inner layer made of a β-phase or β'phase copper-zinc alloy, has excellent conductivity, and is advantageous in that fine electric sparks are point-discharged to corrode the tool electrode. ..

6) The main element of the metal in the surface layer of the electrode wire is zinc, which has a very excellent gasification effect, contributes to increasing the discharge efficiency, increases the processing speed, and saves the processing time. can.

7) Since the electrode wire has high tensile strength, product plasticity and toughness, it is convenient for collecting and drawing a small shaft type wire, and the wire is hard to break.

8) Since the electrode wire has high processing accuracy and flexibility, it effectively improves the quality of the processed surface when manufacturing an electrode online by fine electric discharge, and promotes the long-term development of fine electric discharge machining technology. ..

9) The electrode wire meets the requirements for fine electric discharge machining of various complicated shapes based on the actual machining requirements, and is, for example, a cylindrical, conical, prismatic, screw-like, and inclined electrode (multi-axis). It is necessary to arrange an interlocking digital control system), and it is easy to realize automated forming of tool electrodes.

10) The thickness of the altered layer of the electric spark is about 3 to 4 times the Rmax value, and is basically formed by roughing. The roughness value generated by processing with the electrode wire of the present invention is clearly smaller than the roughness value generated by discharging with the brass wire, and the smaller the roughness value, the more the pulse of the electrode wire. Compared to the altered layers of processed materials, because the width is smaller, the duration of current action is shorter, there is not enough time for the amount of heat to be transferred in the depth direction of the material, and the depth at which the amount of heat reaches is relatively small. Thin and long-lasting.

Embodiment 1

The electrode wire for fine electric discharge machining has a diameter D0 of 0.20 mm (here, refers to the diameter of the electrode wire), includes a core material whose material is brass, and a surface layer that covers the outside of the core material, and has a surface surface. The layer consists of an inner layer that covers the outer surface of the core material and an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer consisting of 53.38 wt% Zn, 30.67 wt% Cu, 0.41 wt% Al, 0.87 wt% C, 0.003 wt% Si and 0.002 wt% S. The remaining amount is O. The thickness of the amorphous layer is 5.5 μm, which completely or incompletely covers the structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 50.5 wt% and has a thickness of 10 μm.

The manufacturing process of the electrode wire for fine electric discharge machining is as follows.

(1) A brass bus core material having a diameter of 1.2 mm, a copper content of 62.8 wt%, and a silicon content of 0.01 wt% is produced.

(2) The bus obtained in step (1) is subjected to degreasing, pickling, washing with water and continuous electrozinc plating, and 380 g of zinc sulfate and 25 g of aluminum sulfate are contained in 1 liter of the plating solution. And 13 g of an additive such as polyethylene glycol, arabic rubber, peach resin, dextrin or glucose is added, the thickness of the plating layer is 10 μm, and the first semi-finished wire rod is obtained. The electroplating has a speed of 150 m / min, a current of 1200 A, and a voltage of 150 V.

(3) The first wire wire semi-finished product electroplated in step (2) is placed in a sealed container and evacuated to a vacuum degree of −0.10 MPa. The temperature is 270 ° C., the treatment time is 600 min, and by completing the alloying and chemical segregation reaction between the core material and the plating layer, the material of the inner layer of the electrode wire is obtained, and the elements inside are applied to the surface of the wire semi-finished product. Segregate and obtain a second semi-finished wire rod.

(4) The second wire semi-finished product obtained in the above step (3) was placed in an oxygen atmosphere, the oxygen concentration was set to about 20.9%, the temperature was raised to 550 ° C, and the sintering reaction time was set to 180 min. Temperature fluctuations are controlled within 10 ° C, followed by rapid cooling to room temperature within a time of 30 min using air cooling or water cooling, followed by kiln removal to finally form the required outer layer amorphous material. And acquire the third semi-finished wire rod.

(5) Finally, multimode continuous stretching and online stress relaxation annealing processing were performed on the obtained third wire semi-finished product, the stretching speed was 1000 m / min, the annealing voltage was 32 V, and the annealing current. Is 25A, and a finished product of the electrode wire having a diameter of 0.25 mm is obtained.

Embodiment 2

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer containing 49.5 wt% Zn, 41.5 wt% Cu, 0.61 wt% Fe, 0.78 wt% Ca, 0.002 wt% Si and 0.002 wt% S. Including, the remaining amount is O. The thickness of the amorphous layer is 1 [mu] m, the structure of the inner layer of the outer surface completely or not completely cover. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 50.5 wt% and has a thickness of 5 μm.

Embodiment 3

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer and contains 75.5 wt% Zn, 12 wt% Cu, 0.42 wt% Fe, 0.005 wt% Si and 0.003 wt% P, and the remaining amount is O. The amorphous layer has a thickness of 8 μm and completely or incompletely covers the reconstructed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 46.5 wt% and has a thickness of 40 μm.

Embodiment 4

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer and contains 60.5 wt% Zn, 12.5 wt% Cu, 0.55 wt% C, 0.024 wt% Al and 0.024 wt% B, and the remaining amount is O. be. The thickness of the amorphous layer is 10 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 50.8 wt% and has a thickness of 50 μm.

Embodiment 5

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer containing 71.5 wt% Zn, 11.5 wt% Cu, 0.60 wt% Ca, 0.78 wt% Fe, 0.002 wt% Si and 0.85 wt% C. Including, the remaining amount is O. The thickness of the amorphous layer is 3 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 51.2 wt% and has a thickness of 30 μm.

Embodiment 6

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer containing 74.5 wt% Zn, 1.5 wt% Cu, 0.50 wt% Ca, 2.0 wt% Fe, 2.5 wt% B and 1.6 wt% C. Including, the remaining amount is O. The thickness of the amorphous layer is 7 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 50.5 wt% and has a thickness of 38 μm.

Embodiment 7

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer containing 77.5 wt% Zn, 14.7 wt% Cu, 0.60 wt% Ca, 0.78 wt% Al, 0.002 wt% Si and 0.85 wt% C. Including, the remaining amount is O. The thickness of the amorphous layer is 4 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 50.5 wt% and has a thickness of 25 μm.

8th embodiment

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer and contains 82.5 wt% Zn, 5.2 wt% Cu, 0.50 wt% Al, 0.98 wt% Fe and 0.003 wt% Si, and the remaining amount is O. be. The thickness of the amorphous layer is 9 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 48.5 wt% and has a thickness of 45 μm.

Embodiment 9

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer containing 88.5 wt% Zn, 1.9 wt% Cu, 0.88 wt% Fe, 0.002 wt% B and 0.85 wt% S, and the remaining amount is O. be. The thickness of the amorphous layer is 5 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 50.5 wt% and has a thickness of 30 μm.

Embodiment 10

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer containing 55.5 wt% Zn, 42.5 wt% Cu, 0.05 wt% Ca, 0.1 wt% Fe and 0.008 wt% Si, and the remaining amount is O. be. The thickness of the amorphous layer is 2 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 50.5 wt% and has a thickness of 30 μm.

Embodiment 11

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer and contains 84.5 wt% Zn, 12.5 wt% Cu, 0.60 wt% Ca, 0.08 wt% Si and 0.85 wt% C, and the remaining amount is O. be. The thickness of the amorphous layer is 1 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 50.5 wt% and has a thickness of 25 μm.

Embodiment 12

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer and contains 73.5 wt% Zn, 17.5 wt% Cu, 0.68 wt% Ca, 2.2 wt% Si and 0.8 wt% C, and the remaining amount is O. be. The thickness of the amorphous layer is 6 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 46.5 wt% and has a thickness of 36 μm.

Embodiment 13

The electrode wire for fine electric discharge machining includes a core material having a diameter D0 of 0.20 mm and a material of brass and a surface layer covering the outside of the core material, and the surface layer is an inner layer covering the outer surface of the core material. It consists of an outer layer that covers the outer surface of the inner layer. The outer layer is an amorphous layer and contains 90 wt% Zn, 3.5 wt% Cu, 0.2 wt% Ca, 1.8 wt% Fe and 0.02 wt% Si, and the remaining amount is O. The thickness of the amorphous layer is 7 μm, and completely or incompletely covers the relaxed structure of the outer surface of the inner layer. The inner layer of the electrode wire is made of a β-phase or β'phase copper-zinc alloy having a zinc content of 48.5 wt% and has a thickness of 35 μm.

Comparative example

Comparative Examples 1 and 2 are examples of testing and comparing commercially available red copper wires having a D0 of 0.20 mm when applied to fine electric discharge machining.

Comparative Examples 3, 4, and 5 are examples in which commercially available ordinary brass wires A, B, and C having a D0 of 0.20 mm are tested and compared when applied to fine electric discharge machining.

In Comparative Example 6, the number is 201310562102.8, and the electrode wire for low-speed wire electric spark electric discharge machining and the electrode wire manufactured based on the technical proposal described in the patent which is the manufacturing method thereof are used for fine electric discharge machining. This is an example of testing and comparing when applying.

In Comparative Example 7, the number is 201610795405.8, and the electrode wire for unidirectional wire electric discharge machining and the electrode wire manufactured based on the technical proposal described in the patent which is the manufacturing method thereof are applied to fine electric discharge machining. This is an example of testing and comparing when doing.

<Tensile strength and conductivity>
The finished product of the electrode wire was tested for its tensile strength performance with a computer-controlled electronic universal tester, and its conductivity was tested by the bridge method, and Table 1 shows the results.

表１の各データは、何れも同等の条件でテストして得られ、なお、電極線の直径は何れも０．２０ｍｍである。当然ながら、当業者は、各実施形態の中のコア材の直径、ステップ２、３、４の加工パラメータ及びステップ５のマルチモード連続延伸及びオンライン応力緩和アニーリング加工の条件を有効的に調整することにより、各実施形態の中の完成品の電極線は、直径が０．０５ｍｍ〜０．２５ｍｍの範囲内に変化するようにさせることができる。

Each of the data in Table 1 was obtained by testing under the same conditions, and the diameter of the electrode wire was 0.20 mm. Of course, one of ordinary skill in the art will effectively adjust the diameter of the core material in each embodiment, the machining parameters of steps 2, 3 and 4 and the conditions of multimode continuous stretching and online stress relaxation annealing in step 5. Therefore, the electrode wire of the finished product in each embodiment can be made to change in diameter within the range of 0.05 mm to 0.25 mm.

The tensile strength of the electrode wire for fine electric discharge machining of the present invention in Table 1 is relatively high, the product has good plasticity and toughness, and the conductivity clearly exceeds the level of similar products.

<Fine electric discharge machining test>
The micro discharger to be tested in the test is an SX-100HPM device manufactured by the Swiss SARIX company.

The test conditions are as follows.

The size of the microelectrode to be tested and machined is φ10 μm in diameter (electrode diameter), 150 μm in length, and the material is tungsten copper. The equipment parameters are X / Y / Z / Z 2-axis stroke distance 250X150X150X150 mm, Z-axis feed speed up to 650 mm / min, X, Y-axis feed speed up to 800 mm / min, and resolution 0. It is 1 μm and the cooling mode is 70 bar cooling oil / water high pressure pump.

The fine tool electrodes to be machined are tested for their positioning accuracy with the discharge device SX-100HPM, their shape accuracy (here, roundness) is tested with the laser wire diameter measuring device, and the Mitutoyo roughness measuring device is used. The roughness of the processed surface was tested, and the state of minute cracks on the processed surface was observed with a 200x optical microscope, and Table 2 shows the results.

Each of the data in Table 2 was obtained by testing under the same conditions, and the diameter of the electrode wire was 0.20 mm. Of course, one of ordinary skill in the art will effectively adjust the diameter of the core material in each embodiment, the machining parameters of steps 2, 3 and 4 and the conditions of multimode continuous stretching and online stress relaxation annealing in step 5. Therefore, the electrode wire of the finished product in each embodiment can be made to change in diameter within the range of 0.05 mm to 0.25 mm.

In Table 2, the performance data of the fine tool electrodes obtained by machining with the electrode wires of Embodiments 1 to 13 and the electrode wires of Comparative Examples 1 to 7 are compared, and the electrode wire for fine discharge processing of the present invention is obtained. The fine tool electrode obtained by machining with the electrode wire for fine discharge machining of the present invention has a clear superiority, has higher positioning accuracy and shape accuracy, has better smoothness of the machined surface, and has a machined surface. There are no small cracks in the surface.

1 1st pulse power supply 2 2nd pulse power supply 3 Electrode line 4 Tool electrode 5 Material member 6 Processing liquid 7 Guide 8 Automatic feed adjustment device 301 Core material 302 Inner layer 303 Outer layer 304 Electroplating layer 305 Initial outer layer

Claims (11)

An electrode wire for fine electric discharge machining including a core material whose material is brass and a surface layer that covers the outside of the core material.
The surface layer is an electrode wire for fine electric discharge machining, which includes an inner layer that covers the outer surface of the core material and an outer layer that covers the outer surface of the inner layer and is an amorphous layer. The electrode wire for fine electric discharge machining according to claim 1, wherein the outer surface of the inner layer exhibits a relaxed and / or reconstructed surface structure. The amorphous layer is composed of chemical elements of 49.5 to 90 wt% Zn, 1.5 to 42 wt% Cu and 0.158 to 6.6% X, the remaining amount is O, and X is at least three different. Contains the elements X1, X2, X3, where X1 is Fe, Al or Ca, X2 is Si, C, S or B and X3 is Fe, Al, Ca, Si, C, S or B. The electrode wire for fine discharge processing according to claim 1, wherein the electrode wire is of any one type different from X1 and X2. The electrode wire for fine electric discharge machining according to claim 1, wherein the inner layer is a β-phase or β'phase copper-zinc alloy. The electrode wire for fine electric discharge machining according to claim 1, wherein the amorphous layer completely or incompletely covers the outer surface of the inner layer. The electrode wire for fine electric discharge machining according to claim 1, wherein the amorphous layer has a thickness of 1 to 10 μm, and the inner layer has a thickness of 5 to 50 μm. The core material manufacturing step (1) for forming a brass bus having a diameter of 0.5 to 1.5 mm, and
The bus obtained in step (1) is subjected to degreasing, pickling, washing with water and electroplating to form a zinc-plated layer having a thickness of 0.5 to 50 μm on the bus, and the first wire is formed. Electroplating step (2) to acquire semi-finished products and
The first wire semi-finished product obtained in step (2) is alloyed at 50 to 550 ° C. to form a second wire semi-finished product composed of a brass core material, an inner layer and an initial outer layer. (3) and
The second wire semi-finished product obtained in step (3) is subjected to layer coating treatment by powder metallurgy, the treatment temperature is 300 to 1000 ° C., the temperature fluctuation in the treatment process is within 20 ° C., and 100. A powder metallurgy step (4), which is cooled to a temperature below ℃ and then removed from the kiln to form a third wire semi-finished product composed of a brass core material, an inner layer and an amorphous outer layer.
Multimode continuous stretching and online stress relaxation annealing are performed on the third wire semi-finished product obtained in step (4) to obtain a finished electrode wire with a diameter of 0.05 to 0.25 mm. A method for manufacturing an electrode wire for fine electric discharge machining, which comprises a stretching step (5) to a product. The chemical components of the electroplating solution of step (2) are carbon, nitrogen, oxygen and hydrogen having a total concentration of 0.1 to 400 g / L and boron having a total concentration of 0.5 to 600 g / L. , Sulfur, chlorine, aluminum having a concentration of 1.2 to 1000 g / L, and zinc having a concentration of 100 to 1500 g / L, and the electroplating in step (2) has a speed of 10 to 500 m / L. The method for manufacturing an electrode wire for fine electric discharge machining according to claim 7, wherein the electrode wire is min, the current is 1200 to 2500 A, and the voltage is 120 to 220 V. The method for manufacturing an electrode wire for fine electric discharge machining according to claim 7, wherein the cooling time in step (4) is 5 to 30 minutes. The fineness according to claim 7, wherein in the step (5), the stretching speed is 600 to 1500 m / min, the annealing voltage is 12 to 60 V, and the annealing current is 15 to 50 A. A method for manufacturing electrode wires for electric discharge machining. The electrode wire is the electrode wire according to any one of claims 1 to 6, and is an application of the electrode wire for fine electric discharge machining, which is used for fine electric discharge machining.

Images