JP2011167792A - Surface coated cutting tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface coated cutting tool whose hard coating layer exerts excellent wear resistance under a high speed cutting condition of a heat resistant alloy such as an Ni-based alloy, a Co-based alloy. <P>SOLUTION: In the surface coated cutting tool in which a hard coating layer of an alternately laminated structure of multilayer regions alternately laminated with thin layers A with 1-50 nm layer thickness and thin layers B with 1-50 nm layer thickness and single layer regions constructed of a single layer with 100-500 nm layer thickness is formed on the surface of a base body of the tool by vapor deposition, the thin layer A is a layer [Ti<SB>1-X</SB>Si<SB>X</SB>] N (wherein X is 0.01-0.30 in terms of atomic ratio), the thin layer B is a layer [Ti<SB>1-Y</SB>V<SB>Y</SB>] N (wherein Y is 0.40-0.70 in terms of atomic ratio), and the single layer is constructed of a layer of a same kind as that of the thin layer A or the thin layer B. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention provides a surface-coated cutting tool that exhibits excellent wear resistance with a hard coating layer even when heat-resistant alloys such as Ni-base alloys and Co-base alloys are cut under high-speed cutting conditions with high heat generation. (Hereinafter referred to as a coated tool).

  In general, for coated tools, throwaway inserts that are detachably attached to the tip of the cutting tool for turning and planing of various steel and cast iron materials, drilling of the work material, etc. Drills, miniature drills, solid type end mills used for chamfering, grooving, shouldering, etc. of the work material, and the solid type A slow-away end mill tool that performs cutting work in the same manner as an end mill is known.

Further, as a specific coated tool, for example, as shown in Patent Document 1, a type A as a hard coating layer is formed on the surface of a tool base made of a tungsten carbide (hereinafter referred to as WC) -based cemented carbide. A hard coating layer composed of alternating primary partial layers of type B and secondary partial layers of type B, and further forming the primary partial layer of type A in an alternately laminated structure (for example, TiN-AlN, HfC-NbO). , ZrCN—TaN, VN—BN, Al 2 O 3 —TiCN, TiAlN—TiN, and a secondary partial layer of the above type B as a single layer (eg, TiN, TiC, SiC, TaCN) ) Is known (hereinafter referred to as a conventional coated tool), and this coated tool is known to have excellent welding resistance and wear resistance.
Moreover, as shown in Patent Documents 2 to 4, in a coated tool in which a hard coating layer having a multilayer structure is formed on the surface of a tool base made of a WC-base cemented carbide, as one layer constituting the multilayer structure It is also known to provide a composite nitride layer of Ti and Si (hereinafter referred to as (Ti, Si) N layer), and the (Ti, Si) N layer improves high-temperature hardness and oxidation resistance. It is also known.

  And the coating tool shown by the said patent documents 1-4 is an arc ion plating apparatus which has arrange | positioned the several cathode electrode (evaporation source) which has a component composition according to the kind of hard coating layer to carry out vapor deposition, for example, A tool base is inserted into the apparatus, the inside of the apparatus is set to a nitrogen gas reaction atmosphere, and in a heated state, arc discharge is sequentially generated between a plurality of cathode electrodes (evaporation sources) and anode electrodes, It is also known that the above-mentioned tool base is manufactured by forming a film under conditions where a bias voltage is applied, and vapor-depositing a hard coating layer having an alternately laminated structure or a multilayer structure on the surface of the tool base. It has been.

Japanese Patent No. 4185172 JP 2000-334606 A JP 2000-334607 A JP 2008-162009 A

  In recent years, the performance of cutting equipment has been remarkable. On the other hand, there is a strong demand for labor saving and energy saving and further cost reduction for cutting work. Although generalization of cutting tools for various work materials is also required, in the coated tools shown in Patent Documents 1 to 4, when this is used for cutting under normal conditions such as steel and cast iron, Although no particular problem occurs, for example, when used for high-speed cutting with high heat generation of heat-resistant alloys such as Ni-base alloys and Co-base alloys, the heat conductivity of the heat-resistant alloy that is the work material is low, Since the surface temperature of the cutting edge of the cutting tool is increased by the cutting heat, delamination of the hard coating layer constituting the alternately laminated structure or the multilayer structure occurs, and as a result, the wear resistance of the hard coating layer is not fully exhibited. , Use in a relatively short time The leads to life is the status quo.

  In view of the above, the present inventors, from the above-mentioned viewpoints, do not cause the occurrence of welding or delamination even when used for high-speed cutting with high heat generation of heat-resistant alloys such as Ni-base alloys and Co-base alloys. In order to develop a coated tool that exhibits excellent wear resistance without any hard coating layer, we have conducted intensive research.

In the alternate layering of the above-mentioned conventional coated tools, in the (Ti, Si) N layer constituting one layer of the multilayer, the Ti component has the effect of improving the high temperature toughness and the high temperature strength, and the Si component is In order to improve the oxidation resistance and suppress the decrease in the hardness of the layer due to oxidation, by providing the (Ti, Si) N layer as one of the alternate layers and multiple layers, the oxidation resistance under normal cutting conditions There is an improvement in wear resistance.
However, since the (Ti, Si) N layer is inferior in toughness and has insufficient lubricity, the cutting edge surface temperature becomes high in high-speed cutting of heat-resistant alloys such as Ni-base alloys and Co-base alloys. Therefore, abnormal damage such as chipping and defects is likely to occur, and when the (Ti, Si) N layer constitutes one layer of an alternately laminated structure, the layer thickness increases in the hard coating layer. The internal stress (strain) accumulates more and more, but when this internal stress (strain) is released by high heat at the time of cutting, peeling between the layers constituting the alternate stack is likely to occur. There was a point.

  Therefore, the present inventors have examined the layer material constituting the alternate laminated structure in more detail, and as in the past, the hard coating layer is not constituted as a regular alternating laminated structure, but the hard coating layer is formed. , (Ti, Si) N layers, and (Ti, V) N layers or (Ti, Si) N layers or (Ti, Si) N layers, , V) When composed of a single layer region consisting of any one of the N layers and a hard coating layer as an alternate laminated structure of the multilayer region and the single layer region, the following knowledge is obtained. I got it.

That is, in the multilayer region of the hard coating layer in which the thin layer A composed of (Ti, Si) N layers and the thin layer B composed of (Ti, V) N layers are alternately laminated, the grains of the respective layers In addition to improving the film strength, it has excellent oxidation resistance, high hardness, high toughness, and high lubricity, and the alternate laminated structure of thin layer A and thin layer B By preventing propagation and progress, chipping resistance, chipping resistance and wear resistance are improved.
In addition to this, in the hard coating layer, a single layer region composed of a single layer of (Ti, Al) N layer or (Ti, V) N layer is formed. Since the internal stress (strain) accumulated in the region is relieved by the presence of the single layer region, the hard coating layer as a whole does not generate large internal stress (strain), and as a result, It has been found that the occurrence of delamination is suppressed in high-speed cutting of heat-resistant alloys such as Ni-base alloys and Co-base alloys.

This invention has been made based on the above findings,
"In a surface-coated cutting tool in which a hard coating layer is deposited on the surface of a tool substrate,
The hard coating layer includes a multilayer region in which thin layers A having a thickness of 1 to 50 nm and thin layers B having a thickness of 1 to 50 nm are alternately stacked, and a single layer having a thickness of 100 to 500 nm. And the hard coating layer is configured as an alternately laminated structure of the multilayer region and the single layer region,
(A) The thin layer A is
_{Formula: [Ti 1-X Si X} ] N
X is composed of a composite nitride layer of Ti and Si that satisfies 0.01 to 0.30 (however, atomic ratio),
(B) The thin layer B is
Composition formula: [Ti _1-Y V _Y ] N
Y is composed of a composite nitride layer of Ti and V that satisfies 0.40 to 0.70 (however, the atomic ratio),
(C) The single layer is
_{Formula: [Ti 1-X Si X} ] N
X is a composite nitride layer of Ti and Si that satisfies 0.01 to 0.30 (however, the atomic ratio), or
Composition formula: [Ti _1-Y V _Y ] N
Y is composed of any one of Ti and V composite nitride layers satisfying 0.40 to 0.70 (however, atomic ratio).
A surface-coated cutting tool characterized by that. "
It has the characteristics.

  The hard coating layer of the coated tool of this invention is demonstrated below.

Thin layer A ((Ti, Si) N layer) in the multilayer region:
The thin layer A composed of the (Ti, Si) N layers, which are alternately stacked with the thin layers B ((Ti, Al) N layers) to form the multilayer region of the hard coating layer of the present invention, is excellent due to the Si component. Because of its high oxidation resistance, excellent high hardness is maintained even at high temperatures in high-speed cutting of heat-resistant alloys such as Ni-base alloys and Co-base alloys.
A thin layer A composed of a (Ti, Si) N layer,
_{Formula: [Ti 1-X Si X} ] N
X is composed of a composite nitride layer of Ti and Si satisfying 0.01 to 0.30 (however, atomic ratio), but the value of X indicating the content ratio of Si (however, atomic ratio) However, if it is less than 0.01, the high-temperature hardness of the thin layer A will be insufficient. On the other hand, if the value of X exceeds 0.30, the high-temperature toughness and high-temperature strength of the thin layer A will decrease. Therefore, the value of X was set to 0.01 to 0.30 (however, the atomic ratio).

Thin layer B ((Ti, Al) N layer) in the multilayer region:
The thin layer B composed of the (Ti, Al) N layer, which is alternately laminated with the thin layer A ((Ti, Si) N layer) to form the multilayer region of the hard coating layer of the present invention, has improved toughness and lubricity. Since it is excellent, by alternately laminating with the thin layer A, so to speak, it complements the relatively lacking characteristics of the thin layer A, and at the same time, increases the strength of the multilayer region and further improves the interlayer adhesion. .
A thin layer B composed of a (Ti, V) N layer,
Composition formula: [Ti _1-Y V _Y ] N
Y is a composite nitride layer of Ti and V that satisfies 0.40 to 0.70 (however, atomic ratio), and the value of Y (however, atomic ratio) indicating the content ratio of V is If the value is less than 0.40, the toughness and lubricity of the thin layer B become insufficient. On the other hand, if the value of Y exceeds 0.70, the high-temperature hardness of the thin layer B decreases. Was defined as 0.40 to 0.70 (however, atomic ratio).

Layer thickness of thin layer A and thin layer B:
In the multi-layer region formed by alternately laminating the thin layer A and the thin layer B, each layer is adjacent to each other to form a layer having a different composition, thereby preventing the growth of particle growth of each layer. As a result, the particles are made finer, the film strength is improved, and crack propagation and progress are prevented by this laminated structure, so that the chipping resistance and chipping resistance are improved. When each layer thickness of the layer B is less than 1 nm, it is difficult to clearly form each thin layer as having a predetermined composition, and the above-described excellent characteristics possessed by each thin layer cannot be exhibited. On the other hand, if the thickness of each layer exceeds 50 nm, the film strength is reduced due to the coarsening of the particles, so that the chipping resistance and chipping resistance are reduced. 1 to 50 nm.
In addition, the multi-layer region in which the thin layer A and the thin layer B are alternately laminated, when the region thickness is less than 0.01 μm, sufficiently exhibits the high hardness provided by the thin layer A to improve the wear resistance. On the other hand, if the thickness of the region exceeds 0.5 μm, chipping and defects are likely to occur. Therefore, the region thickness of the multilayer region in which the thin layers A and B are alternately laminated is 0. It is desirable that it is 01-0.5 micrometer.

Single layer area:
The single layer region is composed of a single layer having the same component composition as that of the thin layer A, or the component / composition of the single layer region is composed of a single layer having the same component composition as that of the thin layer B. The single layer region does not have to be formed of a single layer of the same material type as the thin layer A or a single layer of the same material type as the thin layer B. For example, a single layer region thin layer on the tool base side It is comprised by the single layer of the same material type as A, and the single layer area | region may be comprised by the single layer of the same material type as the thin layer A in the surface layer side of a hard coating layer.
That is, the single-layer region formed along the layer thickness direction may be the same material type as the thin layer A or the same material type as the thin layer B and may be configured as a single layer.
This single layer region has a predetermined effect according to the material type (for example, if it is the same material type as the thin layer A, it has high hardness and oxidation resistance, and the same material type as the thin layer B). In addition to such operational effects, the presence of a single layer region increases the internal stress (strain) accumulated in the multilayer region, and this single layer region has high toughness and high lubricity. It has a great technical significance in terms of mitigating the impact, and also has the effect of mitigating the impact force applied to the hard coating layer during the cutting process in this single layer region.
Therefore, no large internal stress (strain) is formed in the hard coating layer as a whole, and as a result, even in high-speed cutting with high heat generation of heat-resistant alloys such as Ni-base alloys and Co-base alloys. The occurrence of delamination is suppressed.
However, when the thickness of the single-layer region is less than 100 nm, the internal stress relaxation action and impact force relaxation action cannot be sufficiently expected. On the other hand, when the thickness exceeds 500 nm, the hard coating layer as a whole is resistant to oxidation. Therefore, the region thickness of the single layer region is determined to be 100 to 500 nm.

Hard coating layer thickness:
The hard coating layer configured as an alternate lamination of the multilayer region and the single layer region can sufficiently exhibit excellent cutting performance over a long period of use when the overall layer thickness is less than 0.3 μm. On the other hand, if the total layer thickness exceeds 5 μm, chipping, defects and the like are likely to occur. Therefore, the total layer thickness of the hard coating layer is preferably 0.3 to 5 μm.

  In the surface-coated cutting tool of the present invention, the hard coating layer is configured as an alternately laminated structure of a multilayer region where thin layers A and thin layers B are alternately laminated and a single layer region consisting of a single layer. In the multilayer region, the film strength of each thin layer is improved, the thin layer A has excellent oxidation resistance and high hardness, the thin layer B has high toughness and high lubricity, and cracks Suppressing the propagation and progress of the material improves chipping resistance, chipping resistance, and wear resistance, and in addition to this, the presence of a single layer region makes it particularly easy to form and accumulate in multiple layer regions. Since the internal stress (strain) is alleviated, delamination caused by this can be prevented, and the mechanical impact applied during the cutting process can also be alleviated. High speed cutting with high heat generation of heat-resistant alloys such as When used in the processing is to exert excellent cutting performance over a long period of time.

The arc ion plating apparatus used for forming a hard coating layer is shown, (a) is a schematic plan view, and (b) is a schematic front view. It is a cross-sectional schematic diagram of the hard coating layer of the coating tool of this invention.

  Next, the coated tool of the present invention will be specifically described with reference to examples.

As raw material powders, WC powder, TaC powder, NbC powder, Cr ₃ C ₂ powder and Co powder all having an average particle diameter of 1 to 3 μm are prepared, and these raw material powders are blended in the composition shown in Table 1. The mixture is wet mixed in a ball mill for 72 hours, dried, and then pressed into a green compact at a pressure of 100 MPa. The green compact is sintered in a 6 Pa vacuum at a temperature of 1400 ° C. for 1 hour. After the sintering, honing of R: 0.02 was applied to the cutting edge portion to form tool bases A-1 to A-5 made of a WC-based cemented carbide having a chip shape of ISO standard / CNMG120408.

(A) Next, each of the tool bases A-1 to A-5 is ultrasonically cleaned in acetone and dried, and the center on the rotary table in the arc ion plating apparatus shown in FIG. Attached along the outer periphery at a predetermined distance in the radial direction from the shaft, each cathode electrode (evaporation source) has a component composition corresponding to the target composition shown in Table 2 (Ti, Si) ) N-layer forming Ti-Si alloy, (Ti, V) N-layer forming Ti- having a component composition corresponding to the target composition shown in Table 2, respectively, as the opposite cathode electrode (evaporation source) A V alloy is disposed across the rotary table.
A cathode electrode (evaporation source) made of a Ti—Si alloy is used for vapor deposition formation of a thin layer A and a single layer region, and a cathode electrode (evaporation source) made of a Ti—V alloy is made of a thin layer B and a single layer region. Used for vapor deposition.
(B) First, the inside of the apparatus is evacuated and kept at a vacuum of 0.5 Pa or less, and the inside of the apparatus is heated to 500 ° C. with a heater, and then the tool substrate that rotates while rotating on the rotary table is −1000 V A DC bias voltage is applied, for example, a current of 100 A is passed between a cathode electrode and an anode electrode of a Ti—Si alloy (or Ti—V alloy) to generate an arc discharge, and the tool base surface is bombarded. .
(C) Next, while introducing nitrogen gas as a reaction gas into the apparatus to make a reaction atmosphere of 2 Pa, while rotating on the rotary table at a speed of 6 to 48 rpm, at the same time, the rotation center axis of the rotary table A DC bias voltage of −80 V is applied to a tool base that rotates (revolves) at a speed of 1 to 8 rpm around it, for example, a current of 120 A flows between a Ti—V alloy cathode electrode and an anode electrode to cause arc discharge. At the same time, a current of 120 A is passed between the Ti—Si alloy cathode electrode and the anode electrode, which are arranged opposite to the Ti—V alloy cathode electrode with the rotary table interposed therebetween, and arc discharge is generated. A thin layer B is deposited on the tool base located near the V alloy cathode electrode, and a thin layer A is deposited on the tool base located near the Ti-Si alloy cathode electrode. By rotating the rotary table, the thin layer A is deposited on the tool base on which the thin layer B is deposited, and the thin layer B is deposited on the tool base on which the thin layer A is deposited. Then, the thin layer A and the thin layer B are alternately deposited repeatedly, so that the thin layer A and the thin layer B having the target composition and the target layer thickness shown in Tables 2 and 3 are alternately formed on the surface of the tool substrate. A multilayer region laminated on the substrate is formed.
(D) Next, nitrogen gas is introduced as a reaction gas into the apparatus, and while rotating at a speed of 6 to 48 rpm on the rotary table while maintaining a reaction atmosphere of 2 Pa, 1 around the rotation center axis of the rotary table. A DC bias voltage of −150 V is applied to a tool base on which a multilayer region that rotates (revolves) at a speed of ˜8 rpm is applied, and a Ti—V alloy cathode electrode (or a Ti—Si alloy cathode electrode) and an anode electrode During this period, an electric current of 100 A is applied to generate an arc discharge, so that a single layer region having a target composition and a target layer thickness shown in Tables 2 and 3 is deposited on the surface of the tool substrate.
(E) Next, by repeating the above (c) and (d) alternately until the target total thickness of the hard coating layer is reached,
The present invention coated tips 1 to 10 as the present invention coated tool of the throwaway tip shape defined in ISO / CNMG120408, which has a hard coating layer composed of an alternately laminated structure of a multilayer region and a single layer region shown in FIG. Each was manufactured.

For the purpose of comparison, these tool bases A-1 to A-5 were ultrasonically cleaned in acetone and dried, and then charged into the arc ion plating apparatus shown in FIG. As a source), a Ti-V alloy and a Ti-Si alloy each having a component composition corresponding to the target composition shown in Table 4 are mounted,
First, while evacuating the interior of the apparatus and maintaining the vacuum at 0.5 Pa or less, the interior of the apparatus was heated to 500 ° C. with a heater, a DC bias voltage of −1000 V was applied to the tool base, and Ti of the cathode electrode -Si alloy (or Ti-V alloy) A current of 100 A is passed between the cathode electrode and the anode electrode to generate an arc discharge, whereby the tool base surface is bombarded,
Next, nitrogen gas is introduced into the apparatus as a reaction gas to make a reaction atmosphere of 2 Pa, and the bias voltage applied to the tool base is lowered to −100 V, for example, a cathode electrode and an anode electrode of the Ti—V alloy, Arc discharge is generated during the process, and the (Ti, V) N layer having the target composition and target layer thickness shown in Table 4 is formed on the surface of the tool base by vapor deposition.
Next, an arc discharge is generated between the cathode electrode and the anode electrode of the Ti—Si alloy, and the (Ti, Si) N layer having the target composition and target layer thickness shown in Table 4 is formed on the surface of the tool base. Vapor deposition,
By alternately repeating the deposition formation of the above (Ti, V) N layer and (Ti, Si) N layer,
Comparative coated tips 1 to 10 as a comparative coated tool in the form of a throwaway tip defined in ISO · CNMG120408, each having a hard coating layer composed of alternately laminated target compositions and target layer thicknesses shown in Table 4, were produced.

Next, in the state where each of the above various coated chips is screwed to the tip of the tool steel tool with a fixing jig, the present coated chips 1 to 10 and the comparative coated chips 1 to 10 are as follows.
Work Material: Ni-19% Cr-18.5% Fe-5.2% Cd-5% Ta-3% Mo-0.9% Ti-0.5% Al-0.3% by mass% Four longitudinally-grooved round bars at equal intervals in the length direction of a Ni-based alloy having a composition of Si-0.2% Mn-0.05% Cu-0.04% C,
Cutting speed: 100 m / min. ,
Cutting depth: 1.5 mm,
Feed: 0.2 mm / rev. ,
Cutting time: 5 minutes,
A dry high-speed intermittent cutting test of a Ni-based alloy under the above conditions (cutting condition A) (normal cutting speed is 30 m / min.),
Work material: Equal intervals in the length direction of Co-based alloy having a composition of Co-23% Cr-6% Mo-2% Ni-1% Fe-0.6% Si-0.4% C in mass% 4 fluted round bars,
Cutting speed: 80 m / min. ,
Cutting depth: 1.5 mm,
Feed: 0.15 mm / rev. ,
Cutting time: 5 minutes,
A dry high-speed intermittent cutting test of a Co-based alloy under the following conditions (cutting condition B) (normal cutting speed is 25 m / min.),
In each cutting test, the flank wear width of the cutting edge was measured. The measurement results are shown in Table 5.

As raw material powders, WC powder having an average particle size of 0.8 μm, 2.3 μm Cr ₃ C ₂ powder, 1.5 μm VC powder, and 1.8 μm Co powder were prepared. 6 was added to the composition shown in FIG. 6 and added with wax, mixed in a ball mill for 24 hours in acetone, dried under reduced pressure, and then press-molded into various compacts of a predetermined shape at a pressure of 100 MPa. The body is heated to a predetermined temperature in the range of 1370 to 1470 ° C. at a heating rate of 7 ° C./min in a vacuum atmosphere of 6 Pa, held at this temperature for 1 hour, and then sintered under furnace cooling conditions. Then, a round tool sintered body for forming a tool base is formed, and further, a diameter of the cutting edge portion × length is 10 mm × 22 mm and a twist angle is 45 degrees by grinding from the round bar sintered body. Made of WC-based cemented carbide with a 4-flute square shape Tool substrate (end mill) C-1~C-4 were prepared, respectively.

  Next, the surfaces of these tool bases (end mills) C-1 to C-4 were ultrasonically cleaned in acetone and dried, and then charged into the arc ion plating apparatus shown in FIG. A multi-layer region in which thin layers A and B are alternately laminated, and a single-layer region having the target composition and target layer thickness shown in Table 7 along the layer thickness direction under the same conditions as in Example 1. The coated end mills 1 to 8 of the present invention as the coated tool of the present invention were produced by vapor-depositing a hard coating layer having an alternately laminated structure.

  For the purpose of comparison, the surfaces of the tool bases (end mills) C-1 to C-4 are ultrasonically cleaned in acetone and dried, and then mounted on the arc ion plating apparatus shown in FIG. Then, under the same conditions as in Example 1, the (Ti, V) N layer having the target composition and target layer thickness shown in Table 8 is formed on the surface of the tool base (end mill) C-1 to C-4 ( Comparative coating end mills 1 to 8 as comparative coating tools were manufactured by vapor-depositing a hard coating layer composed of alternating layers of Ti, Si) N layers.

Next, for the present invention coated end mills 1-8 and comparative coated end mills 1-8,
Work Material-Plane Dimensions: 100mm x 250mm, Thickness: 50mm, Mass%, Ni-19% Cr-14% Co-4.5% Mo-2.5% Ti-2% Fe-1.2 Ni-base alloy plate material having a composition of% Al-0.7% Mn-0.4% Si,
Cutting speed: 40 m / min. ,
Groove depth (cut): 2.5 mm,
Table feed: 100 mm / min,
Ni-base alloy dry high-speed grooving test under the conditions (normal cutting speed and groove depth are 25 m / min. And 1.2 mm, respectively),
The cutting groove length was measured until the flank wear width of the outer peripheral edge of the cutting edge reached 0.1 mm, which is a guide for the service life. The measurement results are shown in Tables 7 and 8, respectively.

  Using the round bar sintered body manufactured in Example 2 above, from this round bar sintered body, the diameter x length of the groove forming portion is 8 mm x 48 mm and the helix angle is 30 degrees by grinding. WC base cemented carbide tool bases (drills) D-1 to D-4 each having a two-blade shape were manufactured.

  Next, the cutting edges of these tool bases (drills) D-1 to D-4 are subjected to honing, ultrasonically cleaned in acetone, and dried to the arc ion plating apparatus shown in FIG. A multilayer region in which thin layers A and thin layers B are alternately laminated with the target composition and target layer thickness shown in Table 9 along the layer thickness direction under the same conditions as in Example 1 above. And this invention covering drill 1-8 as this invention covering tool was manufactured by carrying out vapor deposition formation of the upper layer which consists of an alternate lamination structure with a single layer field, respectively.

  For the purpose of comparison, the surfaces of the above-mentioned tool bases (drills) D-1 to D-4 are subjected to honing, ultrasonically cleaned in acetone and dried, and the arc ions shown in FIG. In the plating apparatus, under the same conditions as in Example 1, the target compositions and target layer thicknesses (Ti, V) shown in Table 10 are formed on the surfaces of the tool bases (drills) D-1 to D-4. Comparative coating drills 1 to 8 as comparative coating tools were manufactured by vapor-depositing a hard coating layer having an alternately laminated structure of N layers and (Ti, Si) N layers.

Next, for the present invention coated drills 1-8 and comparative coated drills 1-8,
Work Material—Plane Size: 100 mm × 250 mm, Thickness: 50 mm, Mass%, Ni-19% Cr-18.5% Fe-5.2% Cd-5% Ta-3% Mo-0.9 Ni-based alloy plate having a composition of% Ti-0.5% Al-0.3% Si-0.2% Mn-0.05% Cu-0.04% C,
Cutting speed: 50 m / min. ,
Feed: 0.25 mm / rev,
Hole depth: 20 mm,
Wet high-speed drilling test of Ni-based alloy under the following conditions (normal cutting speed and feed are 25 m / min. And 0.12 mm / rev, respectively),
(Using water-soluble cutting oil), and the number of drilling operations was measured until the flank wear width of the cutting edge surface reached 0.3 mm. The measurement results are shown in Tables 9 and 10, respectively.

  As a result of the present invention, the coated chips 1 to 10, the coated end mills 1 to 8 and the coated drills 1 to 8 of the present invention coated tip 1-8 and the laminated layers A and B are alternately laminated. (Ti, V) N that constitutes the alternate lamination of the thin layer A and the thin layer B of the layer region and the single layer region, and the comparison coating tip 1 to 10, the comparison coating end mill 1 to 8, and the comparison coating drill 1 to 8 When the compositions of the layer and the (Ti, Si) N layer were measured by energy dispersive X-ray analysis using a transmission electron microscope, they showed substantially the same composition as the target composition.

  Moreover, when the average layer thickness of said hard coating layer was cross-sectional measured using the scanning electron microscope, all showed the average value (average value of five places) substantially the same as target layer thickness.

From the results shown in Tables 5 and 7 to 10, the coated tool of the present invention has a hard coating layer in which a multi-layer region in which thin layers A and thin layers B are alternately laminated, and a single-layer region composed of a single layer. The multi-layered area improves chipping resistance, chipping resistance, and abrasion resistance, and the presence of the single-layered area prevents delamination and mechanically. Since the impact is mitigated, excellent cutting performance over a long period of time (especially chipping resistance and chipping resistance) when used in high-speed cutting with high heat generation of heat-resistant alloys such as Ni-base alloys and Co-base alloys , Exfoliation resistance and wear resistance).
On the other hand, in the comparative coating tool in which the hard coating layer is configured only by the alternate lamination of the (Ti, V) N layer and the (Ti, Si) N layer and does not have a single layer region, the Ni-based alloy, In high-speed cutting of heat-resistant alloys such as Co-based alloys, it is clear that the service life is reached in a relatively short time due to chipping, chipping, peeling, etc. due to insufficient lubricity and delamination resistance. is there.

  As described above, the coated tool of the present invention can be used for high-speed cutting of heat-resistant alloys such as Ni-base alloys and Co-base alloys with high heat generation as well as cutting of general steel and ordinary cast iron. Since it shows excellent cutting performance over a long period of time, it can satisfactorily cope with the FA of the cutting apparatus, labor saving and energy saving of cutting, and cost reduction.

Claims (1)

In a surface-coated cutting tool in which a hard coating layer is vapor-deposited on the surface of a tool substrate,
The hard coating layer includes a multilayer region in which thin layers A having a thickness of 1 to 50 nm and thin layers B having a thickness of 1 to 50 nm are alternately stacked, and a single layer having a thickness of 100 to 500 nm. And the hard coating layer is configured as an alternately laminated structure of the multilayer region and the single layer region,
(A) The thin layer A is
_{Formula: [Ti 1-X Si X} ] N
X is composed of a composite nitride layer of Ti and Si that satisfies 0.01 to 0.30 (however, atomic ratio),
(B) The thin layer B is
Composition formula: [Ti _1-Y V _Y ] N
Y is composed of a composite nitride layer of Ti and V that satisfies 0.40 to 0.70 (however, the atomic ratio),
(C) The single layer is
_{Formula: [Ti 1-X Si X} ] N
X is a composite nitride layer of Ti and Si that satisfies 0.01 to 0.30 (however, the atomic ratio), or
Composition formula: [Ti _1-Y V _Y ] N
Y is composed of any one of Ti and V composite nitride layers satisfying 0.40 to 0.70 (however, atomic ratio).
A surface-coated cutting tool characterized by that.

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