JP2008100348A - Manufacturing method of cutting blade for manufacturing glass chopped strand and cutting blade for manufacturing glass chopped strand - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a cutting blade for manufacturing a glass chopped strand, which can suitably join an edge section and base section because stress remained on an alloy layer joining the edge section and base section is small and lessens breakages of the edge section because strength of the alloy layer itself is high. <P>SOLUTION: The manufacturing method of a cutting blade for manufacturing a glass chopped strand joins the edge section 1a and base section 1b via the alloy layer 1c by irradiating a coordinating section with a laser beam after coordinating the edge section 1a made of a cemented carbide and the base section 1b made of a carbon tool steel through a nickel foil or cobalt foil N. The cutting blade for manufacturing a glass chopped strand is manufactured by the manufacturing method of a cutting blade for manufacturing a glass chopped strand. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cutting blade for producing glass chopped strands suitable for cutting glass fibers into a certain length.

  Glass fiber is produced by drawing molten glass from a number of nozzles formed at the bottom of the bushing, spinning it as a continuous thin glass filament, cooling it with water spray, and coating the surface with a sizing agent. The glass strands are formed by concentrating several hundred to several thousand pieces, and the glass strands are wound with a winder to form a roving yarn called a cake. The wound glass strand is used as a yarn through a twisting process as a yarn or as a glass roving through a spinning process, and is used as a glass chopped strand of a certain length through a chopping process. It is used for GRC (abbreviation for glass fiber reinforced cement).

  As the fiber cutting device used for cutting the glass strand in the chopping process, a device as shown in FIG. 3 is generally used. This apparatus includes a cutter roller 2 in which a plurality of cutting blades 1 are radially attached at equal intervals, and a rubber roller 3 having a rubber attached to the outer peripheral surface. A glass strand G is interposed between the cutter roller 2 and the rubber roller 3. Is cut into a predetermined length (for example, 1.5 to 12 mm).

  Conventionally, the cutting blade 1 attached to this type of cutter roller 2 has been subjected to quenching and tempering because of its excellent impact resistance. In general, a carbon tool steel having a Vickers hardness of about 800 is polished and subjected to a cutting process. However, the cutting blade 1 made of such carbon tool steel is worn out as the blade portion wears over time. In particular, glass fibers are harder than organic fibers and the like, so that the blade portion is heavily worn, and it is necessary to replace the cutting blades every several hours, which causes a reduction in production efficiency.

  In addition, cemented carbide has been known as a metal with excellent wear resistance from the past, and cemented carbide has the advantage that it can be reused if it is worn, but in terms of impact resistance. There is a disadvantage of being inferior. For this reason, when an excessive impact load is applied to the cutting blade 1 when the cutter roller 2 is rotated at a high speed with a cutting device in which the cutting blade 1 for manufacturing glass chopped strands made of cemented carbide is attached to the cutter roller 2. Since there is a risk of breakage and scattering, the cutter roller 2 must be rotated at a low speed, which has been an obstacle to improving production efficiency.

  In order to deal with the above problem, the applicant of the present application in Patent Document 1, the blade portion is made of cemented carbide, the base portion is made of carbon tool steel subjected to quenching and tempering, and the blade tip and the base portion are made of nickel. A fiber cutting blade joined through an alloy layer has been proposed.

The above-mentioned fiber cutting blade is excellent in wear resistance because the blade portion is made of cemented carbide, and excellent in impact resistance because the base portion is made of carbon tool steel subjected to quenching and tempering. Since the base portion absorbs vibration when the fiber is cut, breakage of the blade portion can be suppressed. Further, in this fiber cutting blade, the blade portion and the base portion are joined via a nickel alloy layer, and this nickel alloy layer is obtained by melting nickel into carbon tool steel and cemented carbide. Because it has a thermal expansion coefficient that is close to that of cemented carbide, which is the material of the joint, the residual stress at the joint between the blade and the base is reduced, and no deformation occurs at the joint. It has the advantage of being able to achieve strength.
Japanese Patent Laid-Open No. 11-123893

  Patent Document 1 discloses a method for producing a fiber cutting blade by coating a carbon tool steel by thermal spraying nickel and then performing laser welding in a state where the coated portion and one end of the cemented carbide are aligned. However, the cutting blade manufactured by such a method sometimes has excessive thermal stress remaining in the joint portion, or the strength of the alloy layer itself may be insufficient.

  The present invention has been made in view of the above problems, and the purpose thereof is to satisfactorily join the blade portion and the base portion because the residual stress in the alloy layer joining the blade portion and the base portion is small. Another object of the present invention is to provide a cutting blade for producing glass chopped strands, which has a high strength of the alloy layer itself and therefore has little blade breakage.

  The method for producing a cutting blade for producing glass chopped strands according to the present invention comprises aligning a blade portion made of cemented carbide and a base portion made of carbon tool steel via a nickel foil or cobalt foil, and then aligning the alignment portion with a laser. By irradiating, the blade part and the base part are bonded via an alloy layer.

  Moreover, the manufacturing method of the cutting blade for glass chopped strand manufacture of this invention is based on the YAG laser with which laser irradiation is irradiated toward nickel foil.

  Moreover, the manufacturing method of the cutting blade for glass chopped strand manufacture of this invention is characterized by the thickness of nickel foil being 0.2-0.5 mm.

  The cutting blade for manufacturing a glass chopped strand of the present invention is manufactured by the method for manufacturing a cutting blade for glass fiber of the present invention.

  In the present invention, the length in the width direction of the alloy layer is preferably 0.7 to 3.5 times the length in the cross-sectional direction of the alloy layer. The reason is as follows. As shown in FIG. 1, the cutting blade for fibers of the present invention has a blade portion 1a made of cemented carbide and a base portion 1b made of carbon tool steel joined through an alloy layer 1c. If the length t1 in the width direction is less than 0.7 times the length t2 in the cross-sectional direction, the residual stress at the joint portion between the blade portion 1a and the base portion 1b becomes too large, and the joint portion is deformed. And the strength decreases. On the other hand, if the length t1 in the width direction of the alloy layer 1c exceeds 3.5 times the length t2 in the cross-sectional direction, the strength of the alloy layer is reduced, and the alloy layer itself is rotated when the cutter roller is rotated at high speed. Breakage. A preferable range of t1 / t2 is 0.75 to 2.5, and a more preferable range is 0.8 to 2.

  In order to make the length in the width direction of the alloy layer 0.7 to 3.5 times the length in the cross-sectional direction of the alloy layer, the blade portion made of cemented carbide and carbon tool steel are used. After aligning the base portion via a nickel foil or cobalt foil, the blade portion and the base portion may be joined by a nickel alloy layer or a cobalt alloy layer by irradiating the alignment portion with a laser. That is, in the conventional method of spraying nickel onto the base portion, the adhesion state of nickel becomes unstable and it is difficult to control the shape of the nickel alloy layer. However, as in the present invention, at one end of the base portion. After aligning the metal foil made of nickel or cobalt and aligning the rear end of the blade part to the metal foil, when the alignment part is irradiated with laser and heated, nickel or cobalt is the main component of carbon tool steel Although the alloy layer is formed by dissolving in iron and dissolving in the cemented carbide, the dimensional ratio of the alloy layer can be controlled by selecting the thickness of the metal foil.

As the cemented carbide forming the blade portion of the present invention, an extremely hard alloy obtained by mixing and sintering a powder of a metal element carbide and a metal powder can be used, and this alloy has excellent wear resistance. Even if worn, it can be reused if it is polished. Specifically, WC-Co, WC-TaC-Co, WC-TiC-Co, and WC-TiC-TaC-Co alloys can be used, and the thermal expansion coefficient of these alloys is 25 to 200. It is 48-62 * 10 < ^-7 > / degreeC in the temperature range of degreeC.

Moreover, the carbon tool steel forming the base portion of the present invention is obtained by quenching and tempering iron containing carbon, and is excellent in impact resistance. Specifically, SK-5, SK-2 and the like can be used, and their thermal expansion coefficient is 100 to 120 × 10 ⁻⁷ / ° C. in a temperature range of 25 to 200 ° C.

  In this invention, it is preferable that the alloy layer which joins a blade part and a base | substrate part is a nickel alloy layer or a cobalt alloy layer. That is, when nickel or cobalt is disposed between the blade portion and the base portion and welded, nickel or cobalt is melted into the carbon tool steel and the cemented carbide and integrated. In particular, the nickel alloy layer is suitable because it has a thermal expansion coefficient that is close to that of cemented carbide, so that residual stress hardly occurs, material costs are low, and workability is excellent.

  The thickness of the glass chopped strand manufacturing cutting blade according to the present invention is preferably 0.3 to 4.5 mm. If the thickness of the cutting point is less than 0.3 mm, the strength is lowered, and if the thickness of the cutting blade exceeds 4.5 mm, it becomes difficult to shorten the cut length of the fiber. Practically, a more preferable thickness of the cutting blade is 0.3 to 1.5 mm.

  The cutting blade for producing glass chopped strand according to the present invention is preferably configured so that the Vickers hardness of the blade portion is 2.0 to 3.0 times the Vickers hardness of the base portion. The reason is that if the Vickers hardness of the blade part is less than 2.0 times the Vickers hardness of the base part, the entire cutting blade is liable to be excessively deformed (sticky) when the fiber is cut, especially when the rubber roller is worn out. In this case, the cutting edge does not hit the fiber accurately, and erroneous cutting (miscut) is likely to occur. On the contrary, if it exceeds 3.0 times, the difference in thermal expansion coefficient between the two becomes large and stable bonding is achieved. This is because it is difficult to do.

  Further, in the cutting blade for producing glass chopped strand according to the present invention, the length from the joining end to the other end of the base portion (the width of the base portion) is the length from the joining end of the blade portion to the blade edge (the width of the blade portion). It is desirable to make it 2 to 5 times as large as). The reason is that if the width of the base portion is less than twice the width of the blade portion, it becomes difficult for the base portion to sufficiently absorb vibration when the cutter roller is rotated at a high speed, and conversely, it exceeds 5 times. This is because the width of the blade portion is relatively shortened due to the limitation due to the mounting dimensions of the fiber cutting blade, and the polishing allowance of the blade portion is reduced.

  Next, the manufacturing method of the cutting blade for glass chopped strand manufacture of this invention is demonstrated.

First, as a blade part, 85-95 mass% tungsten carbide (WC) powder with an average particle diameter of 0.5-1.0 μm and 5-15 mass% cobalt (Co) powder are blended and sintered. Cemented carbide formed into a predetermined dimension (for example, the length from the joining end of the blade part to the blade edge is 3 to 7 mm), and 0.8 to 1.3% by mass of carbon as the base part Carbon tool steel formed into a predetermined dimensional shape (for example, the length from the joining end to the other end of the base portion is set to 12 to 20 mm) by quenching and tempering iron (Fe) containing (C). prepare. Next, a nickel foil (thickness 0.2 to 0.5 mm) is aligned with the tip of the base portion made of carbon tool steel, and the rear end of the blade portion made of cemented carbide is aligned with the tip of the base portion aligned with the nickel foil. After the alignment, the nickel foil is irradiated with a laser and heated. Thereby, nickel, carbon tool steel, and a cemented carbide are heated locally, and a nickel alloy layer is formed, and a blade part and a base part are joined by this nickel alloy layer. This nickel alloy layer (with a thermal expansion coefficient of 40 to 47 × 10 ⁻⁷ / ° C. in a temperature range of 30 to 300 ° C.) is a solid solution of nickel in iron, which is a component of carbon tool steel, and also into a cemented carbide. Since it has a thermal expansion coefficient approximate to that of a cemented carbide (thermal expansion coefficient: 48 to 62 × 10 ⁻⁷ / ° C. in a temperature range of 25 to 200 ° C.) which is a material of the blade portion, the blade portion The thermal stress remaining in the joint portion between the base portion and the base portion is small, and the blade portion and the base portion are firmly joined without causing deformation in the joint portion. After joining the blade portion and the base portion in this manner, a cutting blade for fibers is obtained by performing a cutting process on the tip of the blade portion. Moreover, it is also possible to use a cobalt foil instead of the nickel foil, and to join the blade portion and the base portion by irradiating with a laser beam.

  The fiber cutting device equipped with the cutting blade for producing the glass chopped strand of the present invention has a plurality of cutting blades radially attached to the surface of the cutter roller, and since the wear of the blade portion is small, the glass fiber This device is suitable for cutting such hard fibers, and even when the cutter roller is rotated at high speed, the base part sufficiently absorbs vibration, so that the cutting edge is less likely to break and the productivity of glass chopped strands is reduced. Can be greatly improved. The cutting blades may be attached to the cutter roller so that the cutting blades are equally spaced.

  Moreover, in the fiber cutting device equipped with the cutting blade for producing the glass chopped strand according to the present invention, when the cutting blades are arranged at a short distance (for example, 3 mm intervals), the cutting blades come into contact with each other and gradually wear and break. However, it is preferable to attach a cushioning material such as rubber (for example, a thickness of 0.2 to 0.5 mm) or a metal spacer to both surfaces of the cutting blade because the cutting blade is difficult to break.

  As described above, the cutting blade for producing a glass chopped strand according to the present invention has a small residual stress in the alloy layer that joins the blade portion and the base portion, and therefore can satisfactorily join the blade portion and the base portion, and the alloy layer itself. High strength and low wear of the blade, it can be used for a long time, and it has excellent impact resistance, so even if the cutter roller is rotated at high speed, there is little breakage and production efficiency is greatly improved. Can be achieved.

  Further, the fiber cutting device equipped with the cutting blade for producing the glass chopped strand of the present invention is suitable for cutting hard fibers such as glass fiber because the blade portion of the cutting blade is less worn, and the productivity of the glass chopped strand is high. Can be greatly improved.

  Hereinafter, the Example of the cutting blade for glass chopped strand manufacture of this invention is described in detail based on drawing.

  1A and 1B are explanatory views showing a cutting blade for producing a glass chopped strand according to the present invention, in which FIG. 1A is a front view and FIG. 1B is a sectional view taken along line YY of FIG.

The cutting blade 1 for producing glass chopped strand is composed of 90% by mass of tungsten carbide (WC) having an average particle diameter of 0.5 μm and 10% by mass of cobalt (Co), and has a Vickers hardness of Hv. 1700 blade portion 1a (thickness 1.2 mm, width 5 mm) formed of cemented carbide 1700 (thermal expansion coefficient 57 × 10 ⁻⁷ / ° C. in a temperature range of 25 to 200 ° C.), and 98% by mass of iron (Fe) and 0.8% by mass of carbon (C), quenched and tempered, having a Vickers hardness of Hv. A base portion 1b (wall thickness: 1.2 mm, width: 13 mm) formed of a carbon tool steel of 800 (SK-5: thermal expansion coefficient 112.5 × 10 ⁻⁷ / ° C. in a temperature range of 20 to 200 ° C.) It has. The blade portion 1a and the base portion 1b are joined together via a nickel alloy layer 1c (coefficient of thermal expansion 40 to 47 × 10 ⁻⁷ / ° C. in a temperature range of 30 to 300 ° C.), and the length of the alloy layer in the width direction. t1 is 1.0 mm, and the length t2 of the alloy layer in the cross-sectional direction is 1.2 mm. In addition, t1 measures the length of the surface part of an alloy layer, and t2 measures the space | interval of the surface parts of an alloy layer.

  The above-described cutting blade 1 for producing glass chopped strands was produced as follows.

  First, as shown in FIG. 2 (A), a tungsten carbide (WC) fine particle containing Co as a binder is fired and then subjected to HIP (Hot Isostatics Press) treatment to form a blade member made of a plate-like cemented carbide. 1a 'was produced. Further, a carbon tool steel subjected to quenching and tempering was produced and processed according to the end face shape of the blade member 1a ′ to produce the base part 1b.

  Next, as shown in FIG. 2B, a nickel foil N having a thickness of about 0.3 mm is aligned in the vicinity of the tip of the base portion 1b, and the blade member is positioned at the tip of the base portion 1b aligned with the nickel foil N. A YAG laser was irradiated toward the nickel foil N in a state where the rear ends of 1a ′ were aligned. By this YAG laser irradiation, the nickel foil N and the base portion 1b are heated, and as shown in FIG. 2 (C), nickel is mainly dissolved in iron which is a component of carbon tool steel, and at the same time, the cemented carbide is formed. As a result, the nickel alloy layer 1c 'is formed.

  After joining the blade member 1a ′ and the base portion 1b in this manner, as shown in FIG. 2D, the blade portion 1a and the base portion 1b are made of a nickel alloy layer by applying a cutting process to the tip of the blade member 1a ′. The cutting blade 1 for fibers joined through 1c was formed.

  A plurality of cutting blades 1 obtained in this way were attached radially around the cutter roller 2 at equal intervals as shown in FIG. Using this fiber cutting device, the cutter roller 2 was rotated at a peripheral speed of 500 m / min, and the glass strand G was cut to a length of 3 mm. We were able to use without problem.

  On the other hand, as comparative examples, cutting blades were formed under the same conditions as in the examples except that the length t1 in the width direction of the nickel alloy layer was 0.8 mm. When the glass strand G was cut under the same conditions as described above using the cutter roller 2 to which a plurality of cutting blades were attached, when about 30 hours had passed, a crack was found near the boundary between the base portion 1b and the nickel alloy layer 1c. It was confirmed that this occurred.

  As other comparative examples, cutting blades were formed under the same conditions as in the examples except that the length t1 in the width direction of the nickel alloy layer was 4.3 mm. When the glass strand G was cut under the same conditions as described above using the cutter roller 2 with a plurality of cutting blades attached, a crack occurred in the central portion of the nickel alloy layer 1c after about 15 hours had passed. Was confirmed.

  The Vickers hardness in the present invention is measured according to JIS Z2251.

It is explanatory drawing which shows the cutting blade for glass chopped strand manufacture of this invention, Comprising: (A) is a front view, (B) is the YY sectional view taken on the line of (A). It is explanatory drawing which shows the process of producing the cutting blade for glass chopped strand manufacture of this invention. It is a schematic explanatory drawing which shows a glass fiber cutting device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cutting blade for glass chopped strand production 1a Blade part 1b Base part 1c Nickel alloy layer 2 Cutter roller 3 Rubber roller G Strand N Nickel foil R Laser irradiation direction t1 Length of alloy layer in width direction t2 Length of alloy layer in cross-sectional direction

Claims (4)

  After aligning the blade portion made of cemented carbide and the base portion made of carbon tool steel via nickel foil or cobalt foil, the blade portion and the base portion are bonded to each other by irradiating the alignment portion with a laser. The manufacturing method of the cutting blade for glass chopped strand manufacture characterized by joining via.   The method for producing a cutting blade for producing a glass chopped strand according to claim 1, wherein the laser irradiation is performed by a YAG laser irradiated toward the nickel foil.   The thickness of a nickel foil is 0.2-0.5 mm, The manufacturing method of the cutting blade for glass chopped strand manufacture described in Claim 1 or Claim 2 characterized by the above-mentioned.   A cutting blade for producing glass chopped strands, which is produced by the method for producing a cutting blade for glass fibers according to claim 1.

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