WO2022004523A1

WO2022004523A1 - Method for manufacturing coated tool

Info

Publication number: WO2022004523A1
Application number: PCT/JP2021/023785
Authority: WO
Inventors: 健二熊井
Original assignee: 京セラ株式会社
Priority date: 2020-06-30
Filing date: 2021-06-23
Publication date: 2022-01-06
Also published as: CN115916454A

Abstract

A method for manufacturing a coated tool according to the present disclosure, which is not a limiting example thereof, is a method for manufacturing a coated tool having a base and a coating layer located on the base. The method for manufacturing a coated tool includes a first step for preparing an untreated coated tool having an untreated coating layer on the base, and a second step for causing spherical ceramic particles having a hardness (HV) of 1,000 or more to collide with the untreated coating layer.

Description

Manufacturing method of covering tool

Cross-reference of related applications

This application claims the priority of Japanese Patent Application No. 2020-112957 filed on June 30, 2020, and the entire disclosure of future applications is incorporated herein by reference.

This disclosure relates to a method for manufacturing a covering tool.

A covering tool used for a cutting tool or the like has a coating layer on a substrate. The coating layer is formed by a CVD method or a PVD method. Examples of the coating layer formed by the CVD method include a coating layer in which a TiN layer, a TiCN layer, and an Al ₂ O ₃ layer are sequentially laminated on a substrate.

The coating film formed by the CVD method may have a large residual stress. Ceramic particles are projected onto the coating layer to relieve the residual stress.

For example, Japanese Patent No. 4739235 (Patent Document 1) describes that the coating layer is blasted with ceramic abrasive grains.

An example of a method for manufacturing a covering tool, which is not limited to the present disclosure, is a method for manufacturing a covering tool having a substrate and a coating layer located on the substrate. The first step of preparing an untreated coating tool having an untreated coating layer on the substrate, and the second step of colliding spherical ceramic particles having a hardness (HV) of 1000 or more with the untreated coating layer. And have.

It is a perspective view which shows the covering tool of an embodiment which is not limited in this disclosure. It is sectional drawing of the II-II cross section in the covering tool shown in FIG. It is an enlarged view near the covering layer in the covering tool shown in FIG. It is an electron microscope (SEM) photograph of spherical ceramic particles. It is an electron microscope (SEM) photograph of the angular ceramic particles. It is a perspective view which shows the cutting tool of embodiment which is not limited in this disclosure.

<Manufacturing method of covering tools>
Hereinafter, a method for manufacturing the covering tool 1 according to an embodiment not limited to the present disclosure will be described in detail with reference to the drawings. However, in each of the figures referred to below, for convenience of explanation, only the main members necessary for explaining the embodiment are shown in a simplified manner. Therefore, the covering tool 1 may include any component not shown in each of the referenced figures. Further, the dimensions of the members in each drawing do not faithfully represent the dimensions of the actual constituent members and the dimensional ratio of each member.

According to the method for manufacturing the covering tool 1 of the embodiment without limitation of the present disclosure, it is easy to obtain the covering tool 1 having excellent fracture resistance. 1 to 3 show a cutting insert applicable to a cutting tool as an example of the covering tool 1. In addition to cutting tools, the covering tool 1 can be applied to, for example, wear-resistant parts such as sliding parts and dies, tools such as excavation tools and blades, and impact-resistant parts. The application of the covering tool 1 is not limited to the illustrated one.

The covering tool 1 may have a base 2 and a covering layer 3 located on the base 2.

Examples of the material of the substrate 2 include hard alloys, ceramics and metals. The hard alloy comprises, for example, WC (tungsten carbide) and, if desired, at least one selected from the group of carbides, nitrides, and carbon nitrides of

Group

4, 5, and 6 metals of the Periodic Table other than WC. Examples thereof include cemented carbide in which a hard phase is bonded with a bonded phase made of an iron group metal such as Co (cobalt) or Ni (nickel). Further, as another hard alloy, Ti-based cermet and the like may be mentioned. Examples of the ceramics include Si ₃ N ₄ (silicon nitride), Al ₂ O ₃ (aluminum oxide), diamond and cBN (cubic boron nitride). Examples of the metal may include carbon steel, high speed steel, alloy steel and the like. The material of the substrate 2 is not limited to the example.

The coating layer 3 may cover the entire surface 4 of the substrate 2, or may cover only a part of the surface 4. When the coating layer 3 covers only a part of the surface 4 of the substrate 2, it can be said that the coating layer 3 is located at least a part on the substrate 2.

The coating layer 3 may be formed by a chemical vapor deposition (CVD) method. In other words, the coating layer 3 may be a CVD film.

The coating layer 3 is not limited to a specific thickness. For example, the thickness of the covering layer 3 may be set to 1 to 30 μm. The thickness and structure of the coating layer 3 and the shape of the crystals constituting the coating layer 3 may be measured, for example, by observing a cross section using an electron microscope. Examples of the electron microscope include a scanning electron microscope (SEM) and a transmission electron microscope (TEM).

The covering tool 1 has a first surface 5 (upper surface), a second surface 6 (side surface) adjacent to the first surface 5, and a first surface 5 and a first surface, as in the case of the unrestricted example shown in FIGS. 1 and 2. A cutting edge 7 located at least a part of the ridgeline portion of the two surfaces 6 may be provided.

The first surface 5 may be a rake surface. The entire surface of the first surface 5 may be a rake surface, or a part thereof may be a rake surface. For example, the region of the first surface 5 along the cutting edge 7 may be a rake surface.

The second surface 6 may be an escape surface. The entire surface of the second surface 6 may be a flank, or a part thereof may be a flank. For example, the region of the second surface 6 along the cutting edge 7 may be a flank.

The cutting edge 7 may be located in a part of the ridgeline portion, or may be located in the entire ridgeline portion. The cutting edge 7 can be used for cutting a work material.

The covering tool 1 may have a square plate shape as in the case of the unrestricted example shown in FIG. The shape of the covering tool 1 is not limited to the square plate shape. For example, the first surface 5 may be triangular, pentagonal, hexagonal or circular. Further, the covering tool 1 may have a pillar shape.

The covering tool 1 is not limited to a specific size. For example, the length of one side of the first surface 5 may be set to about 3 to 20 mm. Further, the height from the first surface 5 to the surface (lower surface) located on the opposite side of the first surface 5 may be set to about 5 to 20 mm.

Here, the covering layer 3 may have an Al ₂ O ₃ layer 8 as in the case of the unrestricted example shown in FIG.

The Al ₂ O ₃ layer 8 may be a layer containing _{Al 2} O _{3 particles.} Further, the Al ₂ O ₃ layer 8 may be a layer containing _{Al 2} O _{3 as a main component.} The "main component" may mean a component having the largest mass% value as compared with other components. These points may be similarly defined in other layers.

The Al ₂ O ₃ layer 8 may have a first region. In the first region, the fracture toughness value may be 5 MPa · m ^0.5 or more. _{This fracture toughness value may be a value when the fracture toughness value of the Al 2} O ₃ layer 8 is measured on the surface 9 of the coating layer 3 parallel to the surface 4 of the substrate 2.

The above-mentioned "parallel" is not limited to strict parallelism, and may mean that an inclination of about ± 10 ° is allowed. The fracture toughness value shall be measured by indenting the mirrored surface with a nanoindenter and observing cracks in the obtained indentations using a field emission scanning electron microscope (FE-SEM). It may be measured with. For mirror polishing, a diamond paste with an average particle size of 1 to 3 μm manufactured by Tomei Diamond Co., Ltd. and olive oil manufactured by Sankei Sangyo Co., Ltd. adjusted to a paste concentration of 20 to 30% by mass were used. May be good. As the nano indenter, for example, an ultra-fine indentation hardness tester ENT-1100b / a manufactured by Elionix Inc. may be used for measurement. The pushing load is 700 (mN), and the indenter used for the measurement may be a Berkovich indenter ENT-20-13 manufactured by Toyo Technica Co., Ltd. The fracture toughness value may be measured according to JIS R 1607: 2015. The cracks may be observed using JSM-7100F manufactured by JEOL Ltd.

When the Al ₂ O ₃ layer 8 has the above-mentioned first region, the coating layer 3 is unlikely to be chipped, so that the chipping resistance is excellent. Incidentally, may be all the Al ₂ O ₃ layer 8 consists of a first region, a portion of the Al ₂ O ₃ layer 8 may be composed of a first region. Hereinafter, the fracture toughness value in the first region is referred to as a first fracture toughness value. The upper limit of the first fracture toughness value may be ^{10 MPa · m 0.5.}

The Al ₂ O ₃ layer 8 may have a first region on each of the first surface 5 and the second surface 6. In this case, the first surface 5 and the second surface 6 are unlikely to be damaged.

The Al ₂ O ₃ layer 8 may have a second region. _{The Al 2} O ₃ layer 8 in the covering tool 1 need not have high fracture toughness in all regions. For example, the second region may be located in a region that is not involved in cutting or a region that is involved in cutting but is not subject to a large force or impact. The region not involved in cutting may be a region separated from the cutting edge 7 in the directions of the first surface 5 and the second surface 6 by 1 mm or more. In the second region, the fracture toughness value may be less than ^{5 MPa · m 0.5.} _{This fracture toughness value may be a value when the fracture toughness value of the Al 2} O ₃ layer 8 is measured on the surface 9 of the coating layer 3 parallel to the surface 4 of the substrate 2.

The first region of the present disclosure is obtained, for example, by undergoing a blast treatment step using a spherical ceramic powder having a predetermined hardness. In the blasting process, so-called drive last or wet blast may be used. Wet blasting has the advantage of excellent handling of ceramic powder.

When the Al ₂ O ₃ layer 8 has the above-mentioned first region and the second region, the time of the blasting process can be shortened, and the covering tool 1 can be manufactured at low cost. Hereinafter, the fracture toughness value in the second region is referred to as a second fracture toughness value. The lower limit of the second fracture toughness value may be ^{0.3 MPa · m 0.5.}

When the hardness in the first region is the first hardness and the hardness in the second region is the second hardness, the second hardness may be larger than the first hardness. In this case, the wear resistance of the covering tool 1 is high.

The first hardness and the second hardness are not limited to specific values. For example, the first hardness may be set to about 10 to 30 GPa. The second hardness may be set to about 15 to 30 GPa. The first hardness and the second hardness may be measured by an indentation test using a nanoindenter in the same manner as the measurement of the fracture toughness value of _{the Al 2} O _{3 layer 8, for example.} As the nano indenter, for example, an ultra-fine indentation hardness tester ENT-1100b / a manufactured by Elionix Inc. may be used for measurement. The pushing load is 700 (mN), and the indenter used for the measurement may be a Berkovich indenter ENT-20-13 manufactured by Toyo Technica Co., Ltd.

The Al ₂ O ₃ layer 8 may have a first region on the first surface 5 or a second region on the second surface 6. In this case, the wear resistance and the fracture resistance of the covering tool 1 are high.

The coating layer 3 may have a Ti-based coating layer 10 between the substrate 2 and the Al ₂ O _{3 layer 8.} The Ti-based coating layer 10 may be a layer containing TiCN particles, TiC particles, or TiN particles. Further, the Ti-based coating layer 10 may be a layer containing TiCN as a main component.

The Ti-based coating layer 10 may have a third region. In the third region, the fracture toughness value may be 10 MPa · m ^0.5 or more. This fracture toughness value may be a value when the fracture toughness value of the Ti-based coating layer 10 is measured on the surface 9 of the coating layer 3 parallel to the surface 4 of the substrate 2.

When the Ti-based coating layer 10 has the above-mentioned third region, the coating layer 3 is unlikely to be chipped, so that the chipping resistance is excellent. In addition, all of the Ti-based coating layer 10 may be composed of the third region, or a part of the Ti-based coating layer 10 may be composed of the third region. Hereinafter, the fracture toughness value in the third region is referred to as a third fracture toughness value. The upper limit of the third fracture toughness value may be ^{20 MPa · m 0.5.}

The Ti-based coating layer 10 may have a fourth region. The Ti-based coating layer 10 in the covering tool 1 does not have to have high fracture toughness in all regions. For example, the fourth region may be located in a region that is not involved in cutting or a region that is involved in cutting but is not subject to a large force or impact. The region not involved in cutting may be a region separated from the cutting edge 7 in the directions of the first surface 5 and the second surface 6 by 1 mm or more. In the fourth region, the fracture toughness value may be less than ^{10 MPa · m 0.5.} This fracture toughness value may be a value when the fracture toughness value of the Ti-based coating layer 10 is measured on the surface 9 of the coating layer 3 parallel to the surface 4 of the substrate 2.

The third region of the present disclosure is obtained, for example, by undergoing a blast treatment step using a spherical ceramic powder having a predetermined hardness. In the blasting process, so-called drive last or wet blast may be used. Wet blasting has the advantage of excellent handling of ceramic powder.

When the Ti-based covering layer 10 has the above-mentioned third region and the fourth region, the time of the blasting step can be shortened, and the covering tool 1 can be manufactured at low cost. Hereinafter, the fracture toughness value in the fourth region is referred to as a fourth fracture toughness value. The lower limit of the fourth fracture toughness value may be ^{1.5 MPa · m 0.5.}

When the hardness in the third region is the third hardness and the hardness in the fourth region is the fourth hardness, the third hardness may be larger than the fourth hardness. In this case, the wear resistance of the covering tool 1 is high.

The third hardness and the fourth hardness are not limited to specific values. For example, the third hardness may be set to about 15 to 30 GPa. The fourth hardness may be set to about 10 to 30 GPa. The third hardness and the fourth hardness may be measured in the same manner as the first hardness and the second hardness.

The first region may be located above the third region, and the second region may be located above the fourth region. In this case, the chipping resistance is high, the time of the blasting process can be shortened, and the covering tool 1 can be manufactured at low cost.

The half width of the (104) plane of the Al ₂ O ₃ layer 8 may be 0.15 ° or more in X-ray diffraction. In this case, the coating layer 3 is less likely to be chipped, and the chipping resistance is excellent. The half width of the (104) plane of the Al ₂ O _{3 layer 8 may be measured as follows.} The (104) plane may be based on the JCPDS card number 00-010-0173. When the Al ₂ O ₃ layer 8 is exposed by the wet blast treatment, the XRD measurement may be performed on the mirror surface obtained by mirror polishing the surface of the _{exposed Al 2} O _{3 layer 8.} If the Al ₂ O ₃ layer 8 is not exposed, it continues to mirror polishing process until the Al ₂ O ₃ layer 8 is exposed, may be performed XRD measurement specular exposed in the Al ₂ O ₃ layer 8 .. The XRD measurement of the Al ₂ O ₃ layer 8 may be performed by selecting a surface having less unevenness on the surface. The XRD measurement may be performed using a MiniFlex 600 manufactured by Rigaku Corporation. The measurement conditions are that the characteristic X-ray is CuKβ ray, the output is 40 kV, 15 mA, the transmitting side solar slit is 2.5 °, the longitudinal limiting slit is 5.0 mm, the divergent slit is 0.625 °, and the scatter slit is 8.0 mm. , The light receiving side solar slit 2.5 °, the light receiving slit 13.0 mm, the step width may be 0.01 °, the measurement speed may be 2.0 ° / min, and the scan angle may be 20 ° to 90 °. The upper limit of the half width of the (104) plane of the Al ₂ O _{3 layer 8 may be 2.0 °.}

The coating layer 3 _{may have a layer other than the Al 2} O ₃ layer 8 and the Ti-based coating layer 10. Examples of the other layer may include a TiC layer and a TiN layer. Coating layer 3 is, as one non-limiting example shown in Figure 3, may be configured such that the TiN layer 11, Ti-based coating layer 10, Al ₂ O ₃ layer 8 in this order on the substrate 2 are laminated, further , The TiN layer 12 or the like may be laminated on _{the Al 2} O _{3 layer 8.} The Al ₂ O ₃ layer 8 may be in contact with the Ti-based coating layer 10. The TiN layer 11 may be referred to as the first TiN layer 11 and the TiN layer 12 may be referred to as the second TiN layer 12 for convenience.

The thickness of each of the first TiN layer 11, the Ti-based coating layer 10, the Al ₂ O ₃ layer 8 and the second TiN layer 12 is not limited to a specific value. For example, the thickness of the first TiN layer 11 may be set to 0.1 to 3.0 μm. The thickness of the Ti-based coating layer 10 may be set to 1.0 to 20 μm. The thickness of the Al ₂ O ₃ layer 8 may be set to 1.0 to 20 μm. The thickness of the second TiN layer 12 may be set to 0.1 to 10 μm.

The covering tool 1 may have a through hole 13. The through hole 13 can be used to attach a fixing screw, a clamp member, or the like when holding the covering tool 1 in the holder. The through hole 13 may be formed from the first surface 5 to the surface (lower surface) located on the opposite side of the first surface 5, or may be open in these surfaces. It should be noted that there is no problem even if the through hole 13 is configured to open in a region facing each other on the second surface 6.

When manufacturing the covering tool 1, the substrate 2 may be manufactured first. A case where a substrate 2 made of a hard alloy is produced as the substrate 2 will be described as an example. First, a metal powder, a carbon powder, or the like may be appropriately added and mixed with an inorganic powder such as a metal carbide, a nitride, a carbonitride, or an oxide that can form a substrate 2 by firing to obtain a mixed powder. Next, this mixed powder may be molded into a predetermined tool shape by a known molding method such as press molding, casting molding, extrusion molding, cold hydrostatic press molding, or the like to obtain a molded product. Then, the obtained molded product may be fired in a vacuum or in a non-oxidizing atmosphere to obtain a substrate 2. The surface 4 of the substrate 2 may be subjected to a polishing process or a honing process.

Next, the coating film 3 may be formed on the surface 4 of the obtained substrate 2 by a CVD method. Further, the coated layer 3 formed on the film may be subjected to a wet blast treatment. Hereinafter, the covering layer 3 and the covering tool 1 in a state before the wet blast treatment is referred to as an untreated coating layer and an untreated covering tool. The untreated coating layer subjected to the wet blast treatment is referred to as a coating layer 3, and the untreated coating tool is referred to as a coating tool 1. The step before the wet blast treatment may be said to be the first step of preparing an untreated coating tool having an untreated coating layer on the substrate 2.

As an untreated coating layer, for example, it may be formed the first 1TiN layer 11, Ti-based coating layer 10, Al ₂ O ₃ layer 8 in this order on the substrate 2. Further, a _second TiN layer 12 or the like may be formed on the Al 2 O _{3 layer 8.}

The first TiN layer 11 may be formed as follows. First, as the reaction gas composition, a _{mixed gas consisting of titanium tetrachloride (TiCl 4} ) gas in an amount of 0.1 to 10% by volume, nitrogen (N ₂ ) gas in an amount of 10 to 60% by volume, and the rest being hydrogen (H ₂ ) gas is used. You may adjust. Then, this mixed gas may be introduced into the chamber, the temperature may be set to 800 to 1010 ° C., the pressure may be set to 10 to 85 kPa, and the first TiN layer 11 may be formed into a film. This film forming condition is also applicable to the second TiN layer 12.

The Ti-based coating layer 10 may be formed as follows. First, as the reaction gas composition, titanium tetrachloride (TiCl ₄ ) gas is 0.1 to 10% by volume, acetonitrile (CH ₃ CN) gas is 0.1 to 3.0% by volume, and the rest is hydrogen (H ₂ ) gas. The mixed gas composed of may be adjusted. Then, this mixed gas may be introduced into the chamber, the temperature may be set to 800 to 1050 ° C., the pressure may be set to 5 to 30 kPa, and the Ti-based coating layer 10 may be formed.

The Al ₂ O ₃ layer 8 may be formed as follows. First, as the reaction gas composition, aluminum trichloride (AlCl ₃ ) gas is 0.5 to 5% by volume, hydrogen chloride (HCl) gas is 0.5 to 3.5% by volume, and carbon dioxide (CO ₂ ) gas is 0. A mixed gas consisting of 5 to 5% by volume, _{0.5% by volume or less of hydrogen sulfide (H 2} S) gas, and the balance of hydrogen (H ₂ ) gas may be adjusted. Then, this mixed gas may be introduced into the chamber, the temperature may be set to 930 to 1010 ° C., the pressure may be set to 5 to 10 kPa, and the Al ₂ O ₃ layer 8 may be formed.

Next, a step of applying a wet blast treatment to the formed untreated coating layer may be performed. This step may be a second step of colliding spherical ceramic particles having a hardness (HV) of 1000 or more with the untreated coating layer. HV (Vickers hardness) may be measured in accordance with JIS Z 2244: 2009. The upper limit of the hardness (HV) of the spherical ceramic particles may be 2500.

The hardness of media such as spherical ceramic particles may be measured by hardness measurement by a load-unloading test. In measuring the hardness, a cured product prepared by mixing the media and the embedded resin and then curing the mixture may be used. The surface of the cured product may be polished to measure the hardness of the medium exposed on the polished surface. As the embedded resin, for example, Technovit 4004 manufactured by Kulzer may be used. The media to be measured and the embedded resin may be mixed at a ratio of 3: 1 (mass ratio) to form a cured product, and the surface may be polished. After polishing, the hardness may be measured on the exposed portion of the media of the cured product. The measurement may be performed using a dynamic ultrafine hardness tester DUH-211S. Measured under the conditions that the measuring indenter has a ridge angle of 115 °, a triangular cone indenter (made of diamond), a test force of 49 (mN), a load speed of 2.665 (mN / sec), and a holding time of 5 seconds. You may. The number of measurements may be 10 points, and the average value thereof may be measured.

The second step may be performed on the entire surface of the untreated coating layer, or may be performed on a part of the surface. In the portion of the untreated coating layer where the second step has been performed, the Al ₂ O ₃ layer 8 tends to have a first region, and the Ti-based coating layer 10 tends to have a third region. The second step was not part of the untreated coating layer is liable to the Al ₂ O ₃ layer 8 is to have a second region, also, Ti-based coating layer 10 is liable to have a fourth region.

In the wet blast treatment, a blast liquid containing spherical ceramic particles in the liquid may be projected onto the untreated coating layer. The blast liquid is also called a slurry. As the liquid, for example, water may be used.

The spherical ceramic particles may mean that they are not obtained by crushing a raw material. In order to distinguish it from spherical ceramic particles, the ceramic particles obtained by crushing the raw material may be referred to as angular ceramic particles. FIG. 4 shows a photograph of spherical ceramic particles. Further, FIG. 5 shows a photograph of the angular ceramic particles. The spherical ceramic particles may have a specific gravity of 6 g / cm ³ or less. Spherical ceramic particles having a specific gravity of 6 g / cm ³ or less are suitable for wet blasting because they have a relatively small specific gravity and are easily dispersed in water. For example, _{the specific gravity of Al 2} O ₃ particles is about 4 g / cm ³ .

As shown in the photograph shown in FIG. 5, the angular ceramic particles may be amorphous and have angles. The angular ceramic particles may be produced by crushing raw material particles or the like, or may have crushed surfaces and corners formed in the pulverization step. It is the angular ceramic particles that are used in the conventional wet blasting process.

On the other hand, as shown in the photograph shown in FIG. 4, the spherical ceramic particles may have a shape close to a true sphere without any corners. The shape of the spherical ceramic particles does not have to be a true sphere, and some deformation from the sphere is acceptable as long as there are no crushed surfaces or sharp angles.

Spherical metal particles may be mentioned as similar in shape to the spherical ceramic particles. Spherical metal particles are similar in shape to spherical ceramic particles, but have a heavier specific gravity and are softer than spherical ceramic particles. For example, the specific gravity of the spherical metal particles is 7 to 8 g / cm ³ . Further, the hardness (HV) of the spherical metal particles is less than 1000. Although it is presumed that this is due to such characteristics, when spherical metal particles are used, it is difficult to obtain a covering tool 1 having a first region or a third region. Further, due to the heavy specific gravity, the spherical metal particles are difficult to disperse in water and are not suitable for wet blasting.

For the same reason, even if it is a spherical ceramic particle, if it contains a large amount of glass beads having a hardness (HV) of less than 1000 or a glass component, it is difficult to obtain a covering tool 1 having a first region or a third region.

In the wet blast treatment, spherical ceramic particles of various sizes can be used. When spherical ceramic particles having a large average particle size are used, the blast time is likely to be shortened. The average particle size of the spherical ceramic particles may be 200 μm or less.

Further, the average particle size of the spherical ceramic particles may be 30 μm or more and 100 μm or less. When spherical ceramic particles in this range are used, various untreated coating layers can be blasted with good reproducibility.

The average particle size of the spherical ceramic particles may be measured by a laser diffraction method. When the spherical ceramic particles and the angular ceramic particles are mixed, the blast solution is dried, the spherical ceramic particles are extracted by the SEM photograph, and the circle of 100 individual spherical ceramic particles obtained from the photograph. It may be an average value of equivalent diameters.

The average circularity of the spherical ceramic particles may be 0.82 or more. In particular, the average circularity of the spherical ceramic particles may be 0.88 or more. In this case, the chipping resistance of the coated tool to be manufactured is high. The upper limit of the average circularity may be 0.98.

The average circularity may be measured as follows. First, after taking a particle image with SEM or TEM, the projected area (S) and peripheral length (L) of the particles are measured using image analysis software (for example, "Mac-View Version.4" manufactured by Mountech). It may be measured. Next, the obtained measured value may be applied to the formula: 4πS / L ² to calculate the circularity. The circularity may be calculated for 100 arbitrarily selected particles, and the average value thereof may be used as the average circularity.

Examples of the material of the spherical ceramic particles include Al ₂ O ₃ , ZrO ₂ and SiC. When spherical ceramic particles made of a material having a large specific gravity are used, the average particle size may be reduced. When spherical ceramic particles made of a material having a small specific gravity are used, the average particle size may be increased.

A blast liquid may be prepared by containing 10 to 40% by volume of spherical ceramic particles with respect to water.

The projection conditions of the blast liquid may be a projection pressure of 0.15 to 0.30 MPa and a projection time of 0.4 to 10.0 seconds. If the projection time of the blast liquid exceeds 10.0 seconds, the untreated coating layer tends to peel off, which is not suitable. When the blast liquid is projected onto the untreated coating layer, _{at least a part of the Al 2} O ₃ layer 8 may remain.

For example, the covering tool 1 can be manufactured by the above-mentioned process. The manufactured covering tool 1 has excellent fracture resistance.
The blast liquid may partially contain angular ceramic particles. In such a case, 50% by volume or more of the ceramic particles may be spherical ceramic particles.

Before projecting the blast liquid containing the spherical ceramic particles, the blast liquid containing the angular ceramic particles may be projected. Further, the blast liquid containing the angular ceramic particles may be projected after the blast liquid containing the spherical ceramic particles is projected. The fracture toughness value of the coating layer 3 increased by projecting the blast solution containing the spherical ceramic particles is unlikely to decrease even when the blast solution containing the angular ceramic particles is projected.

When projecting a blast liquid containing spherical ceramic particles on the untreated coating layer, for example, a commercially available wet blasting apparatus may be used.

In the untreated coating tool, the untreated coating layer may have tensile stress. The tensile stress is not limited to a specific value. The absolute value of the tensile stress may be set to about 50 to 500 MPa.

The untreated coating layer may have compressive stress. The compressive stress is not limited to a specific value. The absolute value of the compressive stress may be set to about 50 to 2000 MPa.

The tensile stress and the compressive stress may be measured by the sin2ψ method using an X-ray stress measuring device (XRD). When measuring the residual stress, the Al ₂ O ₃ layer 8 may be measured by selecting the (116) plane of the α-type Al ₂ O _3. The Ti-based coating layer 10 may be measured by selecting the (422) plane of TiCN.

In the obtained covering tool 1, the area including the cutting edge 7 may be polished. As a result, the region including the cutting edge 7 becomes smooth. As a result, welding of the work material is suppressed, and the cutting edge 7 has high fracture resistance.

<Cutting tool>
The obtained covering tool 1 can be applied to a cutting tool. Next, the cutting tool 101 of the embodiment without limitation of the present disclosure will be described in detail with reference to FIG. 6, taking as an example the case where the covering tool 1 is provided.

The cutting tool 101 includes a holder 102 having a length extending from the first end 102a to the second end 102b and having a pocket 103 located on the side of the first end 102a, as in an unrestricted example shown in FIG. It may have a covering tool 1 located in the pocket 103. When the cutting tool 101 has the covering tool 1, since the covering tool 1 has excellent fracture resistance, stable cutting can be performed for a long period of time.

The pocket 103 may be a portion where the covering tool 1 is mounted. The pocket 103 may be open on the outer peripheral surface of the holder 102 and the end surface on the side of the first end 102a.

The covering tool 1 may be mounted in the pocket 103 so that the cutting edge 7 protrudes outward from the holder 102. Further, the covering tool 1 may be attached to the pocket 103 by the fixing screw 104. That is, the covering tool 1 is formed by inserting the fixing screw 104 into the through hole 13 of the covering tool 1, inserting the tip of the fixing screw 104 into the screw hole formed in the pocket 103, and screwing the screw portions together. It may be attached to the pocket 103. A sheet may be sandwiched between the covering tool 1 and the pocket 103.

Examples of the material of the holder 102 include steel and cast iron. When the material of the holder 102 is steel, the toughness of the holder 102 is high.

In the example shown in FIG. 6, a cutting tool 101 used for so-called turning is illustrated. Examples of the turning process include inner diameter processing, outer diameter processing, grooving processing, and the like. The application of the cutting tool 101 is not limited to turning. For example, there is no problem even if the cutting tool 101 is used for milling.

Hereinafter, the present disclosure will be described in detail with reference to examples, but the present disclosure is not limited to the following examples.

[Sample No. 1-11]
<Manufacturing of covering tools>
First, a substrate was prepared. Specifically, with respect to the average particle diameter 1.2μm of WC powder, average particle metal Co powder of diameter 1.5 [mu] m 6 wt%, 2.0 wt% of TiC (titanium carbide) powder, Cr ₃ C ₂ (Chromium carbide) powder was added at a ratio of 0.2% by mass and mixed to prepare a mixed raw material powder. Next, the mixed raw material powder was press-molded and molded into a cutting tool shape (CNMG120408) to obtain a molded body. The obtained molded product was subjected to a binder removal treatment and fired at 1400 ° C. for 1 hour in a vacuum of 0.5 to 100 Pa to prepare a substrate made of cemented carbide. The rake face (first surface) of the produced substrate was brushed to perform cutting edge treatment (R honing).

Next, an untreated coating layer was formed on this substrate. Specifically, a first TiN layer, a Ti-based coating layer, an Al ₂ O ₃ layer, and a second TiN layer were formed on the substrate in this order from the side of the substrate. The film formation conditions and thickness are as follows. The thickness is a value obtained by cross-sectional measurement by SEM.

(1st TiN layer)
TiCl ₄ gas: 1.0% by volume
N ₂ gas: 55.0% by volume
H ₂ gas: remaining temperature: 850 ° C
Pressure: 16kPa
Thickness: 1.0 μm

(Ti-based coating layer)
TiCl ₄ gas: 7.0% by volume
CH ₃ CN gas: 0.5% by volume
H ₂ gas: remaining temperature: 850 ° C
Pressure: 10 kPa
Thickness: 7.0 μm

(Al ₂ O ₃ layer)
AlCl ₃ gas: 4.2% by volume
HCl gas: 0.9% by volume
CO ₂ gas: 4.5% by volume
H ₂ S gas: 0.3% by volume
H ₂ gas: remaining temperature: 950 ° C
Pressure: 9kPa
Thickness: 8.0 μm

(2nd TiN layer)
TiCl ₄ gas: 3.0% by volume
N ₂ gas: 40.0% by volume
H ₂ gas: remaining temperature: 1010 ° C
Pressure: 30 kPa
Thickness: 2.0 μm

_{Next, as the medium, 25% by volume of spherical Al 2} O ₃ particles having an average particle size shown in Table 1, spherical particles made of zircon (ZrSiO ₄ ), and angular Al ₂ O ₃ particles are contained in water. The blast solution was adjusted in this way. The hardness (HV) of the media is a value measured as follows.

(Media hardness)
The hardness of the media used in the blasting process was measured by measuring the hardness by the load-unloading test. First, the media to be measured was fixed with an embedded resin (Technovit4004 manufactured by Kulzer), and the surface was polished. _{Specifically, 3 g of Al 2} O ₃ powder is added to 1 g of a resin obtained by mixing a liquid curing resin and a curing agent at a ratio of 3: 1 (mass ratio), and after mixing, the temperature is 1 hour at room temperature (23 ° C). It was cured to some extent to obtain a cured product. Then, the procedure of polishing this cured product was used. After polishing, the hardness was measured on the exposed portion of the cured media. The measurement was performed using a dynamic ultrafine hardness tester DUH-211S. Measured under the conditions that the measuring indenter has a ridge angle of 115 °, a triangular cone indenter (made of diamond), a test force of 49 (mN), a load speed of 2.665 (mN / sec), and a holding time of 5 seconds. did. The number of measurements was 10 points, and the average value was measured.

The adjusted blast liquid was projected onto the untreated coating layer at the time shown in Table 1 at a pressure (projection pressure) of compressed air of 0.2 MPa to obtain a coating tool. The blast liquid was projected onto the regions involved in cutting on the first and second surfaces. The region involved in cutting was set to a region of less than 1 mm in the direction of the first surface and the second surface from the cutting edge.

<Evaluation>
The first to fourth fracture toughness values and the first to fourth hardness of the obtained coated tool were measured. In addition, the half width of the (104) plane of the region involved in cutting was measured. Furthermore, cutting evaluation was performed using the obtained covering tool, and the fracture resistance was evaluated. The measurement method is shown below, and the results are shown in Tables 2 and 3.

(1st to 4th fracture toughness values)
A indentation test was performed on the mirrored surface with a nanoindenter, and cracks were observed in the obtained indentations using a field emission scanning electron microscope (FE-SEM), and the fracture toughness value was measured. As the nano indenter, the measurement was performed using an ultra-fine indentation hardness tester ENT-1100b / a manufactured by Elionix Inc. The indentation load was 700 (mN), and the indenter used for the measurement was measured using a Berkovich indenter ENT-20-13 manufactured by Toyo Technica Co., Ltd. The fracture toughness value was measured according to JIS R 1607: 2015. The cracks were observed using JSM-7100F manufactured by JEOL Ltd.

When the Al ₂ O ₃ layer was exposed by the wet blast treatment, the fracture toughness value was measured on the mirror surface obtained by mirror polishing the surface of the _{exposed Al 2} O _{3 layer.} If the Al ₂ O ₃ layer is not exposed, continues to mirror polishing process until the Al ₂ O ₃ layer is exposed, it was measured fracture toughness value specular exposed in the Al ₂ O ₃ layer.

The fracture toughness value of the Ti-based coating layer was also measured on the mirror surface of the exposed Ti-based coating layer after mirror polishing was performed from the surface of the coating layer until the Ti-based coating layer was exposed.

For mirror polishing, a diamond paste having an average particle size of 1.4 μm manufactured by Tomei Diamond Co., Ltd. and olive oil manufactured by Sankei Sangyo Co., Ltd. adjusted to have a paste concentration of 25% by mass were used. .. Further, mirror polishing was performed so that the mirror surface was parallel to the surface of the substrate.

(1st to 4th hardness)
Measured by indentation test using nano indenter. As the nanoindenter, an ultrafine indentation hardness tester ENT-1100b / a manufactured by Elionix Inc. was used. The pushing load was 700 (mN), and the indenter used for the measurement was a Berkovich indenter ENT-20-13 manufactured by Toyo Technica Co., Ltd.

(Half width at half maximum of the (104) plane of the region involved in cutting)
The half width of the (104) surface of the region involved in the cutting of the wet blasted surface was measured. The (104) plane of the Al ₂ O ₃ layer was based on the JCPDS card number 00-010-0173. When the Al ₂ O ₃ layer was exposed by the wet blast treatment, XRD measurement was performed on the mirror surface obtained by mirror polishing the surface of the _{exposed Al 2} O _{3 layer.} When the Al ₂ O ₃ layer was not exposed, the mirror polishing process was continued until _{the Al 2} O ₃ layer was exposed, and XRD measurement was performed on the exposed mirror surface of the _{Al 2} O _{3 layer.} The XRD measurement of the Al ₂ O ₃ layer was performed by selecting a surface having less unevenness on the surface. The XRD measurement was performed using a MiniFlex 600 manufactured by Rigaku Co., Ltd. The measurement conditions are that the characteristic X-ray is CuKβ ray, the output is 40 kV, 15 mA, the transmitting side solar slit is 2.5 °, the longitudinal limiting slit is 5.0 mm, the divergent slit is 0.625 °, and the scatter slit is 8.0 mm. The solar slit on the light receiving side was 2.5 °, the light receiving slit was 13.0 mm, the step width was 0.01 °, the measurement speed was 2.0 ° / min, and the scan angle was 20 ° to 90 °.

(Cutting evaluation)
The intermittent cutting test was performed under the following conditions.
Work material: Carbon steel for machine structure (S45C 16-grooved steel material)
Tool shape: CNMG120408
Cutting speed: 48m / min Feeding speed: 0.27mm / rev
Notch: 1.0 mm
Others: Use of water-soluble cutting fluid Evaluation item: Measure the number of impacts leading to defects

Sample No. No. 1 did not perform the treatment of projecting the blast liquid onto the untreated coating layer. In other words, sample No. Reference numeral 1 denotes a coating tool in which a coating layer is simply formed on a substrate. Sample No. The fracture toughness value of the Al ₂ O ₃ layer of No. 1 was 0.8 MPa · m ^{0.5 on} both the first and second surfaces.

Sample No. Reference numeral 2 is a projection of the blast liquid containing the angular ceramic particles onto the first surface and the second surface. Sample No. In No. 2, the fracture toughness value of the _{Al 2} O _{3 layer was the untreated sample No.} It was slightly higher than 1, and was 1.5 MPa · m ^{0.5 on} both the first and second surfaces.

Sample No.

Reference numerals

3 and 4 are _{projections of a blast liquid containing spherical zircon (ZrSiO 4} ) particles onto the first and second surfaces. Sample No. In 3 and 4, the fracture toughness value of the _{Al 2} O _{3 layer was the untreated sample No.} Slightly larger than 1, the higher was 1.5 MPa · m ^0.5 or 2.0 MPa · m ^0.5 in both the first and second surfaces.

Sample No. The fracture toughness values of the Al ₂ O _{3 layers 1 to 4 were all low.}

On the other hand, the sample No. which is the covering tool of the present disclosure. The Al ₂ O ₃ layer of 5-11, fracture toughness value has an area of 5.0 MPa · m ^0.5 or more or 6.5 MPa · m ^0.5, and excellent chipping resistance.

In addition, sample No. _{Spherical Al 2} O ₃ particles in 5 to 11 and sample No. The average circularity was measured for the angular Al ₂ O _{3 particles in 2.} Specifically, first, after taking a particle image with SEM, the projected area (S) and the peripheral length (L) of the particles are used using image analysis software (“Mac-View Version.4” manufactured by Mountech). Was measured. Next, the obtained measured value was applied to the formula: 4πS / L ² to calculate the circularity. The circularity was calculated for 100 arbitrarily selected particles, and the average value was taken as the average circularity. The measurement results of the average circularity are as follows.

(Average circularity)
Sample No. _{Spherical Al 2} O ₃ particles in 5 to 11: 0.90
Sample No. Square Al ₂ O ₃ particles in 2: 0.74

1 ... Covering tool 2 ... Base 3 ... Covering layer 4 ... Surface 5 ... First surface 6 ... Second surface 7 ... Cutting edge 8 ... Al ₂ O ₃ Layer 9 ... Surface 10 ... Ti-based coating layer 11 ... TiN layer (first TiN layer)
12 ... TiN layer (second TiN layer)
13 ... Through hole 101 ... Cutting tool 102 ... Holder 102a ... First end 102b ... Second end 103 ... Pocket 104 ... Fixing screw

Claims

With the substrate
A method for manufacturing a coating tool having a coating layer located on the substrate.
The first step of preparing an untreated coating tool having an untreated coating layer on the substrate, and
For the untreated coating layer
A method for manufacturing a covering tool, comprising a second step of colliding spherical ceramic particles having a hardness (HV) of 1000 or more.
The method for manufacturing a covering tool according to claim 1, wherein the average particle size of the spherical ceramic particles is 30 μm or more and 100 μm or less.
The method for manufacturing a covering tool according to claim 1 or 2, wherein in the untreated covering tool, the untreated covering layer has a tensile stress.