JP2017030134A - Electrode wire having high performance and low consumption for electric discharge corrosion processing and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode wire with high performance and low consumption for electric discharge corrosion processing which has high cut efficiency, low consumption and high accuracy.SOLUTION: An electrode wire includes a core material 1 and a shell layer. A construction material of the core material is copper or a copper alloy, and a construction material of the shell layer is zinc or a zinc alloy. The shell layer includes a shell layer base part 2 which covers a surface of the core material, an electrode point 4, and a protective layer 5 which covers a surface of the shell layer base part, the electrode point comprises an electrode fine particle embedded into the shell layer base part, and the electrode fine particle comprises aggregation of an electronic compound of a large quantity of copper-zinc alloys. The shell layer base part is provided with a passage 3 around the electrode point and/or at a central part thereof, and the passage has a fine hole shape and a hole diameter of not less than 100 nm and not more than 1000 nm.SELECTED DRAWING: Figure 4

Description

  The present invention relates to the field of electric discharge corrosion processing, and more particularly to an electrode wire for electric discharge corrosion processing with high efficiency and low consumption and a method for manufacturing the same.

  Wire Cut Electrical Discharge Machining (abbreviated as WEDM, WC) is also known as wire cutting. It uses pulsed discharge corrosion on a workpiece by using a thin wire (referred to as electrode wire) that moves continuously as an electrode. It is a processing method that finishes the workpiece by removing and cutting.

  The physical principle of wire cut electric discharge machining is as follows. The work to be cut is used as a work electrode, and the fine wire (that is, the electrode wire) is used as a tool electrode. In order to generate a spark between the two electrodes, the voltage applied to it must be higher than the breakdown voltage of GAP (the gap between the electrode line and the workpiece). A strong electric field is formed at the beginning of this process, and the highest concentration of positive and negative ions is formed at the portion where the electrode wire and the workpiece are closest to each other. Due to the action of the strong electric field, electrons and cations are accelerated and reach a high velocity, and an ion path for electrical conduction is formed quickly. At this time, a spark is generated between both electrodes (electrode wire and workpiece) by current. As a result, a plasma area is formed by causing an extremely large number of collisions between particles. At the same time, bubbles are formed by the evaporation of the “electrode” and the machining liquid, and the pressure rises to a high value, so that the already formed plasma area immediately reaches an extremely high temperature of 8000 ° C. to 12000 ° C. As the number of collisions continues to increase and reach high temperatures, a certain amount of material instantly partially melts on the surfaces of both conductors. When the current is cut off, a sudden drop in temperature causes an explosion of bubbles, and the generated power releases the melted material from the discharge pits, and the removed material immediately enters the working fluid. It condenses into small spheres and is discharged as sludge by the machining fluid. During the machining process, the removal amount of the electrode and the workpiece is not the same, but these are mainly determined by the polarity of the electrode, the thermal conductivity of the material, the melting point, the duration and strength of the discharge, the wire travel speed, etc. The removal generated in step is consumed, and the removal generated in the workpiece is used as the material removal amount.

  In the process of wire cut electric discharge machining, it is desirable that the amount of wear generated in the electrode wire is as small as possible. This is because the electrode wire is a long wire to be moved, and in the same cut area, the less the electrode wire is consumed per unit length, the lower the energy consumption and the more electrode wires that can be reused. This is because the degree of contamination with respect to the environment becomes small, and a clean and ecological low consumption wire cut can be realized. At present, the method of reducing electrode wear by using the polarity effect (the tool electrode is connected to the cathode during finishing and vice versa during roughing) is often used. 201010102045.1 (Application Publication Number CN101829822A) Chinese Invention Patent “A kind of micro-sparking tool electrode wear-reducing method for reducing the size of secondary sparks between secondary electrodes” In the method for reducing electrode wear), a diode is forward-biased by connecting a fast switching diode or an ultrafast recovery diode to a part closest to the tool electrode or workpiece, and the diode, the electrode and the pulse power source 3 A person can form a series circuit to significantly reduce the consumption of the tool electrode in micro-EDM. However, at present, it is not yet known to reduce the consumption in the electric discharge corrosion processing by improving the electrode wire itself.

  The first technical problem to be solved by the present invention is to provide a high-efficiency and low-consumption electrode wire for high-efficiency and low-consumption, which has high cutting efficiency and low consumption as well as high accuracy over the prior art. That is.

  The second technical problem to be solved by the present invention is to provide a method for manufacturing the above-described electrode wire with respect to the prior art.

  The present invention starts from the electrode wire itself, and the electrode wire realizes quick discharge cut and metal corrosion by the electrode point, and is provided around the electrode point and / or near the inside of the center of the electrode wire. Improve the direction in which the explosive force of the bubbles pops out through the passage so that the removed material can be expelled from both sides of the discharge pit quickly, and contact with the center of the electrode line to generate secondary discharge. By preventing and protecting the electrode wire, consumption of the electrode wire is reduced.

  The technical solution adopted by the present invention to solve the first technical problem includes a core material made of Cu or a copper alloy and a shell layer made of Zn or a zinc alloy. An electrode wire for electric discharge corrosion machining with low efficiency and low consumption, wherein the shell layer includes a shell layer base that covers the surface of the core, an electrode point, and a protective layer that covers the surface of the shell layer base. The electrode point is an electrode fine particle embedded in the shell layer base, and the electrode fine particle is composed of a large amount of a copper-zinc alloy electronic compound, and the shell layer base includes a portion around the electrode point and In addition, a passage extending from the inside to the outside is distributed in the central portion of the shell layer base portion, and the passage has a micropore shape and has a pore diameter of 100 nm or more and 1000 nm or less.

  Preferably, the composition of the percentage by mass of each component in the shell layer is such that Zn is 42.5 to 52.5%, the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less It is. By setting the content of zinc, the vaporization performance at the time of cut discharge can be enhanced, which helps to increase the surface smoothness of the cut workpiece.

  The thickness of the shell layer in the present invention is 10-50 μm, and also has a good conductivity of 22-25% IACS, the shell layer base of the shell layer is relatively excellent in toughness, the process of cut discharge Thus, disconnection of the electrode wire caused by lack of toughness can be avoided. In addition, the shell layer base portion has a good conductive performance, and can further effectively transmit discharge energy to increase the cutting efficiency.

  Preferably, the particle size of the electrode points is 200 to 2000 nm, and the ratio of the electrode points to the shell layer base is 20 to 80%. Further, 80% of the electrode points are annularly distributed around the core material and are uniformly distributed outside the core material. As described above, the electrode point is an electrode fine particle embedded in the shell layer base, and the electrode fine particle is composed of a large amount of an electronic compound of a copper-zinc alloy, and the electrons have a relatively small mass and inertia. , Relatively large acceleration and velocity can be easily obtained, fly at high speed toward the anode in the initial stage of breakdown discharge, transfer energy to the anode surface of the workpiece, and quickly melt and vaporize the electrode point Has excellent discharge effect, and can realize quick discharge cut and metal corrosion.

Preferably, the electronic compound of the copper zinc alloy is at least one of CuZn, Cu ₃ Zn ₂ , and Cu ₅ Zn ₈ .

  Preferably, the composition of the mass percent of each component in the core material is 58.5 to 68.5% Cu, the remainder is inevitable impurities accompanying Zn and raw materials, the sum of the contents of inevitable impurities is 0.3% or less It is.

  The technical solution adopted by the present invention to solve the second technical problem is as follows.

  (1) Manufacture of core material: Cu or copper alloy is pulled to produce a bus bar having a wire diameter of Φ0.6 to Φ1.5 mm. The tensile strength is 400 to 600 MPa, the Cu content in the copper alloy is 58.5 to 68.5%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less.

  (2) Manufacture of shell layer base: A first wire blank is obtained by coating the bus bar manufactured above with one layer of Zn or zinc alloy having a thickness of 10 to 50 μm to form a shell layer base. Among the zinc alloys, the Zn content is 42.5 to 99%, the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the inevitable impurity content is 0.3% or less. The shell layer base has a hardness of HB 20-50, a cross-sectional shrinkage of 60% or more, and a conductivity of 22-25% IACS. Since the shell layer base at this time has a relatively low hardness, it is easy to form electrode points by embedding electrode fine particles in step (3), and has good plasticity and toughness and cold work performance, It is convenient to uniformly distribute the electrode fine particles in a ring shape at the base of the shell layer in the process of processing the electrode wire.

  (3) Formation of electrode points and passages: The first wire blank is subjected to heat treatment and press processing so as to obtain desired electrode points and passages in the shell layer base, and a semi-finished electrode wire is obtained. . The parameters of the heat treatment are a heat treatment temperature of 400 to 500 ° C., a heat treatment time of 2 to 10 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 500-1500 m / min, a processing voltage of 10-50 V, a current of 5-20 A, and a processing rate of 82.6-97.2%.

  (4) Production of protective layer: Passive treatment and dry treatment are performed on the semi-finished electrode wire produced above to form a protective layer having a thickness of 0.1 to 0.5 μm. The dry temperature is 50 to 100 ° C., and the final wire diameter of the electrode wire finally obtained is Φ0.2 to Φ0.35 mm. When the protective layer having a uniform thickness is formed by the passivation treatment and the dry treatment, the performance of the electrode wire is stabilized and the conductivity of the electrode wire can be increased. Since the protective layer effectively prevents the electrode line from being oxidized, the storage period of the electrode line can be extended. In addition, the passivating process and the dry process used are performed at the same time as the pressing process for continuous tension and continuous annealing, so the production process is simple, feasible, the number of manufacturing steps is small, and the production equipment is simple. Therefore, it has a significant advantage of low cost.

  Compared with the prior art, the advantages of the present invention are as follows.

  (1) The electrode point is an electrode fine particle embedded in the shell layer base, and the electrode fine particle is composed of a large amount of an electronic compound of a copper zinc alloy. As derived from the kinetic energy equation, electrons have a relatively small mass and inertia, so they can obtain large accelerations and velocities, fly at high speed toward the anode in the early stages of breakdown discharge, and work energy. The electrode point has an excellent discharge effect, and rapid discharge cut and metal corrosion can be realized. In addition, the surface area of the electrode wire increases due to the passage in the shell layer and the dent left after the zinc is corroded and removed, and the heat dissipation area during discharge increases due to the increase in the surface area. The gathering energy is more easily dispersed, and thus the cutting speed of the electrode wire is remarkably improved.

  (2) When the current is cut off, an explosion of bubbles occurs due to a sudden drop in temperature, and the generated power releases molten material from the discharge pit, but a large amount of gas is accumulated in the passage. Since it has a buffering effect on the material released from the front side of the discharge pit and even generates a reaction force, when the equipment is washed with high pressure water, the corroded material is released from both sides of the electrode wire, Prevents the secondary discharge from occurring due to contact with the core of the electrode wire, protects the electrode wire, and reduces the consumption of the electrode wire. In addition, the passage reduces the ion velocity, and the discharge can be terminated before the number of ions reaching the cathode of the electrode wire reaches the maximum value, so that the bombing action on the electrode wire is reduced and the electrode wire is consumed. Is further reduced.

  (3) The passage in the shell layer of the present invention further cuts off the continuity of copper zinc, which is the metal of the shell layer, to ensure the interval between discharges at the time of cutting. It plays the role of cooling and chip removal. At the time of discharge, since zinc has a low melting point and low evaporation enthalpy, it is first removed by corrosion, but copper oxide, cuprous oxide, zinc suboxide, etc. having a high melting point remain on the surface of the electrode wire. Therefore, the consistency of the geometric shape of the electrode wire is ensured, and the consistency of the geometric shape of the electrode wire contributes to increase the geometric tolerance and dimensional accuracy of the cut workpiece. It has become.

It is a cross-sectional schematic diagram of the bus-line in Example 1 of this invention. It is a cross-sectional schematic diagram of the 1st line blank in Example 1 of this invention. It is a cross-sectional schematic diagram of the semi-finished product of the electrode wire in Example 1 of this invention. It is a cross-sectional schematic diagram of the finished product of the electrode wire in Example 1 of this invention. FIG. 4 is an enlarged view of a portion I in FIG. 3. It is an enlarged view of the II part of FIG. It is a microscope picture figure (x100) of the cross section of the bus-line in Example 1 of this invention. It is a microscope picture figure (x100) of the cross section of the 1st line blank in Example 1 of this invention. It is a microscope picture figure (x100) of the cross section of the semifinished product of the electrode wire in Example 1 of this invention. It is a microscope picture figure (x100) of the cross section of the finished product of the electrode wire in Example 1 of this invention. It is an electron microscope figure (x300) of the cross section of the finished product of the electrode wire by Example 1 of this invention. It is an electron microscope figure (x2000) of a part of cross section of the finished product of the electrode line by Example 1 of the present invention.

  Hereinafter, the present invention will be described in more detail with reference to the drawings and examples.

<Example 1>
As shown in FIGS. 1 to 6, a copper wire blank is tensioned to produce a bus bar with a diameter of Φ0.6 mm under a tensile strength of 400 MPa. Subsequently, the first bus blank is obtained by electroplating the obtained bus bar to coat a single layer of zinc alloy having a thickness of 10 μm to form the shell layer base 2. The core material 1 is comprised from said bus-bar among the said 1st line blanks. The zinc alloy has a Zn content of 42.5%, the remainder being inevitable impurities associated with Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. Thereafter, the first wire blank is subjected to heat treatment and press working to obtain a semi-finished electrode wire. In the processing process, the elements in the shell layer base 2 are again distributed and diffused to form an electronic compound of a copper-zinc alloy. Electrode fine particles are formed by the assembly of the electronic compounds of the copper-zinc alloy to form electrode points 4, and the passages extend from the inside along the shell layer base 2 around the electrode points and / or at the center of the shell layer base 2. 3 is formed. The heat treatment parameters are as follows: the heat treatment temperature is 400 ° C., the heat treatment time is 2 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 500 m / min, a processing voltage of 10 V, a current of 5 A, and a processing rate of 89.6%. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer 5 having a thickness of 0.1 μm, thereby manufacturing a finished product of the electrode wire. The protective layer 5 can prevent the electrode wire from being oxidized and extend the storage period of the electrode wire. The dry temperature is 50 ° C., and the final electrode wire diameter obtained is Φ0.2 mm.

  7 to 12 are photographs of raw materials, semi-finished products and finished products in this example. It can be seen from FIG. 7 that the internal structure of the busbar is homogeneous. A first wire blank is formed by covering the bus bar with a zinc alloy layer (see FIG. 8). When heat treatment and press processing are performed, diffusion occurs in the core material and the plating layer, and the shell layer is formed by reducing the diameter of the core material and increasing the thickness of the plating layer. The electrode points and the passages are formed by distributing and diffusing again on the surface (see FIGS. 9 to 12). The manufactured electrode wire forms a core material by the above busbar, and the content of Cu in the core material is 58.5%. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this example, the thickness of the shell layer is 10 μm, the hardness of the shell layer base is HB20, the cross-sectional shrinkage is 80%, and the conductivity is 22% IACS. The base of the shell layer has a relatively low hardness, and it is easy to form electrode points by embedding electrode fine particles, and has good plasticity and toughness and cold work performance. Contributes to uniform distribution in a ring shape at the base of the shell layer. In addition to avoiding the disconnection caused by insufficient toughness of the electrode wire in the discharge cutting process, the shell layer base has good conductive performance, so that the discharge energy is transmitted more effectively and the cutting efficiency is improved. Can be increased.

The electrode points are embedded in the shell layer base, and the proportion of the electrode points in the shell layer base is 60%, and 80% of the electrode points are distributed annularly around the core material and uniformly distributed outside the core material. The electrode point is an electrode fine particle, the average particle diameter is 200 nm, is composed of a large amount of an electronic compound of CuZn, and exists in the shell layer base in the form of an ordered solid solution based on Cu ₃ Zn and Cu ₉ Zn. To do. According to the kinetic energy formula E _k = mv ^2/2, the total kinetic energy E _k is unchanged, if electron mass (m) is relatively small, resulting acceleration and velocity (v) for also increases the yield It flies at high speed toward the anode in the initial stage of discharge, and energy is transferred to the anode surface of the workpiece. By rapidly melting and vaporizing it, the electrode point has an excellent discharge effect, and a quick discharge cut and metal corrosion can be realized. In addition, in the shell layer base, passages are distributed around the electrode points and / or in the center of the shell layer base, the passages are microporous, and the average pore diameter is 1000 nm. When the current is cut off, the explosion of bubbles is caused by a sudden drop in temperature, and the generated power releases molten material from the discharge pit, but a large amount of gas is accumulated in the passage. Because the material released from the front side of the discharge pit has a buffering action and even generates a reaction force, when the equipment is washed with high pressure water, the corroded material is released from both sides of the electrode wire, It prevents the secondary discharge from occurring due to contact with the core of the electrode wire, protects the electrode wire, and reduces the consumption of the electrode wire. In addition, the passage reduces the ion velocity, and the discharge can be terminated before the number of ions reaching the cathode of the electrode wire reaches the maximum value, so that the bombing action on the electrode wire is reduced and the electrode wire is consumed. Is further reduced.

<Example 2>
A copper alloy wire blank is tensioned to produce a bus bar with a diameter of Φ1.5mm under a tensile strength of 600MPa. The content of Cu in the bus bar is 68.5%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. Subsequently, a first wire blank is obtained by coating the obtained bus bar with a single layer of zinc alloy having a thickness of 50 μm by hot dipping to form a shell layer base. The zinc alloy has a Zn content of 52.5%, and the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. Thereafter, the first wire blank is subjected to heat treatment and press working to obtain a semi-finished electrode wire. The heat treatment parameters are as follows: the heat treatment temperature is 500 ° C., the heat treatment time is 10 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 1500 m / min, a processing voltage of 50 V, a current of 20 A, and a processing rate of 95.2%. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer having a thickness of 0.5 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 100 ° C., and the final diameter of the final electrode wire is Φ0.35 mm.

  The manufactured electrode wire forms a core material by the above-described bus bar. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this example, the thickness of the shell layer is 50 μm, the hardness of the shell layer base is HB50, the cross-sectional shrinkage is 61%, and the conductivity is 25% IACS.

The electrode points are embedded in the shell layer base, and the proportion of the electrode points in the shell layer base is 20%, and 80% of the electrode points are distributed in a ring shape around the core material and uniformly distributed outside the core material. Yes. The electrode point is an electrode fine particle having an average particle diameter of 2000 nm, consisting of a large amount of an electronic compound of Cu ₃ Zn ₂ , and a shell layer base in the form of an ordered solid solution based on Cu ₃ Zn and Cu ₉ Zn. Present in. In addition, in the shell layer base, passages are distributed around the electrode points and / or in the center of the shell layer base, the passages are microporous, and the average pore diameter is 800 nm.

<Example 3>
A copper alloy wire blank is tensioned to produce a bus bar with a diameter of Φ0.8mm under a tensile strength of 500MPa. The Cu content in the bus bar is 60.5%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. Subsequently, a first wire blank is obtained by coating the obtained busbar with a single layer of a zinc alloy having a thickness of 25 μm by spraying to form a shell layer base. In the zinc alloy, the Zn content is 49.5%, and the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the inevitable impurity content is 0.3% or less. Thereafter, the first wire blank is subjected to heat treatment and press working to obtain a semi-finished electrode wire. The heat treatment parameters are as follows: the heat treatment temperature is 450 ° C., the heat treatment time is 6 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 1000 m / min, a processing voltage of 30 V, a current of 12 A, and a processing rate of 87.5%. Finally, the semi-finished electrode wire manufactured above is subjected to passivation treatment and dry treatment to form a protective layer having a thickness of 0.3 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 75 ° C., and the wire diameter of the final electrode wire finally obtained is Φ0.30 mm.

  The manufactured electrode wire forms a core material by the above-described bus bar. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this example, the thickness of the shell layer is 25 μm, the hardness of the shell layer base is HB35, the cross-sectional shrinkage is 65% or more, and the conductivity is 23% IACS.

The electrode points are embedded in the shell layer base, and the proportion of the electrode points in the shell layer base is 80%, and 80% of the electrode points are annular around the core material and uniform on the outside of the core material . The electrode point is an electrode fine particle, the average particle diameter is 600 nm, and is composed of a large amount of an electronic compound of Cu ₅ Zn ₈ , and the shell layer base in the form of an ordered solid solution based on Cu ₃ Zn and Cu ₉ Zn. Present in. In addition, in the shell layer base, passages are distributed around the electrode points and / or around the center of the shell layer base, the passages are microporous, and the average pore diameter is 1000 nm.

<Example 4>
A copper alloy wire blank is tensioned to produce a bus bar with a diameter of Φ0.7mm under a tensile strength of 450MPa. The content of Cu in the bus bar is 62.5%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. Subsequently, a first wire blank is obtained by coating the obtained bus bar with a single layer of zinc having a thickness of 30 μm by electroplating to form a shell layer base. Thereafter, the first wire blank is subjected to heat treatment and press working to obtain a semi-finished electrode wire. The heat treatment parameters are as follows: the heat treatment temperature is 480 ° C., the heat treatment time is 5 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 700 m / min, a processing voltage of 25 V, a current of 10 A, and a processing rate of 89.2%. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer having a thickness of 0.4 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 60 ° C., and the wire diameter of the final electrode wire finally obtained is Φ0.25 mm.

  The manufactured electrode wire forms a core material by the above-described bus bar. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this example, the content of Zn in the shell layer is 48.5%, the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. The thickness of the shell layer is 30 μm, the hardness of the shell layer base is HB30, the cross-sectional shrinkage is 70%, and the conductivity is 24% IACS.

The electrode points are embedded in the shell layer base, and the proportion of the electrode points in the shell layer base is 60%, and 80% of the electrode points are distributed in a ring shape around the core material and uniformly distributed outside the core material. Yes. The electrode point is an electrode fine particle having an average particle diameter of 1200 nm, consisting of a large amount of an assembly of CuZn and Cu ₃ Zn ₂ electronic compounds, and in the form of an ordered solid solution based on Cu ₃ Zn and Cu ₉ Zn. Present in the base of the layer. In addition, in the shell layer base, passages are distributed around the electrode points and / or in the center of the shell layer base, the passages are microporous, and the average pore diameter is 600 nm.

<Example 5>
The copper wire blank is tensioned to produce a bus bar with a diameter of Φ1.0mm under a tensile strength of 550MPa. Subsequently, the obtained bus bar is coated with a single layer of zinc having a thickness of 35 μm by a spraying method to form a shell layer base, thereby obtaining a line blank. Thereafter, the above-mentioned wire blank is subjected to heat treatment and press processing to obtain a semi-finished electrode wire. The parameters of the heat treatment are a heat treatment temperature of 480 ° C., a heat treatment time of 4 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 1000 m / min, a processing voltage of 35 V, a current of 18 A, and a processing rate of 90.5%. Finally, the semi-finished electrode wire manufactured above is subjected to passivation treatment and dry treatment to form a protective layer having a thickness of 0.3 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 55 ° C, and the final wire diameter of the final electrode wire is Φ0.33mm.

  The manufactured electrode wire forms a core material from the above busbar, and the content of Cu in the core material is 65.5%. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this example, Zn in the shell layer is 50.0%, the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. The thickness of the shell layer is 30 μm, the hardness of the shell layer base is HB25, the cross-sectional shrinkage is 75%, and the conductivity is 25% IACS.

The electrode points are embedded in the shell layer base, and the ratio of the electrode points to the shell layer base is 75%, and 80% of the electrode points are distributed in a ring shape around the core material and evenly distributed outside the core material. Yes. Electrode points are electrode fine particles with an average particle diameter of 1700 nm, consisting of a large amount of CuZn electronic compounds, and existing in the shell layer base in the form of ordered solid solutions based on Cu ₃ Zn and Cu ₉ Zn. To do. In addition, in the shell layer base, passages are distributed around the electrode points and / or in the center of the shell layer base, the passages are microporous, and the average pore diameter is 400 nm.

<Example 6>
A copper alloy wire blank is tensioned to produce a bus bar with a diameter of Φ1.2mm under a tensile strength of 500MPa. The content of Cu in the bus bar is 61.5%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. Subsequently, a single blank zinc alloy having a thickness of 40 μm is coated on the obtained bus bar by a hot dipping method to form a shell layer base, thereby obtaining a line blank. The zinc alloy has a Zn content of 52.5%, and the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. Thereafter, the wire blank is heat-treated and pressed to obtain a semi-finished electrode wire. The parameters of the heat treatment are a heat treatment temperature of 480 ° C., a heat treatment time of 8 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 1200 m / min, a processing voltage of 40 V, a current of 15 A, and a processing rate of 94.5%. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer having a thickness of 0.4 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 80 ° C., and the final diameter of the final electrode wire is Φ0.3 mm.

  The manufactured electrode wire forms a core material by the above-described bus bar. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this example, the thickness of the shell layer is 40 μm, the hardness of the shell layer base is HB30, the cross-sectional shrinkage is 80%, and the conductivity is 23% IACS.

The electrode points are embedded in the shell layer base, and the ratio of the electrode points to the shell layer base is 45%, and 80% of the electrode points are provided annularly around the core material and evenly provided outside the core material. Yes. The electrode point is an electrode fine particle having an average particle diameter of 1000 nm, consisting of a large amount of an electronic compound of Cu ₃ Zn ₂ and Cu ₅ Zn ₈ , and an ordered solid solution based on Cu ₃ Zn and Cu ₉ Zn. Present in the shell layer base in form. In addition, in the shell layer base, passages are distributed around the electrode points and / or in the center of the shell layer base, the passages are microporous, and the average pore diameter is 600 nm.

<Example 7>
The copper alloy wire blank is tensioned to produce a bus bar with a wire diameter of Φ1.3mm under a tensile strength of 550MPa. The Cu content in the bus bar is 63.0%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. Subsequently, the obtained bus bar is coated with a zinc alloy layer having a thickness of 20 μm by a hot dipping method to form a shell layer base, thereby obtaining a wire blank. The zinc content of the zinc alloy is 46.5%, and the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. Thereafter, the above-mentioned wire blank is subjected to heat treatment and press processing to obtain a semi-finished electrode wire. The parameters of the heat treatment are a heat treatment temperature of 480 ° C., a heat treatment time of 8 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 700 m / min, a processing voltage of 30 V, a current of 18 A, and a processing rate of 96.5%. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer having a thickness of 0.2 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 60 ° C., and the wire diameter of the final electrode wire finally obtained is Φ0.25 mm.

  The manufactured electrode wire forms a core material by the above-described bus bar. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this example, the thickness of the shell layer is 20 μm, the hardness is HB30, the cross-sectional shrinkage is 70%, and the conductivity is 23% IACS.

The electrode points are embedded in the shell layer base, and the ratio of the electrode points to the shell layer base is 70%, and 80% of the electrode points are distributed in an annular shape around the core material and evenly distributed outside the core material. Yes. The electrode point is an electrode fine particle, the average particle diameter is 1200 nm, and is composed of a large amount of an electronic compound of CuZn and Cu ₃ Zn ₂ and Cu ₅ Zn ₈ , and is based on Cu ₃ Zn and Cu ₉ Zn. Present in the shell layer base in the form of a solid solution. In addition, in the shell layer base, passages are distributed around the electrode points and / or in the center of the shell layer base, the passages are microporous, and the average pore diameter is 100 nm.

  About the electrode wire for electric discharge corrosion processing with high efficiency and low consumption manufactured finally in Examples 1 to 7, the overall mechanical properties were tested with a universal electronic extensometer. The electrical conductivity was tested by the bridge method, and the electrical discharge machining speed and the amount of wear of the high-efficiency, low-consumption electrode wire manufactured using the high-quality carbon steel S45C with a thickness of 60 mm as a workpiece were tested. As shown in 1.

<Comparative Example 1>
A copper alloy wire blank is tensioned to produce a bus bar with a diameter of Φ1.5mm under a tensile strength of 600MPa. The content of Cu in the bus bar is 68.5%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. Subsequently, a first wire blank is obtained by coating the obtained bus bar with a single layer of zinc alloy having a thickness of 50 μm by hot dipping to form a shell layer base. The zinc alloy has a Zn content of 52.5%, and the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. Thereafter, the first wire blank is repeatedly continuously pulled and subjected to continuous annealing to obtain a semi-finished electrode wire. The tensile speed is 1000m / min, the annealing voltage is 50V, and the annealing current is 30A. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer having a thickness of 0.5 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 100 ° C., and the final diameter of the final electrode wire is Φ0.35 mm.

  The manufactured electrode wire forms a core material by the above-described bus bar. The shell layer outside the core material includes a shell layer base and a protective layer. In this comparative example, the thickness of the shell layer is 50 μm, the hardness is HB50, the cross-sectional shrinkage is 61%, and the conductivity is 25% IACS.

<Comparative example 2>
The copper wire blank is tensioned to produce a bus bar with a diameter of Φ1.6mm under a tensile strength of 550MPa. Subsequently, a first wire blank is obtained by coating the obtained bus bar with a single layer of zinc alloy having a thickness of 35 μm by spraying to form a shell layer base. Thereafter, the first wire blank is subjected to heat treatment and press working to obtain a semi-finished electrode wire. Regarding the heat treatment parameters, the heat treatment temperature is 660 ° C., the heat treatment time is 20 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 1000 m / min, a processing voltage of 35 V, a current of 18 A, and a processing rate of 97.8%. Finally, the semi-finished electrode wire manufactured above is subjected to passivation treatment and dry treatment to form a protective layer having a thickness of 0.3 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 55 ° C., and the final diameter of the final electrode wire is Φ0.25 mm.

The produced electrode wire forms a core material by the above busbar, the Cu content in the core material is 65.5%, the remainder is inevitable impurities accompanying Zn and raw materials, the content of inevitable impurities Is less than 0.3%. The shell layer outside the core material includes a shell layer base and a protective layer. In this comparative example, the Zn content in the shell layer is 51.5%, the remainder is inevitable impurities accompanying Cu and raw materials, and the sum of the inevitable impurity contents is 0.3% or less. The thickness of the shell layer is 35 μm, the hardness is HB25, the cross-sectional shrinkage is 75%, and the conductivity is 25% IACS. The electrode points are embedded in the shell layer base, and the ratio of the electrode points to the shell layer base is 75%, and 80% of the electrode points are provided annularly around the core material and evenly provided outside the core material. Yes. Electrode points are electrode fine particles with an average particle diameter of 1700 nm, consisting of a large amount of CuZn electronic compounds, and existing in the shell layer base in the form of ordered solid solutions based on Cu ₃ Zn and Cu ₉ Zn. To do.

<Comparative Example 3>
A copper wire blank is pulled to produce a bus bar with a diameter of Φ1.2mm under a tensile strength of 600MPa. Subsequently, a first wire blank is obtained by coating the obtained bus bar with a single layer of a 30 μm thick zinc alloy by spraying to form a shell layer base. Thereafter, the first wire blank is subjected to heat treatment and press working to obtain a semi-finished electrode wire. The heat treatment parameters are a heat treatment temperature of 200 ° C., a heat treatment time of 2 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 1000 m / min, a processing voltage of 35 V, a current of 18 A, and a processing rate of 96.1%. Finally, the semi-finished electrode wire manufactured above is subjected to passivation treatment and dry treatment to form a protective layer having a thickness of 0.3 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 55 ° C., and the final diameter of the final electrode wire is Φ0.25 mm.

  The manufactured electrode wire forms a core material by the above busbar, the content of Cu in the core material is 62.5%, the remainder is inevitable impurities accompanying Zn and raw materials, the content of inevitable impurities The sum is 0.3% or less. The shell layer outside the core material includes a shell layer base and a protective layer. In this comparative example, the Zn content in the shell layer is 48.5%, the remainder is inevitable impurities associated with Cu and raw materials, and the sum of the inevitable impurity contents is 0.3% or less. The thickness of the shell layer is 30μm, the hardness is HB25, the cross-sectional shrinkage is 75%, the conductivity is 25% IACS, and the passage is distributed around the electrode point at the base of the shell layer. The average diameter of the pores is 800 nm.

<Comparative example 4>
A copper wire blank is pulled to produce a bus bar with a diameter of Φ0.5mm under a tensile strength of 400MPa. Subsequently, a single blank zinc alloy having a thickness of 10 μm is coated on the obtained bus bar by electroplating to form a shell layer base, thereby obtaining a line blank. The zinc alloy has a Cu content of 47.5%, the remainder being inevitable impurities associated with Zn and raw materials, and the sum of the inevitable impurity content is 0.3% or less. Thereafter, the above-mentioned wire blank is subjected to heat treatment and press processing to obtain a semi-finished electrode wire. The heat treatment parameters are a heat treatment temperature of 600 ° C. and a heat treatment time of 1 hour, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 500 m / min, a processing voltage of 10 V, a current of 5 A, and a processing rate of 76.9%. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer having a thickness of 0.1 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 50 ° C., and the wire diameter of the final electrode wire finally obtained is Φ0.25 mm.

The produced electrode wire forms a core material by the above busbar, the Cu content in the core material is 58.5%, the remainder is inevitable impurities accompanying Zn and raw materials, the content of inevitable impurities Is less than 0.3%. The shell layer outside the core material includes a shell layer base and a protective layer. In this comparative example, the thickness of the shell layer is 10 μm, the hardness is HB20, the cross-sectional shrinkage is 80%, and the conductivity is 22% IACS. The electrode points are embedded in the shell layer base, and the proportion of the electrode points in the shell layer base is 20%, and 80% of the electrode points are provided annularly around the core material and evenly on the outside of the core material. The electrode points are electrode fine particles having an average particle size of 200 nm, consisting of a large amount of an electronic compound of CuZn, and in the form of an ordered solid solution based on Cu ₃ Zn and Cu ₉ Zn in the shell layer base. Exists.

<Comparative Example 5>
The copper alloy wire blank is tensioned to produce a bus bar with a wire diameter of Φ1.5mm under a tensile strength of 500MPa. The Cu content in the bus bar is 60.5%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. Subsequently, a first wire blank is obtained by coating the obtained bus bar with a 35 μm thick zinc alloy by a hot dipping method to form a shell layer base. In the zinc alloy, the content of Cu is 52.5%, and the remainder is inevitable impurities accompanying Zn and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. Thereafter, the first wire blank is subjected to heat treatment and press working to obtain a semi-finished electrode wire. The heat treatment parameters are as follows: heat treatment temperature is 450 ° C., heat treatment time is 5 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 1200 m / min, a processing voltage of 40 V, a current of 15 A, and a processing rate of 98.4%. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer having a thickness of 0.4 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 80 ° C., and the final diameter of the final electrode wire is Φ0.2 mm.

  The manufactured electrode wire forms a core material by the above-described bus bar. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this comparative example, the thickness of the shell layer is 35 μm, the hardness is HB30, the cross-sectional shrinkage is 80%, and the conductivity is 23% IACS.

The electrode points are embedded in the shell layer base, and the ratio of the electrode points to the shell layer base is 70%, and 80% of the electrode points are embedded in the core material with the core material as the center. The electrode point is an electrode fine particle having an average particle diameter of 1700 nm, consisting of a large amount of an electronic compound of Cu ₃ Zn ₂ and Cu ₅ Zn ₈ , and an ordered solid solution based on Cu ₃ Zn and Cu ₉ Zn. Present in the shell layer base in form. In addition, in the shell layer base, passages are distributed around the electrode points, the passages are microporous, and the average pore diameter is 600 nm.

<Comparative Example 6>
A copper alloy wire blank is tensioned to produce a bus bar with a diameter of Φ0.5 mm under a tensile strength of 500 MPa. The Cu content in the busbar is 63.0%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. Subsequently, the obtained bus bar is coated with a zinc alloy layer having a thickness of 20 μm by a hot dipping method to form a shell layer base, thereby obtaining a wire blank. The zinc alloy has a Zn content of 49.5%, the remainder being inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. Thereafter, the wire blank is heat-treated and pressed to obtain a semi-finished electrode wire. The parameters of the heat treatment are a heat treatment temperature of 480 ° C., a heat treatment time of 8 hours, and nitrogen filling protection is performed in the heat treatment process. The parameters of the press processing are a processing speed of 1200 m / min, a processing voltage of 40 V, a current of 15 A, and a processing rate of 69.1%. Finally, the semi-finished electrode wire manufactured above is passivated and dried to form a protective layer having a thickness of 0.2 μm. Since the protective layer prevents oxidation of the electrode wire, the storage period of the electrode wire can be extended. The dry temperature is 80 ° C., and the final diameter of the final electrode wire is Φ0.3 mm.

  The manufactured electrode wire forms a core material by the above-described bus bar. The shell layer outside the core material includes a shell layer base and a protective layer, and electrode points and passages are formed in the shell layer base by performing heat treatment and press working. In this comparative example, the thickness of the shell layer is 20 μm, the hardness is HB30, the cross-sectional shrinkage is 80%, and the conductivity is 23% IACS.

The electrode points are embedded in the shell layer base, and the ratio of the electrode points to the shell layer base is 70%, and 80% of the electrode points are provided in an annular shape around the core material and evenly on the outside of the core material. . The electrode point is an electrode fine particle, the average particle size is 1200 nm, is composed of a large amount of an electronic compound of Cu ₃ Zn ₂ and Cu ₅ Zn ₈ , and is in the form of an ordered solid solution based on Cu ₃ Zn and Cu ₉ Zn. In the shell layer base. In addition, the shell layer base is provided with a passage in the vicinity of the surface of the electrode point, the passage is in the form of a micropore, and the average pore diameter is 100 nm.

<Comparative Example 7>
A core material is formed of a copper-zinc alloy which is a galvanized electrode wire and has a diameter of Φ0.6 to Φ1.5 mm. The component composition of the core material is the same as the core material in the electrode wire of the finished product in Example 7. After galvanizing the surface of the core material to obtain the second wire blank with a galvanized thickness of 10 to 30 um, the second wire blank is continuously pulled and processed by continuous annealing. A galvanized wire electrode having a diameter of 0.20 to 0.35 mm is manufactured.

<Comparative Example 8>
A copper zinc alloy wire blank is subjected to tensile processing at a tensile strength of 400 to 600 MPa to produce a bus bar having a diameter of Φ0.6 to Φ1.5 mm. The Cu content of the copper-zinc alloy is 58.5 to 68.5%, the remainder is Zn and inevitable impurity elements, and the content of inevitable impurity elements is 0.3% or less. A normal brass electrode wire having a diameter of 0.20 to 0.35 mm is manufactured by continuously pulling such a bus bar and performing continuous annealing.

  For the finally formed electrode wires produced in Comparative Examples 1-8, the overall mechanical properties were tested with a universal electronic extensometer, the conductivity was tested with the bridge method, When the high-quality carbon steel S45C having a length of 60 mm is used as a workpiece and the electric discharge machining speed and the consumption amount of the finally formed electrode wire are tested, the test result data is as shown in Table 1.

  As described above, there is a clear advantage in the processing speed and consumption of the high efficiency and low consumption electrode wire according to the present invention, the conductivity is higher than that of the same kind of product, and the tensile strength exceeds that of the same kind of product. It has become so much.

  The above examples are for interpreting and explaining the present invention and are not intended to limit the present invention. All modifications and changes made to the present invention within the spirit of the present invention and the protection scope of the claims are included in the protection scope of the present invention.

(Table 1) Performance test data of finished product electrode wires obtained in Examples and Comparative Examples

Chinese Patent Application No. 101829822

Claims (9)

A core material and a shell layer, wherein the material of the core material is Cu or a copper alloy, and the material of the shell layer is Zn or a zinc alloy.
The shell layer includes a shell layer base that covers the surface of the core material, an electrode point, and a protective layer that covers the surface of the shell layer base,
The electrode points are electrode fine particles embedded in the shell layer base,
The electrode fine particles are composed of a large amount of an electronic compound of a copper-zinc alloy,
In the shell layer base, a passage extending from the inside to the outside is distributed around the electrode point and / or in the center of the shell layer base. It is characterized by
High efficiency and low consumption electrode wire for electric discharge corrosion processing. Each component in the shell layer is Zn in the range of 42.5 to 52.5% by mass, the remaining amount is inevitable impurities accompanying Cu and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. It is characterized by
The electrode wire for electric discharge corrosion processing with high efficiency and low consumption according to claim 1. The shell layer has a thickness of 10 to 50 μm,
The electrode wire for electric discharge corrosion processing with high efficiency and low consumption according to claim 2. The electrode point has a particle size of 200 to 2000 nm, and the ratio of the electrode point to the shell layer base is 20 to 80%,
The electrode wire for electric discharge corrosion processing with high efficiency and low consumption according to claim 1. 80% of the electrode points are annularly distributed around the core material, and are uniformly distributed outside the core material,
The electrode wire for electric discharge corrosion processing with high efficiency and low consumption according to claim 4. The electronic compound of the copper zinc alloy is at least one of CuZn, Cu ₃ Zn ₂ , and Cu ₅ Zn ₈ ,
The electrode wire for electric discharge corrosion processing with high efficiency and low consumption according to claim 4. Each component in the core material is 58.5 to 68.5% of Cu in mass percent, the remaining amount is inevitable impurities accompanying Zn and raw materials, and the sum of the contents of inevitable impurities is 0.3% or less. It is characterized by
The electrode wire for high-efficiency and low-consumption electric discharge corrosion processing according to any one of claims 1 to 6. The protective layer has a thickness of 0.1 to 0.5 μm,
The electrode wire for high-efficiency and low-consumption electric discharge corrosion processing according to any one of claims 1 to 6. (1) A process for producing the core material, in which a copper or copper alloy is pulled at a tensile strength of 400 to 600 MPa to produce a bus bar having a wire diameter of Φ0.6 to Φ1.5 mm. Among them, the content of Cu is 58.5 to 68.5%, the remaining amount is Zn and unavoidable impurity elements, the content of unavoidable impurity elements is 0.3% or less,
(2) Manufacture of the shell layer base, wherein a first wire blank is obtained by coating the manufactured bus bar with a single layer of Zn or zinc alloy having a thickness of 10 to 50 μm to form a shell layer base. In the zinc alloy, the zinc content is 42.5 to 99%, the remaining amount is inevitable impurities associated with Cu and raw materials, and the sum of the inevitable impurity content is 0.3% or less. The shell layer base has a hardness of HB20-50, a cross-sectional shrinkage of 60% or more, and a conductivity of 22-25% IACS,
(3) By the heat treatment and press processing of the first wire blank, the desired electrode point and the passage are obtained in the shell layer base, and a semi-finished electrode wire is obtained. The process of forming the passage, the parameters of the heat treatment are the heat treatment temperature of 400 to 500 ° C., the heat treatment time of 2 to 10 hours, the nitrogen treatment is protected during the heat treatment process, and the parameters of the press working treatment are the processing A process in which the speed is 500 to 1500 m / min, the machining voltage is 10 to 50 V, the current is 5 to 20 A, and the machining rate is 82.6 to 97.2%;
(4) A process for producing a protective layer, in which a semi-finished product of the electrode wire is subjected to passivation treatment and dry treatment to form a protective layer having a thickness of 0.1 to 0.5 μm, and the dry temperature Is a process in which the diameter of the finished electrode wire finally obtained is Φ0.2 to Φ0.35 mm at 50 to 100 ° C.,
The method for producing an electrode wire for high-efficiency and low-consumption electric discharge corrosion processing according to claim 1, comprising: