JP2015107530A - Wire tool and wire tool manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wire tool and its manufacturing method having excellent cutting sharpness and a long tool life.SOLUTION: In a wire tool 100, an abrasive grain layer 50 is provided to be formed by fixing abrasive grains 20 to an outer periphery 1a of a core wire 1 with electrodeposition metal 30, and recessed chip pockets 40 and 40x having openings 40a are provided on the surface 30a of the electrodeposition metal 30. The opening 40a of the chip pocket 40 has a circular shape, and the partial chip pockets 40x of the plurality of the chip pockets 40 existing on the surface 30a of the electrodeposition metal 30 are adjacent to the abrasive grains 20. An inner diameter of the opening 40a of the chip pocket 40 is 5 μm or more and is equal to or less than an average particle diameter of the abrasive grains 20. The number of the chip pockets 40 existing in the abrasive grain layer 50 is 50-90% of the number of the abrasive grains 20.

Description

  The present invention relates to a wire tool used when slicing ingots such as silicon for solar cells, silicon for semiconductors, magnetic materials, sapphire, and SiC, and a method for manufacturing the wire tool.

  For wire tools used for slicing hard and brittle materials such as silicon for solar cells and silicon for semiconductors and sapphire ingots, resin wire tools with abrasive grains fixed by resin bonds and abrasive grains by electrodeposition It is roughly classified into a fixed electrodeposition wire tool (see, for example, Patent Documents 1 and 2).

  The electrodeposition wire tools described in Patent Documents 1 and 2 are excellent in terms of high abrasive grain holding power and high processing efficiency, but are low in flexibility and weak against twisting. It is inferior. Therefore, in order to increase the processing efficiency and torsional strength of the wire tool, and to prevent disconnection during the cutting process, the porous nickel plating layer applied to the outer periphery of the metal core wire and the surface of the nickel plating layer are fixed with a resin bond A wire tool provided with the superabrasive grains made has been proposed (for example, see Patent Document 3).

  In recent years, ingots that are cut using a wire tool have become larger, and it has become difficult to bring coolant into the work (ingot) along with the wire tool that is being cut. Therefore, as means for improving the function of bringing the coolant into the workpiece, abrasive grains are arranged in a spiral shape on the outer periphery of the core wire to form a chip pocket in a groove shape (for example, see Non-Patent Document 1), or a plurality of elements It has also been proposed to form a core wire by twisting the wires so that the gap between the strands becomes a chip pocket (see, for example, Patent Document 4).

  On the other hand, in order to obtain good machinability in grinding difficult-to-cut materials and to suppress the deformation of the shape of the abrasive grain layer after cutting, Patent Document 5 discloses abrasive grains in which superabrasive grains are dispersed in a resin binder phase. In the resin-bonded whetstone having a layer, the resin-bonded phase is obtained by dispersing hollow particles having a metal coating and metal powder as fillers in a matrix having a thermosetting resin as a main composition. (For example, refer to Patent Document 5).

  In addition, in the field of creep feed grinding, abrasive grains in which superabrasive grains are dispersed in a bond phase containing a resin as a binder in order to dissipate grinding heat reliably and effectively, improve the grinding ratio, and increase grinding accuracy. In a resin bond grindstone having a layer, a bond phase containing carbon, Ag particles and Cu particles, and a binder is described (for example, see Patent Document 6).

  Furthermore, in the field of electrodeposition grinding stones, in order to generate a self-generated blade action on the electrodeposition grinding stone and to grind difficult-to-cut materials satisfactorily, abrasive grains and hollow particles are mixed and fixed by a plating layer. An electrodeposited grindstone having a grindstone portion has been proposed (see, for example, Patent Document 7).

JP-A-53-14489 Japanese Patent No. 4157724 JP 2011-218492 A Japanese Patent Laid-Open No. 11-277398 Japanese Patent No. 3424540 JP 2011-104750 A JP 2005-329488 A

Journal of Japan Society for Precision Engineering 62 (2), p242-p246

  As described above, ingots that are cut using wire tools have become larger in recent years, and it has become difficult to bring coolant into the work (ingot) along with the wire tool being cut. However, the wire tool described in Patent Documents 1 and 2 cannot sufficiently cope with the wire tool.

  On the other hand, the wire tool described in Patent Document 3 includes a porous nickel plating layer, but this porous portion penetrates a resin bond fixed to the surface of the nickel plating layer to produce an anchor effect. In order to increase the adhesion between the metal core wire and the resin bond, it does not have a function of bringing the coolant into the workpiece during the cutting operation.

  In addition, the wire tool described in Non-Patent Document 1 or the wire tool described in Patent Document 4 has a core wire that is easily broken by twisting that occurs when an ingot is processed, and the tensile strength at break is weak in a core wire of the same thickness. turn into.

  On the other hand, the resin bond grindstones described in Patent Documents 5 and 6 are substantially different from the wire tool according to the present invention in terms of bond type, tool shape, and application field, and thus cannot be employed. In addition, if the hollow particles have conductivity, plating is placed on the surfaces of the hollow particles, which hinders the formation of a chip pocket. Further, if the abrasive grain surface is coated with a conductive metal and the average grain diameter of the abrasive grains is not larger than the average grain diameter of the hollow grains, the conductive wire cannot be connected to the pulley in the plating step, and the abrasive grains and hollow There is also a problem that the particles cannot be sufficiently fixed.

  Furthermore, the electrodeposition grindstone described in Patent Document 7 promotes the self-generated blade action due to the abrasive grains falling during the grinding operation by mixing abrasive grains and hollow particles, but brings the coolant into the workpiece. It has no function and cannot be applied to the field of wire tools.

  The problem to be solved by the present invention is to provide a wire tool having a good sharpness and a long tool life and a method for manufacturing the same.

  The wire tool of the present invention is a wire tool having an abrasive grain layer formed by adhering abrasive grains to the outer periphery of a core wire with an electrodeposited metal, and a concave chip pocket having an opening on the surface of the electrodeposited metal It is provided with.

  With this configuration, the chip pocket having the opening on the surface of the electrodeposited metal increases the function of bringing the coolant into the workpiece during cutting of the workpiece, so that the heat generation of the workpiece is suppressed, and the grinding debris can be quickly removed. Since the effective discharge is promoted, the sharpness is improved. In addition, the excessive heat and friction of the abrasive grains can be prevented by the heat generation suppressing action described above, so that the tool life is extended.

  Here, the opening of the chip pocket is preferably circular.

  Moreover, it is desirable that at least a part of the chip pockets on the surface of the electrodeposited metal is adjacent to the abrasive grains.

  Furthermore, it is desirable that the inner diameter of the opening of the chip pocket is 5 μm or more and not more than the average particle diameter of the abrasive grains.

  Meanwhile, it is desirable that the number of the chip pockets is 50% to 90% of the number of the abrasive grains.

  Next, the wire tool manufacturing method of the present invention is a method of manufacturing a wire tool having an abrasive layer formed by fixing abrasive grains to the outer periphery of a core wire with an electrodeposited metal, and the abrasive grains on the outer peripheral surface of the core wire. And temporarily fixing the spherical hollow particles, fixing the abrasive grains and the hollow particles with an electrodeposited metal, and destroying or dropping the hollow particles exposed from the surface of the electrodeposited metal; , Provided.

  With such a configuration, it is possible to efficiently manufacture a wire tool including a concave chip pocket having an opening on the surface of the electrodeposited metal.

  Here, it is desirable that the surface of the abrasive grains be coated with a conductive material and the surface of the hollow particles be non-conductive.

  The hollow particles are preferably made of silicon oxide (silica) or aluminum oxide (alumina), and the average particle diameter of the hollow particles is preferably 5 μm or more and less than the average particle diameter of the abrasive grains.

  According to the present invention, it is possible to provide a wire tool having a good sharpness and a long tool life and a manufacturing method thereof.

It is a partially expanded perspective view of the outer periphery of the wire tool which is embodiment of this invention. It is a partially expanded perspective view of the other part of the outer periphery of the wire tool shown in FIG. It is a figure which shows the manufacturing method of the wire tool shown in FIG. It is a figure which shows the manufacturing method of the conventional wire tool. It is sectional drawing which shows a part of manufacturing process of the wire tool shown in FIG. It is a partial abbreviation figure which shows the cutting process operation | work with the wire tool shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1, 2, and 5 (c), the wire tool 100 of the present embodiment has an abrasive grain layer 50 formed by fixing abrasive grains 20 to an outer periphery 1 a of a core wire 1 with an electrodeposited metal 30. And has recessed chip pockets 40, 40x having openings 40a on the surface 30a of the electrodeposited metal 30. As shown in FIG. 1, the opening 40 a of the chip pocket 40 is circular, and as shown in FIGS. 2 and 5 (c), among the plurality of chip pockets 40 existing on the surface 30 a of the electrodeposited metal 30. A part of the chip pockets 40 x are adjacent to the abrasive grains 20.

  The inner diameter of the opening 40 a of the chip pocket 40 is not less than 5 μm and not more than the average particle diameter of the abrasive grains 20. The number of chip pockets 40 present in the abrasive grain layer 50 is 50% to 90% of the number of abrasive grains 20.

  With such a configuration, as shown in FIG. 6 described later, when the workpiece 65 (silicon ingot) is cut using the wire tool 100, the surface 30a of the electrodeposited metal 30 has an opening 40a. Since the function of bringing the coolant 66 into the workpiece 65 is enhanced by the chip pocket 40, the heat generation of the workpiece 65 is suppressed, and the quick discharge of the grinding waste is promoted, so that the sharpness is improved. In addition, the excessive heat and friction of the abrasive grains 20 can be prevented by the heat generation suppressing action described above, so that the tool life is extended.

  Here, based on FIG. 3, the manufacturing method of the wire tool 100 of this embodiment is demonstrated. As shown in FIG. 3, a piano wire (wire diameter φ180 μm), which is the core wire 1, is continuously supplied at a wire speed of 30 m / min, and the outer circumference of the core wire 1 sequentially in the degreasing tank 2 and the acid cleaning tank 3. Is cleaned to remove dirt, oil, and the like on the outer periphery of the core wire 1. The core wire 1 exiting the acid cleaning tank 3 is sent to a solution application tank 4 where a solution (not shown) is applied to the outer periphery of the core wire 1 and is extra in a die 5 disposed after the solution application tank 4. The solution is removed. In addition, although the said solution used what melt | dissolved 1 mass% of pentaerythritol triacrylate resins in alcohol, it does not limit to this.

  Thereafter, in the diamond spraying tank 6, the diamond abrasive grains 20 (average particle diameter 35 μm) and the spherical hollow particles 25 are temporarily fixed by a spraying method, resulting in a state as shown in FIG. In the diamond spray tank 6, since the spherical hollow particles 25 (hollow silica filler: average particle diameter 20 μm) are sprayed in the diamond abrasive grains 20, the diamond abrasive grains 20 and the hollow particles 25 are sprayed simultaneously. Can be temporarily fixed. Here, the surface of the diamond abrasive grain 20 is coated with a conductive material, but the surface of the hollow particle 25 is non-conductive. In addition, although the hollow particle 25 of this embodiment is formed with silicon oxide, it can also be formed with aluminum oxide.

Then, after nickel plating is performed at a current density of 50.7 A / dm ² in the plating tank 7 and then passed through the degreasing tank 8 and the cleaning tank 9, as shown in FIG. The wire tool 10 in a state where the grains 20 and the hollow particles 25 are fixed by the electrodeposited metal 30 is formed.

  When the wire tool 10 formed through the manufacturing process shown in FIG. 3 is subjected to a sharpening process such as truing or dressing, the hollow particles 25 shown in FIG. 5B are broken or dropped off, As shown in FIG. 5C, the wire tool 100 is formed in which the traces of the hollow particles 25 on the surface 30 a of the electrodeposited metal 30 become the chip pockets 40. In the wire tool 100, the number of abrasive grains 20 per unit area is 25, the number of chip pockets 40 is 15, and the number of chip pockets 40 is 60% of the number of abrasive grains 20. However, it is not limited to these.

  The unit area is an area within the range of 160 μm in the circumferential direction × 1000 μm in the length direction on the outer peripheral surface of the wire tool 10 (the surface 30a of the electrodeposited metal 30), and the abrasive grains 20 per unit area ( The number of chip pockets 40) is the average of the values obtained by counting the number of abrasive grains 20 (chip pockets 40) for the 20 unit area portions.

Here, the manufacturing method of the conventional wire tool 13 is demonstrated based on FIG. As shown in FIG. 4, a piano wire (wire diameter φ180 μm), which is the core wire 1, is continuously supplied at a wire speed of 30 m / min. After removing dirt and oil on the outer periphery of the core wire 1 and performing base plating in the base plating tank 11, diamond abrasive grains (particle size 30/40) are electrophoresed in the electrophoresis tank 12. Is temporarily fixed. Thereafter, after the diamond abrasive grains are fixed by performing nickel plating (current density 50.7 A / dm ² ) in the plating tank 7, the wire tool 13 is completed when passing through the degreasing tank 8 and the cleaning tank 9.

  Next, a wire tool 100 (see FIG. 5C) formed by applying a sharpening process such as truing (or dressing) to the wire tool 10 manufactured through the steps shown in FIG. 3, and shown in FIG. About the conventional wire tool 13 manufactured through the process, the workpiece | work 65 (silicon ingot) was cut using the wire saw 60 shown in FIG. 6, and the cooling property was evaluated.

  The wire saw 60 is an automatic diamond wire saw (CS-400 type) manufactured by DWT (Diamond Wire Technology). The wire tools 100 and 13 are set on the wire saw 60 and the workpiece 65 (single crystal silicon ingot) is cut. Went. As shown in FIG. 6, in the wire saw 60, the intervals between the plurality of pulleys 64a and 64b are 300 mm, and during the cutting process, the coolant 66 (Noritake Cool) directly from the supply guide 62 to the pulleys 64a and 64b, respectively. ) At a rate of 0.4 L / min. The wire tools 100 and 13 have a linear velocity of 350 m / min and a wire tension of 13N. The workpiece 65 is a single crystal silicon ingot having a height of 70 mm.

  As shown in FIG. 6, while cutting the workpiece 65, the temperature of the cutting area 63 inside the workpiece 65 (the area where the wire tools 100 and 13 are in contact with the workpiece 65) is set to 10 minutes after the start of the cutting process. When measured every 20 minutes, 30 minutes, 40 minutes and 50 minutes, the results shown in Table 1 were obtained. In addition, the temperature measurement of the cutting | disconnection area | region 63 was performed using the infrared radiation thermometer with a laser marker (AD-5611A) of A & D company. By measuring the temperature every 10 minutes, the cooling performance by bringing in the coolant accompanying the wire tools 100 and 13 during the cutting operation was evaluated.

(Table 1) Evaluation results of cooling performance of wire tools

  Referring to Table 1, when the workpiece 65 is cut using the wire tool 100, the temperature of the cutting region 63 is 22.3 ° C. when 10 minutes have elapsed, and up to 28.0 ° C. after 40 minutes have elapsed. Although it has risen, it has been lowered to 26.1 ° C. after 50 minutes, so that it can be seen that the temperature is generally kept within the range of 22.3 to 28.0 ° C.

  On the other hand, when the workpiece 65 is cut using the wire tool 13, the temperature of the cutting region 63 is 21.7 ° C. when 10 minutes have elapsed, but rapidly rises to 31.4 ° C. after 20 minutes, After the elapse of minutes, the temperature rises to a maximum of 35.4 ° C., and is 32.3 ° C. even after the elapse of 50 minutes.

  From the above, on the outer periphery of the wire tool 100 shown in FIG. 5 (c), as shown in FIGS. 1 and 2, a chip having an opening 40a in the vicinity of the abrasive grains 20 or on the surface 30a of the electrodeposited metal 30. Since the pocket 40 is present, the coolant 66 is continuously supplied into the work 65 along with the wire tool 100 during the cutting operation, so that the heat generation of the work 65 is suppressed, the cutting waste is quickly discharged, and the sharpness is excellent. Demonstrate. Further, since the heat generation of the workpiece 65 is suppressed, excessive frictional wear of the abrasive grains 20 is suppressed, so that the tool life is improved.

  The embodiments of the wire tools 10 and 100 and the manufacturing method thereof described with reference to FIGS. 1 to 6 exemplify the present invention, and the wire tool and the wire tool manufacturing method of the present invention are described above. It is not limited to.

  The wire tool of the present invention can be widely used in various industrial fields for slicing ingots such as silicon for solar cells, silicon for semiconductors, magnetic materials, sapphire, and SiC.

DESCRIPTION OF SYMBOLS 1 Core wire 1a Outer periphery 2,8 Degreasing tank 3 Acid cleaning tank 4 Solution application tank 5 Dies 6 Diamond spraying tank 7 Plating tank 9 Cleaning tank 10, 13, 100 Wire tool 11 Base plating tank 12 Electrophoresis tank 20 Abrasive grain 25 Hollow particle 30 Electrodeposited metal 30a Surface 40, 40x Chip pocket 40a Opening 50 Abrasive layer 60 Wire saw 62a, 62b Supply guide 63 Cutting region 64a, 64b Pulley 65 Work 66 Coolant

Claims (8)

  A wire tool having an abrasive grain layer formed by adhering abrasive grains to an outer periphery of a core wire with an electrodeposited metal, comprising a concave chip pocket having an opening on the surface of the electrodeposited metal Wire tool to play.   The wire tool according to claim 1, wherein the opening of the chip pocket is circular.   The wire tool according to claim 1 or 2, wherein at least a part of the chip pockets on the surface of the electrodeposited metal is adjacent to the abrasive grains.   The wire tool according to any one of claims 1 to 3, wherein an inner diameter of the opening of the chip pocket is not less than 5 µm and not more than an average particle diameter of the abrasive grains.   The wire tool according to any one of claims 1 to 4, wherein the number of the chip pockets is 50% to 90% of the number of the abrasive grains.   A method of manufacturing a wire tool having an abrasive layer formed by fixing abrasive grains to the outer periphery of a core wire with an electrodeposited metal, the step of temporarily fixing abrasive grains and spherical hollow particles to the outer periphery of the core wire, and A method of manufacturing a wire tool, comprising: a step of fixing abrasive grains and the hollow particles with an electrodeposited metal; and a step of breaking or dropping the hollow particles exposed from the surface of the electrodeposited metal. .   The wire tool manufacturing method according to claim 6, wherein a surface of the abrasive grains is coated with a conductive substance, and a surface of the hollow particles is non-conductive.   The wire tool manufacturing method according to claim 6 or 7, wherein the hollow particles are formed of silicon oxide or aluminum oxide, and the average particle size of the hollow particles is 5 µm or more and less than the average particle size of the abrasive grains.