JP2005344148A - Wear-resistant film, and surface-coated cutting tool using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film capable of enhancing the wear resistance and heat resistance of a cutting tool or the like, in particular, wear resistance, slidability and chipping resistance at a high temperature, and a tool with the film coated thereon. <P>SOLUTION: The wear-resistant film consists of metal elements selected from the group consisting of Cr, Al and Si, and one or more elements of C, N or O, and has at least one layer consisting of a compound containing ≥ 0.001 atm.% and <5 atm.% Ar atoms. Projections of ≥1 μm diameter and ≥1 μm height are present at a density of below 10 in number on the average in the range of 100 μm×100 μm on the surface of the wear-resistant film. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wear-resistant coating used for cutting tools, wear-resistant tools, machine parts, sliding parts, electrical / electronic parts, and the like, and a surface-coated cutting tool using the same.

  Recent trends in cutting tools include zero-emission processing from the viewpoint of global environmental protection, the diversification of work materials such as heat-resistant alloys and Pb-less alloys, and further improvement in machining efficiency. Therefore, the cutting edge temperature tends to become higher due to the fact that the cutting speed and the feeding speed are higher, and the characteristics required for the tool material are becoming stricter.

  In particular, the required characteristics of the tool material include not only the stability of the coating at high temperatures (oxidation resistance and coating adhesion), but also the wear resistance related to the life of the cutting tool, that is, the improvement in hardness and lubrication of the coating at high temperatures. The lubrication characteristics of coatings that change to oils are becoming more important.

Conventionally, in tools, molds, sliding parts and the like, TiCN, TiAlN, TiSiN, and Al ₂ O ₃ are applied to the surface of a substrate by PVD or CVD in order to improve wear resistance, heat resistance, and lubricity. It has become common to form one or a plurality of layers of a compound comprising such as above and coat the surface of the tool or the like.

  Of these, TiN and TiCN are mainly used as wear-resistant coatings, but wear-resistant coatings using these are inferior in oxidation resistance, so that they are resistant in environments where sliding surfaces are exposed to high temperatures. Oxidative wear of the wearable coating is a problem.

  In order to solve this problem, a coating made of a TiAlN or TiSiN material having better oxidation resistance has been developed, which makes it possible to use it in an environment at a high temperature and extend its life. However, since the coating contains Ti in the coating, the TI component is oxidized at the time of cutting or the like, which is problematic for use near 1000 ° C.

In addition, a film using Al ₂ O ₃ is generally widely used and excellent in heat resistance, but it is necessary to set the temperature to 1000 ° C. or higher when forming the film, and can be applied to this environment. A base material will be limited.

  In order to solve these problems, the following Patent Document 1 discloses a composite coating using an AlCrN material, and the following Patent Document 2 discloses a coating made of an AlCrSiN material. These coatings have high hardness and excellent wear resistance and oxidation resistance at 1000 ° C. or higher, so that they are effective in suppressing oxidative wear in a high temperature environment.

However, the coatings described in Patent Documents 1 and 2 below have problems in welding resistance and fracture resistance. Especially in cutting tools, due to recent demands for high-speed / high-efficiency machining, the tool blade edge becomes hotter and the sliding environment with the work material is severe, so that the welding of the chips becomes severe and the load on the blade edge As a result, the cutting edge is a big problem.
Japanese Patent Laid-Open No. 10-25566 Japanese Patent Laid-Open No. 2003-321764

  The present invention has been made in order to solve the above-described problems of the prior art, and its purpose is wear resistance and heat resistance of cutting tools and the like, in particular, wear resistance at high temperatures, slidability and chipping resistance. And a tool coated with the coating.

  The present invention comprises a metal element selected from the group consisting of Cr, Al and Si, and one or more elements of C, N or O, and further 0.001 atomic% or more and less than 5 atomic% A wear-resistant coating comprising one or more layers composed of a compound containing Ar atoms, wherein a projection having a diameter of 1 μm or more and a height of 1 μm or more is formed on the surface of the wear-resistant coating. Provided is an abrasion-resistant coating film characterized by being present in an average of less than 10 pieces within a range of 100 μm × 100 μm on the surface of the conductive coating film.

Preferably, among the constructed layer from said compound, the composition of elements except for Ar _{atoms, (Cr 1-x-y} Al x Si y) (C u N 1-u-v O v) ( where 0 0.2 ≦ x ≦ 0.75, 0 ≦ y ≦ 0.2, x + y ≦ 0.75, 0 ≦ u ≦ 0.5, 0 ≦ v ≦ 0.2, u + v ≦ 0.6).

  Preferably, the crystal structure of the layer composed of the compound is a NaCl-type crystal structure.

  Preferably, the crystal structure of the layer composed of the compound includes a NaCl-type crystal structure and an amorphous structure.

  Preferably, in the layer composed of the compound, the layer thickness per layer is 0.1 μm or more and 10 μm or less.

  Preferably, according to a nanoindentation method that is performed by applying a controlled indentation load so that the indentation depth is 1/10 or less of the total thickness of the layer composed of the compound. In the hardness test, when the maximum indentation depth is hmax and the indentation depth after unloading is hf, (hmax−hf) / hmax is 0.2 or more and 0.7 or less.

  Preferably, according to a nanoindentation method that is performed by applying a controlled indentation load so that the indentation depth is 1/10 or less of the total thickness of the layer composed of the compound. In the hardness test, the hardness is 20 GPa or more and 50 GPa or less.

  Preferably, the residual compressive stress is -6 GPa or more and 0 GPa or less.

  The present invention also provides a surface-coated cutting tool characterized in that the above-mentioned wear-resistant coating is coated on the surface of a substrate.

  Preferably, the base material is made of WC-based cemented carbide, cermet, high speed steel, ceramics, cubic boron nitride sintered body, diamond sintered body, silicon nitride sintered body, or aluminum oxide and titanium carbide. One of the substrates.

  Preferably, the abrasion-resistant film is formed on the substrate surface using a physical vapor deposition method.

  Preferably, the physical vapor deposition method is an unbalanced magnetron sputtering method, and the method includes a step of applying a negative bias voltage to the substrate.

  According to the wear-resistant member and the surface-coated cutting tool using the wear-resistant member of the present invention, it has excellent welding resistance, wear resistance, heat resistance, peeling resistance, and chipping resistance, and therefore has good characteristics over a long period of time. Can be maintained.

  According to the wear-resistant coating film of the present invention, it comprises a metal element selected from the group consisting of Cr, Al, and Si, and one or more elements of C, N, or O, and further 0.001 atom. % Of an abrasion-resistant film comprising one or more layers composed of a compound containing Ar atoms of not less than 5% and less than 5 atomic%, and having a diameter of 1 μm or more and a height of 1 μm or more A certain number of protrusions are present in an average of less than 10 in the range of 100 μm × 100 μm on the surface of the wear-resistant coating.

  As described in the above prior art, a nitride of CrAl or CrAlSi is a compound having excellent oxidation resistance and wear resistance. However, in a high temperature environment, it is inferior in slidability. The target material) is welded to the surface of the coating, and when the welded counterpart material is removed, the coating is also removed at the same time. In addition, at the cutting edge of the cutting tool, the welding of the work material, which is the counterpart material, may not fall on the film but may fall off to a part of the base material.

  The film and / or the substrate falling off due to such welding can be suppressed by the wear-resistant coating of the present invention. According to the wear-resistant coating film of the present invention, since the average number of protrusions having a diameter of 1 μm or more and a height of 1 μm or more within the range of 100 μm × 100 μm is less than 10 on the surface of the coating, the above-mentioned dropout is prevented. Can extend the life of the tool. This is because the welding of the counterpart material is preferentially generated on the sharp projections on the surface of the coating, so that the welding is suppressed by making the coating surface smoother.

  In the present invention, it is preferable that the number of protrusions is as small as possible. However, since it may be unreasonable from the viewpoint of manufacturing cost to completely smooth the coated surface, there may be several protrusions. On the other hand, if the number of the protrusions is 10 or more on average, the welding resistance performance is extremely lowered, which is not preferable. More preferably, the average number of protrusions having a diameter of 1 μm or more and a height of 1 μm or more in the range of 100 μm × 100 μm on the surface of the coating is less than 5.

  In the present invention, in the layer composed of a compound constituting the abrasion-resistant film, the compound is a metal element selected from the group consisting of Cr, Al and Si, and any one of C, N or O It consists of the above elements. Thus, by including any one or more elements of C, N, or O, the performance of the compound can be improved as compared with the case of using a simple nitride. Specifically, by containing C (carbon), the coefficient of friction and slidability can be improved, and the film hardness and wear resistance can also be improved. Further, by containing oxygen (O), the oxidation resistance is further improved and the chemical stability is increased. Therefore, the welding with the counterpart material due to the chemical reaction is reduced, and the welding resistance is improved.

  Here, including one or more layers composed of a compound means that one or more layers having different compositions of the compound are laminated to constitute a part or all of the wear-resistant coating. In the case of only one layer, a part or the whole of the abrasion-resistant film is formed by a layer made of a compound having one kind of composition.

  In the wear-resistant coating film of the present invention, in a layer composed of a compound, Ar atoms in the compound are within a range of 0.001% or more and less than 5% in atomic percent with respect to the entire compound layer per layer. It is preferable to include. This is because the inclusion of Ar atoms significantly improves the toughness of the coating and prevents the film from dropping off due to the loss of the coating. In particular, even when the mating material is welded to a small amount of protrusions existing within the above range, the coating and / or the base material can be prevented from falling off, and the life can be greatly extended by a synergistic effect with the welding resistance. Can do.

  If the above-mentioned Ar atom is less than 0.001% in atomic%, there is a possibility that sufficient film toughness cannot be obtained and the effect of preventing the film deficiency cannot be obtained. Moreover, when it exceeds 5 atomic%, there exists a possibility of deteriorating the characteristics of compounds, such as film hardness. More preferably, the atomic% is 0.01% or more and less than 1%.

In the present invention, in the layer composed of the compound, the atomic composition excluding Ar is (Cr _1-xy Al _x Si _y ) (C _u N _1-uv O _v ) (provided that 0. 2 ≦ x ≦ 0.75, 0 ≦ y ≦ 0.2, x + y ≦ 0.75, 0 ≦ u ≦ 0.5, 0 ≦ v ≦ 0.2, u + v ≦ 0.6). If the Al composition is less than 0.2, that is, x is less than 0.2, it is difficult to obtain desired heat resistance and hardness. On the other hand, when the Al composition exceeds 0.75, that is, when x exceeds 0.75, the hardness is lowered, so that the wear resistance may be deteriorated. More preferably, 0.55 ≦ x ≦ 0.75.

  In addition, it is preferable to include silicon (Si) in the layer composed of the compound because the structure of the layer composed of the compound becomes dense and the oxidation resistance is improved. The Si is preferably contained in a range of 0 to 0.2 in terms of composition ratio. If it exceeds 0.2, the chemical stability is lost, and there is a risk that the tendency to react with the mating material at a high temperature to increase the chemical wear may be increased. More preferably, it is 0.05 or more and 0.15 or less.

  Moreover, it is preferable at the point which heat resistance and slidability improve by containing chromium (Cr) in the layer comprised from the said compound. The Cr is preferably contained in a composition ratio of 0.25 or more. If it is less than 0.25, it is difficult to ensure the hardness of the coating, and the wear resistance may be deteriorated.

  Moreover, in the layer comprised from the said compound, it is preferable to contain C in the range of 0 or more and 0.5 or less by composition ratio. If it exceeds 0.5, the hardness of the coating increases, but the toughness is lost and the film tends to be lost. More preferably, it is 0 or more and 0.3 or less.

  Moreover, in the layer comprised from the said compound, it is preferable to contain O in the range of 0 or more and 0.2 or less by composition ratio. When it exceeds 0.2, the hardness of the coating film is lowered and the wear resistance may be deteriorated. More preferably, it is 0 or more and 0.1 or less.

  Moreover, in the layer comprised from the said compound, it is preferable to contain N in the range of 0.4 or more by composition ratio. If it is less than 0.4, the balance between wear resistance and chemical stability is lacking, and as a result, the application range of the wear resistant member may be narrowed. More preferably, it is 0.5 or more.

  In the present invention, the crystal structure can be controlled by controlling the atomic composition and formation conditions in the layer composed of the compound as described above. Here, from the viewpoint of ensuring the toughness of the cutting edge of a coating film or a tool, it is preferable to have a NaCl type crystal structure with excellent mechanical properties.

  Further, from the viewpoint of ensuring wear resistance and oxidation resistance, the crystal structure of the compound is preferably a structure in which a NaCl-type crystal structure and an amorphous structure are mixed. In particular, the NaCl-type crystallized portion is a nano-sized fine crystal of a compound mainly composed of Cr and Al, and a more excellent effect can be obtained when mixed with an amorphous portion mainly composed of Si. By using such a coating structure, the welding resistance is further improved.

  In this invention, it is preferable that the layer thickness per layer comprised from a compound is the range of 0.1 micrometer or more and 10 micrometers or less. If it is less than 0.1 μm, it is difficult to achieve the desired wear resistance, and if it exceeds 10 μm, the peel resistance of the coating is lowered. More preferably, it is 0.5 μm or more and 5 μm or less.

  In the present invention, the total layer thickness of the layer composed of the compound is preferably in the range of 0.1 μm to 20 μm. If the thickness is less than 0.1 μm, the desired wear resistance may not be obtained. If the thickness exceeds 20 μm, the toughness of the film is low, which may cause a problem that the film tends to be chipped. More preferably, it is 0.7 μm or more and 7 μm or less.

  In the wear resistant coating of the present invention, in addition to the layer composed of the above-mentioned compound, from the viewpoint of improving the adhesion between the compound layer and the substrate, an intermediate is provided between the compound layer and the substrate. It is preferable to provide a layer. The intermediate layer is preferably composed of TiN, TiCrN, TiAlN, or the like. Moreover, it is preferable that the layer thickness of the said intermediate | middle layer is the range of 0.1 micrometer or more and 5 micrometers or less. If the thickness is less than 0.1 μm, the effect may not be obtained. Further, if the thickness exceeds 5 μm, the ratio of the intermediate layer in the entire film increases, which may cause a problem that the wear resistance and weldability of the entire film deteriorate.

  In the wear resistant coating of the present invention, a surface layer may be provided on the outer side or the inner side of one or more layers composed of the compound layers. When the intermediate layer is present, the surface layer inside the compound layer is provided between the intermediate layer and the compound layer. By providing the surface layer, the wear resistance can be further improved.

  The surface layer is preferably composed of TiAlN, TiAlCN, TiSiN, TiSiCN and TiCN. The layer thickness of the surface layer is preferably in the range of 0.1 μm to 5 μm. This is because if the thickness is less than 0.1 μm, the effect may not be sufficiently obtained. On the other hand, if the thickness exceeds 5 μm, the ratio of the intermediate layer in the entire film increases, and thus there is a possibility that the wear resistance and weldability of the entire film deteriorate.

  Furthermore, in the wear resistant coating of the present invention, an outermost surface layer may be further provided on the outermost surface of the coating from the viewpoint of improving wettability at low temperatures. The outermost surface layer may be composed of TiCN or CrN, or a compound layer and the surface layer may be alternately and repeatedly disposed. By doing in this way, the balance of abrasion resistance and welding resistance can be improved, and the toughness of an abrasion-resistant film can be improved.

  The wear-resistant coating of the present invention has a maximum hardness in a hardness test by a nanoindentation method performed by applying a controlled indentation load so that the indentation depth is 1/10 or less of the thickness of the coating. When the indentation depth is hmax and the indentation depth (indentation depth) after unloading is hf, (hmax−hf) / hmax may be a numerical value of 0.2 to 0.7. preferable. If it is less than 0.2, it is difficult to obtain desired wear resistance, and if it exceeds 0.7, the toughness is inferior, which is not preferable.

  In the wear resistant coating of the present invention, it is preferable that the hardness in the thickness direction of the coating by the nanoindenter is changed in the range of 20 GPa to 50 GPa. If it is less than 20 Gpa, there is a problem in wear resistance, and if it exceeds 50 Gpa, the toughness is deteriorated and the deficiency may be deteriorated with respect to impact.

  Here, the nanoindentation method is a kind of hardness test as described in detail in the document “Tribologist, Vol. 47, No. 3, (2002) p177-183”. The method for obtaining the hardness from the indented shape after indentation such as measurement and Vickers hardness measurement is different, and is a method for obtaining the hardness and Young's modulus from the relationship between the load and the depth when the indenter is pushed in.

  In the wear resistant coating of the present invention, the residual compressive stress is preferably in the range of −6 GPa to 0 GPa. If it is less than −6 Gpa, the peel resistance is lowered, which is not preferable. On the other hand, if it exceeds 0 Gpa, the film stress becomes tensile, and the film cracks and the crack propagates to the base material at the time of cutting, so that the deficiency is impaired or the curtain toughness is deteriorated. This internal compressive stress can be measured by a method using X-rays (a constant penetration depth method).

  The wear-resistant coating of the present invention can be used as a cutting tool or the like by coating the surface of a substrate. As the base material, an optimum material can be selected depending on the application, but when used for a cutting tool, WC-based cemented carbide, cermet, high-speed steel, ceramics (silicon carbide, silicon nitride, aluminum nitride, Aluminum oxide, etc.), cubic boron nitride sintered body, diamond sintered body, silicon nitride sintered body, or a base material made of aluminum oxide and titanium carbide is preferable. Among them, it is particularly preferable to use a WC-based cemented carbide, cermet, or cubic boron nitride sintered body as a base material. By using these base materials, the life as a cutting tool can be greatly extended.

  The method for forming the abrasion-resistant film of the present invention is not particularly limited, but is preferably a physical vapor deposition method, particularly an ion plating method in which a bias voltage is applied to the substrate, and more preferably a sputtering method, An unbalanced magnetron sputtering method is preferred. In particular, a method of applying a negative bias voltage in the unbalanced magnetron sputtering method is preferable. By these methods, it is possible to obtain adhesion and toughness which are characteristics required as a wear-resistant member without impairing the characteristics of the substrate. In particular, in the case of the unbalanced magnetron sputtering method, it is possible to form a wear-resistant film with few sharp protrusions by controlling the forming conditions and the target cleaning process during the formation.

  An example of an apparatus for producing the abrasion-resistant film of the present invention will be described with reference to FIG. FIG. 1 is a schematic view of a film forming apparatus that can be used in the present invention. In FIG. 1, a chamber 1 includes a substrate holder 4, arc evaporation sources 6 and 8, and an unbalanced sputter evaporation source 7. Arc power sources 9 and 11 and a sputter power source 10 are connected to the arc evaporation sources 6 and 8 and the sputter evaporation source 7, respectively.

  The chamber 1 is connected to a vacuum pump (not shown), and the pressure in the chamber 1 can be changed through an exhaust port 3 provided in the chamber 1. A base material 5 in the chamber 1 is held by a base material holder 4. The substrate holder 4 is electrically connected to the negative electrode of the DC power source 12 for substrate bias.

  A gas introduction port 2 for supplying gas to the chamber 1 is provided, and various gases can be introduced into the gas introduction port 2 via a mass flow controller (not shown). Examples of the gas include an inert gas such as argon, a reactive gas such as nitrogen gas, oxygen gas, hydrocarbon gas such as methane, acetylene, and benzene, carbon monoxide, carbon dioxide, oxygen nitride, and the like. .

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not intending to be limited to this.

(Example 1)
1. Production of surface-coated cutting tools

  First, an ISO P30 cemented carbide tool having an SDKN42 shape was prepared as a base material. Next, the surface of the base material was coated with the abrasion-resistant film of the present invention using the above-described film forming apparatus.

Specifically, first, a 50 atom% Ti-50 atom% Al target is installed in the evaporation source 6, a 65 atom% Al-35 atom% Cr target is installed in the evaporation source 7, and a Ti target is installed in the evaporation source 8. The base material 5 is held by the base material holder 4 and set so as to face the evaporation source 6, and the inside of the chamber 1 is depressurized by a vacuum pump, and the base material 5 is heated to a temperature of 550 ° C. by the heater 13. Then, vacuuming was performed until the pressure in the chamber 1 became 2.0 × 10 ⁻⁴ Pa.

  Next, Ar gas was introduced from the gas inlet 2 to maintain the pressure in the chamber at 6.0 Pa, the voltage of the substrate bias power supply 12 was set to −1000 V, and the surface of the substrate 5 was cleaned for 30 minutes. . Thereafter, Ar gas was exhausted.

  Next, a mixed gas of 100 sccm of argon and nitrogen was introduced into the chamber 1 through the gas inlet 2 while maintaining the voltage of the substrate bias power supply 12 at −1000 V. An arc current of 100 A was supplied from the arc power source 11 to discharge the arc evaporation source 8 to generate metal ions for 10 minutes. As a result, the metal ions cleaned the surface of the base material 5 to remove strong dirt and oxide film on the surface of the base material 5.

  Thereafter, similarly, while discharging the evaporation source 6 at 80 A, nitrogen gas is introduced from the gas inlet 2 so that the pressure in the chamber 1 becomes 4.0 Pa, and the voltage of the substrate bias power source 12 is set to −200 V, A TiAlN layer was formed on the surface of the substrate 5. This state was maintained until the TiAlN layer reached a predetermined thickness (2.5 μm). Thereby, a TiAlN film as an intermediate layer was formed.

When the formation of the intermediate layer was completed, the discharge of the arc evaporation source 6 was stopped in this state, and then 500 W of power was supplied to the sputter evaporation source 7 to generate a discharge. The bias voltage was −100V. A layer made of a compound having a composition of (Al _0.65 Cr _0.35 ) N having a thickness of 1.1 μm is formed on the surface of the base material 5 by vaporization of Al and Cr constituting the evaporation source 7 in the forward direction. Formed.

  Further, the evaporation source 7 is stopped, and then an arc current 80A is supplied to the arc evaporation source 8 to generate an arc discharge so that the base material faces the evaporation source 8 and is added to the nitrogen gas from the inlet 2 Then, the same amount of methane gas was introduced, the bias voltage was set to −100 V, and a 0.1 μm thick TiCN layer was obtained as the outermost surface layer.

  2. Characterization

  The following characteristics were measured for the surface-coated cutting tool thus obtained. First, the surface form of the surface-coated cutting tool was observed with a scanning electron microscope (SEM). At a magnification of 1000 times, the number of protrusions having a diameter of 1 μm or more and a height of 1 μm or more within the range of 100 μm × 100 μm on the surface was counted. It was 3.2 when the arbitrary 5 places were measured in the said 100 micrometer x 100 micrometer range, and the number of the protrusions obtained was averaged.

  The Ar content in the layer made of the compound in the wear-resistant coating of the obtained surface-coated cutting tool was measured using Rutherford backscattering measurement (RBS) method. As a result of RBS, the amount of Ar in the CrAlN compound layer was 0.02 atomic%.

  Moreover, the hardness test was done so that the maximum indentation depth might be set to 0.3 micrometer using the nano indentation method with respect to the abrasion-resistant film of the obtained surface coating cutting tool. Assuming that the maximum indentation depth is hmax and the indentation depth (indentation depth) after load removal is hf, (hmax−hf) / hmax was 0.5. The hardness was 35 GPa.

  Moreover, as a result of evaluating the crystal structure of the layer composed of the compound in the wear-resistant coating film by X-ray diffraction, it was a NaCl type crystal structure.

  Regarding these results, compositions, film thicknesses and amounts of Ar are shown in Tables 1 and 2, and tests by the nanoindentation method, residual stress, and average number of protrusions are shown in Table 3.

  (Examples 2 to 14)

By adjusting the composition ratio of each layer of the wear-resistant coating, the composition ratio of the target material installed in each evaporation source, and the type and flow rate ratio of the gas introduced at the time of layer formation, Examples 2 to 12 shown in Table 1 and A surface-coated cutting tool was produced in the same manner as in Example 1 except that the composition ratios of Examples 13 and 14 shown in Table 2 were used. In Example 14, layers 1 and 2 made of a compound were alternately laminated 15 times. The Ar content was adjusted by changing the Ar partial pressure and substrate temperature during formation of the compound layer, and the bias voltage during formation. The number of surface protrusions was adjusted by the film formation pressure and bias voltage at the time of forming the compound layer, and the condition and time of metal ion cleaning. The results are shown in Tables 1-3.

  (Comparative Examples 1-3)

  Except that the composition of the coating was changed, a cutting tool was prepared in the same manner as in Example 1 as Comparative Example 1, and when forming the compound, the substrate temperature was 950 ° C., and the Ar content was less than 0.007 atomic%. A cutting tool was prepared in the same manner as in Example 1 except that it was made Comparative Example 2, and the cutting tool was made in the same manner as in Example 1 except that the number of protrusions having a diameter of 1 μm or more and a height of 1 μm or more was 10 or more. The produced sample is referred to as Comparative Example 3, and the results for Comparative Examples 1 to 3 are shown in Tables 1 and 3.

  3. Cutting test

  About the cutting tool of the said Examples 1-14 and Comparative Examples 1-3, the cutting test was done on the processing conditions shown in Table 3, and flank wear width was evaluated. The smaller the flank wear width, the longer the life of the cutting tool. Therefore, from the results shown in Table 3, the surface-coated cutting tool of the present invention has a smaller wear and a longer life than the cutting tool of the comparative example. I understand that.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic diagram which shows an example of the apparatus used for film-forming of the abrasion-resistant film of this invention.

Explanation of symbols

  1 chamber, 2 gas inlet, 3 exhaust port, 4 substrate holder, 5 substrate, 6 arc evaporation source, 7 unbalanced sputter evaporation source, 8 arc evaporation source or unbalanced sputter evaporation source, 9 Arc power source, 10 Sputter power source, 11 Arc power source or Sputter power source, 12 Base material bias power source, 13 Base material heater.

Claims (12)

  It consists of a metal element selected from the group consisting of Cr, Al and Si and one or more elements of C, N or O, and further contains 0.001 atomic% or more and less than 5 atomic% of Ar atoms. A wear-resistant coating comprising one or more layers composed of a compound, wherein a protrusion having a diameter of 1 μm or more and a height of 1 μm or more is formed on the surface of the wear-resistant coating. A wear-resistant coating film characterized by being present in an average of less than 10 pieces within a range of 100 μm × 100 μm. Of composed layer from said compound, the composition of elements except for Ar _{atoms, (Cr 1-x-y} Al x Si y) (C u N 1-u-v O v) ( except, 0.2 ≦ x ≦ 0.75, 0 ≦ y ≦ 0.2, x + y ≦ 0.75, 0 ≦ u ≦ 0.5, 0 ≦ v ≦ 0.2, u + v ≦ 0.6), The wear-resistant coating film according to claim 1.   The wear-resistant film according to claim 1 or 2, wherein the crystal structure of the layer composed of the compound is a NaCl-type crystal structure.   The wear-resistant coating film according to claim 1 or 2, wherein the crystal structure of the layer composed of the compound includes a NaCl-type crystal structure and an amorphous structure.   5. The wear-resistant coating film according to claim 1, wherein the layer composed of the compound has a layer thickness of 0.1 μm or more and 10 μm or less per layer.   Hardness test by the nanoindentation method that is carried out by applying an indentation load controlled so that the indentation depth is 1/10 or less of the total layer thickness of the layer composed of the compound. The maximum indentation depth is hmax and the indentation depth after load unloading is hf, wherein (hmax−hf) / hmax is 0.2 or more and 0.7 or less. The abrasion-resistant film according to any one of 1 to 5.   Hardness test by the nanoindentation method that is carried out by applying an indentation load controlled so that the indentation depth is 1/10 or less of the total layer thickness of the layer composed of the compound. The wear-resistant coating film according to claim 1, wherein the hardness is 20 GPa or more and 50 GPa or less.   Residual compressive stress is -6 GPa or more and 0 GPa or less, The abrasion-resistant film in any one of Claims 1-7 characterized by the above-mentioned.   A surface-coated cutting tool, wherein the wear-resistant coating according to any one of claims 1 to 8 is coated on a surface of a substrate.   The base material is a WC base cemented carbide, cermet, high speed steel, ceramics, cubic boron nitride sintered body, diamond sintered body, silicon nitride sintered body, or a base material made of aluminum oxide and titanium carbide. The surface-coated cutting tool according to claim 9, wherein the surface-coated cutting tool is any one.   The surface-coated cutting tool according to claim 9 or 10, wherein the wear-resistant coating is formed on the surface of the base material using a physical vapor deposition method.   The surface-coated cutting tool according to claim 11, wherein the physical vapor deposition method is an unbalanced magnetron sputtering method, and the method includes a step of applying a negative bias voltage to the substrate. .

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