JP2008173756A - Surface-coated cutting tool having hard coating layer exhibiting excellent chipping resistance and excellent wear resistance in high-speed heavy cutting of heat resistant alloy - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface-coated cutting tool having a hard coating layer exhibiting excellent chipping resistance and excellent wear resistance in high-speed heavy cutting of a heat resistant alloy. <P>SOLUTION: The surface-coated cutting tool has a tool substrate made of a tungsten carbide-based cemented carbide or a titanium carbonitride-based cermet, and the hard coating layer applied to a surface of the tool substrate. The hard coating layer comprises a composite nitride layer composed of Cr, Al, and Si, vapor-deposited by arc ion plating, as a lower layer, and a composite nitride layer composed of Cr, Al, Si, Mo, and S, simultaneously vapor-deposited by arc ion plating and sputtering, as an upper layer. The upper layer is formed of a composition variable layer comprising (Al, Cr, Si, Mo, S)N having a mean layer thickness of 1 to 8 μm, in which a maximum point of Al-Cr-Si content and a maximum point of Mo-S content exist alternately repeatedly along a layer thickness direction at intervals of 0.03 to 0.1 μm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  This invention is hard even when cutting heat-resistant alloys such as Ti-base alloys, Ni-base alloys, and Co-base alloys under high-speed heavy cutting conditions that involve high heat generation and a heavy load on the cutting blade. The present invention relates to a surface-coated cutting tool (hereinafter referred to as a coated tool) that exhibits excellent chipping resistance and wear resistance.

  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 and miniature drills, and solid type end mills used for chamfering, grooving, shouldering, etc. of the work material, etc. A slow-away end mill tool that performs cutting work in the same manner as an end mill is known.

As one of the coated tools, the surface of a tool base composed of a tungsten carbide (hereinafter referred to as WC) -based cemented carbide or titanium carbonitride (hereinafter referred to as TiCN) -based cermet is coated with Al as a hard coating layer. Coated tools formed by physical vapor deposition of a nitride layer of Cr and Si [hereinafter referred to as (Al, Cr, Si) N] are known, and the hard coated layer of the coated tool has excellent high-temperature hardness. In addition, it has heat resistance and high temperature strength, and is known to exhibit excellent cutting performance when used for cutting various general steels and ordinary cast irons under normal conditions.
JP 2004-106183 A

  In recent years, the use of FA for cutting devices has been remarkable. On the other hand, there has been a strong demand for labor saving and energy saving and further cost reduction for cutting processing, and along with this, cutting processing tends to be further accelerated. In the case of a coated tool, there is no problem when it is used for cutting under normal conditions, but this is accompanied by a particularly high heat generation of a heat-resistant alloy such as a Ti-base alloy, Ni-base alloy, Co-base alloy and the like, and a cutting blade. When used for high-speed heavy cutting that requires a large load, chipping cannot be suppressed due to insufficient lubricity of the hard coating layer, welding, etc., and the progress of wear is also promoted. At present, the service life is reached in a short time.

In view of the above, the present inventors have developed the above-described coated tool that exhibits excellent chipping resistance and wear resistance with a hard coating layer particularly in high-speed heavy cutting of a heat-resistant alloy. As a result of conducting research focusing on conventional coated tools,
(B) For example, an (Al, Cr, Si) N deposition arc ion plating (AIP) apparatus and a Mo-S structure shown in FIG. 1 (a) are schematic plan views and FIG. Using a vapor deposition apparatus provided with a magnetron sputtering (SP) apparatus for vapor deposition, a rotary table for mounting a tool substrate (for example, a carbide substrate) is provided at the center of the apparatus, and a predetermined composition is formed on one side of the rotary table. Al-Cr-Si of an alloy cathode (evaporation source) with a (Al, Cr, Si) N deposition arc ion plating apparatus, on the other side, MoS having a MoS ₂ target (evaporation source) A magnetron sputtering apparatus for vapor deposition is arranged opposite to each other, and a plurality of tool bases are mounted in a ring shape on the rotary table for mounting the tool base at a predetermined distance from the central axis in the radial direction. In this state, the atmosphere inside the apparatus is changed to a nitrogen atmosphere, the rotary table is rotated, and the tool base itself is rotated for the purpose of uniformizing the thickness of the hard coating layer to be formed. Arc discharge is generated between the cathode electrode (evaporation source) and the anode electrode made of an Al—Cr—Si alloy of an arc ion plating apparatus for Al, Cr, Si) N deposition, and a predetermined layer thickness is formed on the surface of the tool base. A lower layer composed of a nitride layer of uniform Al, Cr, and Si (hereinafter referred to as an (Al, Cr, Si) N layer) is formed by evaporation, and then (Al, Cr, Si) N evaporation arc ions are formed. While generating arc discharge between the cathode electrode (evaporation source) and the anode electrode made of an Al—Cr—Si alloy of the plating apparatus, at the same time, the Mo-S deposition mug disposed oppositely. When sputtered MoS ₂ target (evaporation source) a pulse voltage is applied to the MoS ₂ Tron sputtering apparatus, by arc ion plating and sputtering, in the (Al, Cr, Si) consisting of N layer lower layer surface, and Al An upper layer composed of a nitride layer of Cr, Si, Mo and S (hereinafter referred to as (Al, Cr, Si, Mo, S) N layer) is formed by vapor deposition, and the upper layer is formed on a turntable. In the position where the arranged tool base is closest to the cathode electrode (evaporation source) of the Al-Cr-Si alloy on one side, the content ratio of Al, Cr, Si in the deposited layer is relatively maximum. is to, Mo, area proportion of S is minimized (hereinafter, Al-Cr-Si of up containing points) is formed, also, the tool base body, the other side of the MoS ₂ target (evaporation The region where the content ratio of Mo and S in the vapor deposition layer is relatively maximum and the content ratio of Al, Cr, Si is minimum (hereinafter referred to as the highest Mo-S content) And the highest Al-Cr-Si content point and the highest Mo-S content point according to the rotational speed of the rotary table along the layer thickness direction in the upper layer by the rotation of the rotary table. Appear alternately and repeatedly at a predetermined interval, from the Al-Cr-Si highest content point to the Mo-S highest content point, from the Mo-S highest content point to the Al-Cr-Si highest content point, Al, Cr, A vapor deposition layer having a component concentration distribution structure (hereinafter referred to as composition change (Al, Cr, Si, Mo, S) N layer) in which the contents of Si, Mo, and S continuously change is formed.

(B) In the upper layer of the hard coating layer composed of the composition change (Al, Cr, Si, Mo, S) N layer, the Al component improves high-temperature hardness, heat resistance and oxidation resistance, and the Cr component is The high temperature strength is improved, the Si component further improves the heat resistance, and the Mo component and S component are mostly in the form of MoS _{2 in} the upper layer, improving the lubricity with the work piece chips. Hard coating layer comprising the above-mentioned composition change (Al, Cr, Si, Mo, S) N layer at the Al-Cr-Si highest content point, which has an action to enhance and therefore has a relatively high Al, Cr, Si content ratio It has excellent high-temperature hardness, heat resistance, oxidation resistance, and high-temperature strength, but on the other hand, it does not have sufficient lubricity with the work piece swarf. The above composition change (A l, Cr, Si, Mo, S) In order to compensate for the lack of lubricity at the Al-Cr-Si highest content point of the N layer, the Mo-S highest content point with excellent lubricity is alternately arranged in the thickness direction. By interposing, the entire hard coating layer composed of the above-mentioned composition change (Al, Cr, Si, Mo, S) N layer has excellent high temperature hardness, heat resistance, oxidation resistance, high temperature strength and lubricity. As a result, excellent chipping resistance and wear resistance are exhibited without causing welding, uneven wear, etc. even when heavy cutting of a heat resistant alloy is performed under high speed conditions.
The research results shown in (a) and (b) above were obtained.

This invention was made based on the above research results,
“Turn table of vapor deposition apparatus in which a tungsten carbide based cemented carbide or titanium carbonitride based cermet is provided with an Al—Cr—Si alloy as a cathode electrode on one side and a MoS ₂ target on the other side The upper layer is placed on the surface of the tool base by arc ion plating on the Al—Cr—Si alloy cathode electrode side and sputtering on the MoS ₂ target side while the tool base is rotated on a rotary table. In surface-coated cutting tools in which a hard coating layer consisting of an upper layer is formed by vapor deposition,
The lower layer has an average layer thickness of 1 to 3 μm deposited by arc ion plating, and the content ratios (however, the atomic ratio) of the Al component, Cr component, and Si component are α, β, respectively. Al and Cr satisfying α + β + γ = 1 when α is 0.30 to 0.65, β is 0.30 to 0.65, γ is 0.01 to 0.10, and And Si composite nitride layer,
The upper layer is a composite nitride layer of Al, Cr, Si, Mo, and S having an average layer thickness of 1 to 8 μm formed by simultaneous vapor deposition of the arc ion plating and the sputtering, The upper layer is
(A) Along the layer thickness direction of the upper layer, the Al—Cr—Si highest content point formed in the vicinity of the Al—Cr—Si alloy cathode electrode and the Mo—S highest content formed in the vicinity of the MoS ₂ target And dots are alternately present at intervals of 0.03 to 0.1 μm,
(B) From the highest Al-Cr-Si content point to the highest Mo-S content point, from the highest Mo-S content point to the highest Al-Cr-Si content point, Al, Cr, Si, Mo, S Have a component concentration distribution structure in which the content ratio of each continuously changes,
(C) Al component, Cr component, Si component, Mo component and S component at the highest Al-Cr-Si content point formed in the vicinity of the Al-Cr-Si alloy cathode electrode, the content ratio (however, atom Ratio) is represented by X, Y, Z, Q, and R, respectively, X is 0.40 to 0.60, Y is 0.30 to 0.50, Z is 0.05 to 0.10, Q is 0.01 to 0.10, R is 0.01 to 0.10, and X + Y + Z + Q + R = 1 is satisfied,
(D) The Al component, Cr component, Si component, Mo component and S component at the Mo-S highest content point formed in the vicinity of the MoS ₂ target have their content ratios (however, the atomic ratio) set to X, When represented by Y, Z, Q, and R, X is 0.05 to 0.20, Y is 0.05 to 0.20, Z is 0.001 to 0.03, and Q is 0.25 to 0. .40, R is 0.40 to 0.55, and is a composite nitride layer of Al, Cr, Si, Mo, and S that satisfies X + Y + Z + Q + R = 1.
A coated tool (surface coated cutting tool) that exhibits excellent chipping resistance and wear resistance due to high-speed heavy cutting of heat-resistant alloys. "
It has the characteristics.

  Next, the reason why the numerical values of the composition change (Al, Cr, Si, Mo, S) N layer constituting the hard coating layer of the coated tool of the present invention are limited as described above will be described.

(A) Lower layer (Al, Cr, Si composite nitride layer)
The Al component in the Al, Cr and Si composite nitride layer (hereinafter referred to as “(Al, Cr, Si) N layer”) constituting the lower layer of the hard coating layer includes high temperature hardness and oxidation resistance, and the Cr component Has the effect of improving the high-temperature strength and the heat resistance of the Si component, and the lower layer maintains a high high-temperature hardness and oxidation resistance by relatively increasing the Al component content ratio. If the α value indicating the content ratio of Cr is less than 0.30 in terms of the total amount of Cr and Si (atomic ratio, the same shall apply hereinafter), the desired excellent high-temperature hardness and oxidation resistance cannot be ensured. On the other hand, when the α value indicating the proportion of Al exceeds 0.65, the high temperature strength rapidly decreases, and as a result, chipping (small chipping) is likely to occur. Therefore, the α value was determined to be 0.30 to 0.65, and C The β value indicating the proportion of Al and Si occupies the total amount of Al and Si. If the β value is less than 0.30, the predetermined high-temperature strength cannot be ensured, and chipping is likely to occur, while the β value is 0.65. When the value exceeds 1, the high temperature hardness has a clear tendency to appear, so the β value is set to 0.30 to 0.65, and the γ value indicating the proportion of Si is the total amount of Al and Cr. If the ratio is less than 0.01, a predetermined heat resistance improvement effect cannot be expected. On the other hand, if the γ value exceeds 0.10, a predetermined high temperature hardness and high temperature strength can be secured. Since it became impossible, the γ value was set to 0.01 to 0.10.
Furthermore, if the average layer thickness is less than 1 μm, the excellent high temperature hardness, oxidation resistance, high temperature strength and heat resistance cannot be imparted to the hard coating layer over a long period of time, resulting in a short tool life. When the average layer thickness exceeds 3 μm, chipping is likely to occur. Therefore, the average layer thickness was set to 1 to 3 μm.

(B) Al, Cr, Si content ratio of Al-Cr-Si highest content point in upper layer (composition change (Al, Cr, Si, Mo, S) N layer) Composition change (Al, Cr, Si, Mo, The Al component, Cr component and Si component in the S) N layer have the same action as in the lower layer, and the Mo component and S component are mostly present in the form of MoS _{2 in} the upper layer. It has the effect of improving the lubricity with the work piece chips. In other words, the Al-Cr-Si highest content point where the content ratio of Al, Cr, Si components is relatively high has excellent high temperature hardness, heat resistance, oxidation resistance, and high temperature strength, but the Al content ratio (X When the value is less than 0.40, the minimum required high-temperature hardness, heat resistance, and oxidation resistance for the hard coating layer cannot be maintained, and the Cr content ratio (Y value) is 0.00. If it is less than 30, chipping may occur due to insufficient high-temperature strength, and if the Si content (Z value) is less than 0.05, improvement in heat resistance of the hard coating layer cannot be expected. . On the other hand, the Al content ratio (X value) exceeded 0.60, the Cr content ratio (Y value) exceeded 0.50, or the Si content ratio (Z value) exceeded 0.10. In such a case, since the Mo content (Q value) and the S content (R value) are too small, it becomes impossible to improve the lubricity with respect to the work piece chips. The content ratio (X value) is 0.40 to 0.60, the Cr content ratio (Y value) is 0.30 to 0.50, the Si content ratio (Z value) is 0.05 to 0.10, Respectively.
In addition, the content ratio (Q value) of the Mo component and the content ratio (R value) of the S component at the highest Al-Cr-Si content point are excellent while maintaining high temperature hardness, oxidation resistance, high temperature strength and heat resistance. In order to exhibit excellent lubricity, it is necessary to set the ranges of 0.01 ≦ Q ≦ 0.10 and 0.01 ≦ R ≦ 0.10, and X, Y, Z, Q, and R are The numerical value must satisfy X + Y + Z + Q + R = 1.

(C) Mo and S content ratio of Mo-S highest content point in upper layer (composition change (Al, Cr, Si, Mo, S) N layer) Composition change ( The Al, Cr, Si, Mo, S) N layer has excellent lubricity, but the hard coating layer has not only these properties but also high temperature hardness, oxidation resistance, Since it is necessary to provide high-temperature strength and heat resistance as a matter of course, the Mo content (Q value) and S content (R value) at the Mo-S highest content point are the total amount of Al, Cr, Si, Mo, and S. The ratios (atomic ratios) of 0.25 to 0.40 and 0.40 to 0.55 were determined respectively.
That is, when the Mo content (Q value) exceeds 0.40 or the S content (R value) exceeds 0.55, the Al in the (Al, Cr, Si, Mo, S) N layer , Cr, Si component content decreases, as a result, high-temperature hardness, oxidation resistance, high-temperature strength, heat resistance becomes insufficient, while Mo content (Q value) is less than 0.25, Alternatively, when the S content ratio (R value) is less than 0.40, the content ratio of Mo and S in the (Al, Cr, Si, Mo, S) N layer is too small, and an improvement in lubricity is expected. The Mo content (Q value) is 0.25 to 0.40, and the S content (R value) is 0.40 to 0.55 (both atomic ratios). Determined.
In addition, the Al component content ratio (X value), Cr component content ratio (Y value), and Si component content ratio (Z value) at the Mo-S highest content point are the minimum required for high-speed heavy cutting of heat-resistant alloys. 0.05 ≦ X ≦ 0.20, 0.05 ≦ Y ≦ 0.20, 0.001 ≦ Z ≦ 0... From the viewpoint of having high-temperature hardness, oxidation resistance, high-temperature strength, and heat resistance. The range of 03 is required, and X, Y, Z, Q, and R must be numerical values satisfying X + Y + Z + Q + R = 1.

(D) Spacing between Al-Cr-Si highest content point and Mo-S highest content point The upper layer of the hard coating layer of the present invention has a concentration of components constituting nitrides in the layer thickness direction. Since it changes continuously from the Al-Cr-Si highest content point to the Mo-S highest content point and from the Mo-S highest content point to the Al-Cr-Si highest content point, Compared to a hard coating layer composed of a multi-layered structure in which the concentration changes discontinuously, there is no risk of delamination between the upper layers, but the Al-Cr-Si highest content point and Mo-S highest If the interval between contained points is less than 0.03 μm, it is difficult to clearly form each point with the above composition. As a result, each layer has a desired high temperature hardness, high temperature strength, heat resistance, and oxidation resistance. In addition, the lubricity cannot be ensured, and the interval is 0. If it exceeds 1 μm, the disadvantage of each point, that is, if the Mo-S maximum content point is insufficient high temperature hardness, high temperature strength, oxidation resistance and heat resistance, and if the Al-Cr-Si maximum content point Insufficient lubricity appears locally in the layer, which makes it easier for chipping to occur on the cutting edge and promotes the progress of wear. It was set to 1 μm.
In addition, the space | interval between the Al-Cr-Si highest content point and the Mo-S highest content point is the arc ion plating (AIP) apparatus for (Al, Cr, Si) N vapor deposition, and the magnetron sputtering (SP) for Mo-S vapor deposition. ) When forming a vapor deposition film by performing arc ion plating and sputtering at the same time using a vapor deposition apparatus provided with an apparatus, for example, it can be adjusted by controlling the rotational speed of a rotary table equipped with a tool base. Therefore, by appropriately setting the rotation speed of the turntable, the composition change (Al, Cr) in which the interval between the Al-Cr-Si highest content point and the Mo-S highest content point becomes a desired value within the above numerical range. , Si, Mo, S) N layers can be easily formed.
Further, the upper layer made of the composition change (Al, Cr, Si, Mo, S) N layer has excellent adhesion to the lower layer made of the (Al, Cr, Si) N layer, and has a high bonding strength. Since the adhesion and bonding strength of the lower layer to the tool base are also large, the coated tool of the present invention has a very strong bonding strength of the hard coating layer to the tool base.

(E) Average layer thickness of upper layer If the average layer thickness of the upper layer composed of composition change (Al, Cr, Si, Mo, S) N layer is less than 1 μm, the hard coating layer has a desired high-temperature hardness, high-temperature strength, Heat resistance, oxidation resistance and lubricity cannot be ensured over a long period of time, and as a result, improvement in chipping resistance and wear resistance in high speed heavy cutting of heat resistant alloys cannot be expected. If the average layer thickness exceeds 8 μm, chipping is likely to occur at the cutting edge, so the average layer thickness was set to 1 to 8 μm.

  In the coated tool of the present invention, the (Al, Cr, Si) N layer constituting the lower layer of the hard coating layer has excellent high-temperature hardness, high-temperature strength, heat resistance, and oxidation resistance. The composition change (Al, Cr, Si, Mo, S) N layer constituting the upper layer of the material has excellent lubricity in addition to excellent high temperature hardness, high temperature strength, heat resistance, and oxidation resistance, Furthermore, since the bonding strength between the hard coating layer and the tool base is very strong, heat-resistant alloys such as Ti-base alloys, Ni-base alloys, and Co-base alloys are accompanied by a large amount of heat and are large relative to the cutting edge. Even when processing is performed under high-speed heavy cutting conditions where a load is applied, excellent chipping resistance and wear resistance are exhibited over a long period of time without causing welding or partial wear.

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

WC powder, TiC powder, ZrC powder, VC powder, TaC powder, NbC powder, Cr ₃ C ₂ powder, TiN powder, TaN powder, and Co powder all having an average particle diameter of 1 to 3 μm are prepared as raw material powders. These raw material powders are blended in the composition shown in Table 1, wet mixed by a ball mill for 72 hours, dried, and then pressed into a green compact at a pressure of 100 MPa. Medium, sintered at 1400 ° C for 1 hour, after sintering, WC-based carbide with honing of R: 0.03 on the cutting edge and chip shape of ISO standard CNMG120408 Alloy tool bases A-1 to A-10 were formed.

In addition, as raw material powders, TiCN (mass ratio, TiC / TiN = 50/50) powder, Mo ₂ C powder, ZrC powder, NbC powder, TaC powder, WC, all having an average particle diameter of 0.5 to 2 μm. Prepare powder, Co powder, and Ni powder, mix these raw material powders into the composition shown in Table 2, wet mix for 24 hours with a ball mill, dry, and press-mold into green compact at 100 MPa pressure The green compact was sintered in a nitrogen atmosphere of 2 kPa at a temperature of 1500 ° C. for 1 hour. After sintering, the cutting edge portion was subjected to a honing process of R: 0.03 to meet ISO standards / Tool bases B-1 to B-6 made of TiCN base cermet having a chip shape of CNMG120408 were formed.

(A) The above-mentioned tool bases A1 to A10 and B1 to B6 are each ultrasonically cleaned in acetone and dried, and the vapor deposition apparatus provided with the arc ion plating apparatus and the magnetron sputtering apparatus shown in FIG. An Al—Cr—Si alloy having various composition as a cathode electrode (evaporation source) of the arc ion plating apparatus on one side and a magnetron on the other side. MoS ₂ is mounted as a target (evaporation source) for the sputtering apparatus, and metal Ti for bombard cleaning is also mounted. First, the apparatus is evacuated and kept at a vacuum of 0.5 Pa or less, and the apparatus is heated to 500 ° C. After applying heating, a DC bias voltage of −1000 V is applied to the tool base that rotates while rotating on the rotary table. In addition, a current of 100 A is passed between the metal Ti of the cathode electrode and the anode electrode to generate an arc discharge, thereby cleaning the tool base surface with Ti bombardment,
(B) Next, nitrogen gas is introduced as a reaction gas into the apparatus to form a reaction atmosphere of 2 Pa, and a DC bias voltage of −100 V is applied to the tool base that rotates while rotating on the rotary table, An arc discharge is generated by passing a current of 90 A between the cathode electrode and the anode electrode, and an (Al, Cr, Si) N layer having the target composition and target layer thickness shown in Tables 3 and 4 is formed on the surface of the tool base. A lower layer consisting of
(C) Next, a DC bias voltage of −100 V is applied to the rotating tool base while rotating on the rotary table while the apparatus is maintained in a 2 Pa nitrogen gas atmosphere, and the cathode electrode and the anode electrode are At the same time, a current of 90 A is passed to generate an arc discharge, and at the same time, a pulse power of 3 kW is applied from a pulse power source to the MoS ₂ target to sputter MoS ₂ .
(D) Al-Cr-Si highest content point and Mo-S highest content point of the target composition shown in Tables 3 and 4 alternately on the surface of the tool base rotating while rotating on the rotary table, It exists repeatedly at the target intervals shown in Tables 3 and 4, and from the Al-Cr-Si highest content point to the Mo-S highest content point, from the Mo-S highest content point to the Al-Cr-Si highest It has a component concentration distribution structure in which the content ratios of Al, Cr, Si, Mo, and S continuously change to the content point, and the compositional change of the target layer thickness (Al , Cr, Si, Mo, S) By depositing an upper layer composed of an N layer, the inventive coated tools 1 to 16 having a throwaway tip shape defined in ISO · CNMG120408 were produced.
In addition, in the said Example, the target space | interval of the Al-Cr-Si highest content point and Mo-S highest content point is predetermined | prescribed by changing the rotational speed of a rotary table within the range of 0.5-10 rpm. The target interval value was adjusted.

For comparison purposes, these tool bases A1 to A10 and B1 to B6 are ultrasonically cleaned in acetone and dried.
The above-mentioned tool base is inserted into the arc ion plating apparatus schematically shown in FIG. 2, and the inside of the apparatus is heated to a temperature of about 500 ° C. with a heater, and the Al—Cr—Si having a predetermined composition with the anode electrode An arc discharge is generated between the cathode electrode (evaporation source) and a current of about 90 A. Simultaneously, nitrogen gas is introduced into the apparatus as a reaction gas to form a reaction atmosphere of about 2 Pa. Is a compositionally uniform (Al, Cr, Si) N layer having the target composition and target layer thickness shown in Tables 5 and 6 on the surface of the tool base under the condition that a bias voltage of about −100 V is applied. The conventional coated tools 1 to 16 having a throwaway tip shape were produced by vapor-depositing a hard coating layer made of

Next, in the state where each of the above-mentioned various coated chips is screwed to the tip of the tool steel tool with a fixing jig, the present coated chips 1-16 and the conventional coated chips 1-16,
Work material: Co-based alloy circle having a composition of Co-20% Cr-15% W-10% Ni-1.5% Mn-1% Si-1% Fe-0.12% C in mass%. rod,
Cutting speed: 60 m / min. ,
Cutting depth: 1.5 mm,
Feed: 0.45 mm / rev. ,
Cutting time: 10 minutes,
Dry-type high-speed high-feed continuous cutting test of the Co-based alloy under the conditions (cutting conditions A) (normal cutting speed and feed are 30 m / min. And 0.25 mm / rev., Respectively),
Work material: Round bar with four longitudinal grooves at equal intervals in the longitudinal direction of a Ti-based alloy having a composition of Ti-3% Al-2.5% V in mass%,
Cutting speed: 65 m / min. ,
Cutting depth: 1.2 mm,
Feed: 0.50 mm / rev. ,
Cutting time: 5 minutes,
A dry high-speed high-feed intermittent cutting test of a Ti-based alloy under the following conditions (cutting condition B) (normal cutting speed and feed are 35 m / min. And 0.25 mm / rev., Respectively),
Work material: Ni having a composition of Ni-19% Cr-18.5% Fe-5.2% Cd-5% Ta-3% Mo-0.9% Ti-0.5% Al in mass%. Base alloy round bar,
Cutting speed: 70 m / min. ,
Cutting depth: 1.4 mm,
Feed: 0.30 mm / rev. ,
Cutting time: 10 minutes,
A dry high-speed, high-feed continuous cutting test (normal cutting speed and feed are 35 m / min. And 0.20 mm / rev., Respectively) of the Ni-based alloy under the above conditions (cutting conditions C) In the cutting test, the flank wear width of the cutting edge was measured. The measurement results are shown in Table 7.

As raw material powders, medium coarse WC powder having an average particle diameter of 5.5 μm, fine WC powder of 0.8 μm, TaC powder of 1.3 μm, NbC powder of 1.2 μm, ZrC of 1.2 μm Powder, 2.3 μm Cr ₃ C ₂ powder, 1.5 μm VC powder, 1.0 μm (Ti, W) C [by mass ratio, TiC / WC = 50/50] powder, and 1 Prepare 8 μm Co powder, mix these raw material powders with the composition shown in Table 8, add wax, ball mill in acetone for 24 hours, dry under reduced pressure, and press at a pressure of 100 MPa. The green compacts were press-molded, and these green compacts were heated to a predetermined temperature in the range of 1370 to 1470 ° C. at a rate of temperature increase of 7 ° C./min in a 6 Pa vacuum atmosphere. After holding at temperature for 1 hour, sintering under furnace cooling conditions Then, three types of round rod sintered bodies for forming a tool base having diameters of 8 mm, 13 mm, and 26 mm are formed, and further, the three types of round bar sintered bodies are ground and are shown in Table 7. In combination, the diameter x length of the cutting edge is 6 mm x 13 mm, 10 mm x 22 mm, and 20 mm x 45 mm, respectively, and each is made of a WC-based cemented carbide with a 4-flute square shape with a twist angle of 45 degrees Tool bases (end mills) C-1 to C-8 were produced.

  Next, the surfaces of these tool substrates (end mills) C-1 to C-8 were ultrasonically cleaned in acetone and dried, and the arc ion plating apparatus and magnetron sputtering apparatus shown in FIG. 1 were also provided. First, a lower layer composed of an (Al, Cr, Si) N layer having a target composition and a target layer thickness shown in Table 9 was formed by vapor deposition under the same conditions as in Example 1 above. The Al-Cr-Si highest content point and Mo-S highest content point of the target composition also shown in Table 9 along the layer thickness direction are alternately present at the target interval also shown in Table 9, and From the Al-Cr-Si highest content point to the Mo-S highest content point, from the Mo-S highest content point to the Al-Cr-Si highest content point, the content ratio of Al, Cr, Si, Mo, S Changes continuously The coated tool of the present invention is formed by vapor-depositing a hard coating layer having a component concentration distribution structure and comprising a target layer thickness composition change (Al, Cr, Si, Mo, S) N layer also shown in Table 9 The present invention coated end mills 1 to 8 were produced respectively.

  For comparison purposes, the surfaces of the tool bases (end mills) C-1 to C-8 are ultrasonically cleaned in acetone and dried, and then loaded into the arc ion plating apparatus shown in FIG. Then, under the same conditions as in Example 1, the surface of the tool base (end mill) C-1 to C-8 has a compositional uniformity (Al, having the target composition and target layer thickness shown in Table 10). Conventional coating end mills 1 to 8 as conventional coating tools were manufactured by vapor-depositing a hard coating layer composed of a Cr, Si) N layer, respectively.

Next, of the present invention coated end mills 1-8 and the conventional coated end mills 1-8,
About this invention coated end mills 1-3 and conventional coated end mills 1-3,
Work material-planar dimensions: 100 mm × 250 mm, thickness: 50 mm, and a Ti-based alloy plate material having a composition of Ti-6% Al-4% V in mass%,
Cutting speed: 60 m / min. ,
Groove depth (cut): 3.0 mm,
Table feed: 650 mm / min,
Ti-base alloy dry high-speed high-feed groove cutting test (normal cutting speed and table feed are 30 m / min. And 400 mm / min, respectively),
About this invention coated end mills 4-6 and conventional coated end mills 4-6,
Work Material-Plane Dimensions: 100mm x 250mm, Thickness: 50mm, Mass%, Co-23% Cr-6% Mo-2% Ni-1% Fe-0.6% Si-0.4% C A Co-base alloy plate having the composition:
Cutting speed: 65 m / min. ,
Groove depth (cut): 4.0 mm,
Table feed: 550 mm / min,
Co-base alloy dry high-speed high-feed grooving test (normal cutting speed and table feed are 35 m / min. And 350 mm / min, respectively),
For the coated end mills 7 and 8 of the present invention and the conventional coated end mills 7 and 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-base alloy plate material having a composition of% Ti-0.5% Al,
Cutting speed: 70 m / min. ,
Groove depth (cut): 5.5 mm,
Table feed: 550 mm / min,
Ni-base alloy dry high-speed high-feed groove cutting test under normal conditions (normal cutting speed and table feed are 35 m / min. And 350 mm / min, respectively)
In each groove cutting test, 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 9 and 10, respectively.

  The diameters produced in Example 2 above were 8 mm (for forming the tool bases C-1 to C-3), 13 mm (for forming the tool bases C-4 to C-6), and 26 mm (tool bases C-7 and C). -8 for forming), and from these three types of round bar sintered bodies, the diameter x length of the groove forming part is 4 mm x 13 mm (tool base D) by grinding. −1 to D-3), 8 mm × 22 mm (tool base D-4 to D-6), and 16 mm × 45 mm (tool bases D-7 and D-8), and all having a twist angle of 30 degrees 2 WC-base cemented carbide tool bases (drills) D-1 to D-8 having a single-blade shape were produced, respectively.

  Then, the cutting edges of these tool bases (drills) D-1 to D-8 are subjected to honing, ultrasonically cleaned in acetone, and dried, and the arc ion plating apparatus shown in FIG. A lower layer composed of an (Al, Cr, Si) N layer having a target composition and a target layer thickness shown in Table 11 under the same conditions as in Example 1 above. After that, the Al-Cr-Si highest content point and the Mo-S highest content point of the target composition shown in Table 11 are alternately arranged along the layer thickness direction at the target interval also shown in Table 11. Al, Cr, Si, Mo, repeatedly present and from the highest Al-Cr-Si content point to the highest Mo-S content point, from the highest Mo-S content point to the highest Al-Cr-Si content point , S content ratio By vapor-depositing a hard coating layer having a continuously varying component concentration distribution structure and comprising a target layer thickness composition change (Al, Cr, Si, Mo, S) N layer also shown in Table 11 The inventive coated drills 1 to 8 as the inventive coated tool were produced, respectively.

  In addition, for the purpose of comparison, honing is performed on the surfaces of the above-mentioned tool bases (drills) D-1 to D-8, ultrasonic cleaning is performed in acetone, and the surfaces are loaded into an arc ion plating apparatus Then, under the same conditions as in Example 1 above, the surfaces of the tool bases (drills) D-1 to D-8 have a compositional uniformity (Al, having the target composition and target layer thickness shown in Table 12). Conventional coating drills 1 to 8 as conventional coating tools were manufactured by vapor-depositing a hard coating layer composed of a Cr, Si) N layer.

Next, among the above-mentioned present invention coated drills 1-8 and conventional coated drills 1-8,
About this invention coated drill 1-3 and conventional coated drill 1-3,
Work material-planar dimensions: 100 mm × 250 mm, thickness: 50 mm, and a Ti-based alloy plate material having a composition of Ti-6% Al-4% V in mass%,
Cutting speed: 60 m / min. ,
Feed: 0.35 mm / rev,
Hole depth: 6 mm,
Wet high-speed high-feed drilling test of Ti-based alloy under the conditions of (normal cutting speed and feed are 35 m / min. And 0.2 mm / rev., Respectively),
About this invention coated drill 4-6 and conventional coated drills 4-6,
Work Material-Planar Dimensions: 100 mm × 250 mm, Thickness: 50 mm, Mass%, Co-20% Cr-20% Ni-4% Mn-4% W-4% Cd-3% Fe-1.5 Co-base alloy plate material having a composition of% Mn-0.7% Si-0.38% C,
Cutting speed: 65 m / min. ,
Feed: 0.45 mm / rev,
Hole depth: 15 mm,
Wet high-speed high-feed drilling test of a Co-based alloy under the conditions (normal cutting speed and feed are 30 m / min. And 0.25 mm / rev., Respectively),
About this invention covering drills 7 and 8 and conventional covering drills 7 and 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-base alloy plate material having a composition of% Ti-0.5% Al-0.3% Si-0.2% Mn-0.05% Cu-0.04% C,
Cutting speed: 70 m / min. ,
Feed: 0.4 mm / rev,
Hole depth: 20 mm,
Wet high-speed high-feed drilling test of Ni-based alloy under the conditions of (normal cutting speed and feed are 40 m / min. And 0.25 mm / rev., Respectively),
In each wet high-speed high-feed drilling cutting test (using water-soluble cutting oil), the number of drilling operations until the flank wear width of the tip cutting edge surface reached 0.3 mm was measured. The measurement results are shown in Tables 11 and 12, respectively.

  As a result, the coated chips 1 to 16 of the present invention, the coated end mills 1 to 8 of the present invention and the lower layers of the hard coated layers of the coated drills 1 to 8 are obtained (Al, Cr, Si) composition of the N layer and the upper layer (Al, Cr, Si, Mo, S) The composition of the Al-Cr-Si highest content point and Mo-S highest content point of the N layer was measured using a transmission electron microscope. When measured by the energy dispersive X-ray analysis method used, it showed substantially the same composition as each target composition. Moreover, the compositionally uniform (Al, Cr, Si) N layer constituting the hard coating layers of the conventional coated chips 1 to 16, the conventional coated end mills 1 to 8, and the conventional coated drills 1 to 8 as conventional coated tools. When the composition was measured by energy dispersive X-ray analysis using a transmission electron microscope, it 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 7 and 9 to 12, the coated tool of the present invention is a high-speed heavy load that involves high heat generation of a heat-resistant alloy such as a Ti-base alloy, a Ni-base alloy, and a Co-base alloy and that places a large load on the cutting blade. Even when used for cutting under cutting conditions, the composition change (Al, Cr, Si, Mo) constituting the lower layer (Al, Cr, Si) N layer and the upper layer of the hard coating layer , S) The N layer as a whole has excellent high temperature hardness, oxidation resistance, high temperature strength, heat resistance and excellent lubricity, and the hard coating layer has strong bonding strength with the tool base. As a result, there is no occurrence of welding and uneven wear, while excellent chipping resistance and wear resistance are exhibited over a long period of time, while the hard coating layer is compositionally uniform (Al, Cr, Si) In the conventional coated tool composed of N layers, high heat is applied by high speed heavy cutting. By involving raw, welding, uneven wear occurs and this is apparent that lead to a relatively short time service life due.

  As described above, the coated tool of the present invention can be used for cutting of general steel, ordinary cast iron, etc., as well as Ti-based alloys, Ni-based alloys, and Co-based materials that generate high heat and impose a heavy load on the cutting blade. Even when used for high-speed heavy cutting of heat-resistant alloys such as alloys, it exhibits excellent chipping resistance and excellent wear resistance over a long period of time, and exhibits excellent cutting performance. It can be used satisfactorily for FA, labor saving and energy saving of cutting, and cost reduction.

The vapor deposition apparatus which used together the arc ion plating apparatus and magnetron sputtering apparatus which were used for forming the hard coating layer which comprises the coating tool of this invention is shown, (a) is a schematic plan view, (b) is a schematic front view. It is. It is a schematic explanatory drawing of the arc ion plating apparatus used in forming the hard coating layer which comprises a conventional coating tool.

Claims (1)

On a rotary table of a vapor deposition apparatus in which a tungsten carbide-based cemented carbide or titanium carbonitride-based cermet is provided with an Al—Cr—Si alloy as a cathode electrode on one side and a MoS ₂ target on the other side A lower layer and an upper layer are formed on the surface of the tool base by arc ion plating on the Al-Cr-Si alloy cathode electrode side and sputtering on the MoS ₂ target side while rotating the tool base on a rotary table. In a surface-coated cutting tool in which a hard coating layer consisting of layers is formed by vapor deposition,
The lower layer has an average layer thickness of 1 to 3 μm deposited by arc ion plating, and the content ratios (however, the atomic ratio) of the Al component, Cr component, and Si component are α, β, respectively. Al and Cr satisfying α + β + γ = 1 when α is 0.30 to 0.65, β is 0.30 to 0.65, γ is 0.01 to 0.10, and And Si composite nitride layer,
The upper layer is a composite nitride layer of Al, Cr, Si, Mo, and S having an average layer thickness of 1 to 8 μm formed by simultaneous vapor deposition of the arc ion plating and the sputtering, The upper layer is
(A) Along the layer thickness direction of the upper layer, the Al—Cr—Si highest content point formed in the vicinity of the Al—Cr—Si alloy cathode electrode and the Mo—S highest content formed in the vicinity of the MoS ₂ target And dots are alternately present at intervals of 0.03 to 0.1 μm,
(B) From the highest Al-Cr-Si content point to the highest Mo-S content point, from the highest Mo-S content point to the highest Al-Cr-Si content point, Al, Cr, Si, Mo, S Have a component concentration distribution structure in which the content ratio of each continuously changes,
(C) Al component, Cr component, Si component, Mo component and S component at the highest Al-Cr-Si content point formed in the vicinity of the Al-Cr-Si alloy cathode electrode, the content ratio (however, atom Ratio) is represented by X, Y, Z, Q, and R, respectively, X is 0.40 to 0.60, Y is 0.30 to 0.50, Z is 0.05 to 0.10, Q is 0.01 to 0.10, R is 0.01 to 0.10, and X + Y + Z + Q + R = 1 is satisfied,
(D) The Al component, Cr component, Si component, Mo component and S component at the Mo-S highest content point formed in the vicinity of the MoS ₂ target have their content ratios (however, the atomic ratio) set to X, When represented by Y, Z, Q, and R, X is 0.05 to 0.20, Y is 0.05 to 0.20, Z is 0.001 to 0.03, and Q is 0.25 to 0. .40, R is 0.40 to 0.55, and is a composite nitride layer of Al, Cr, Si, Mo, and S that satisfies X + Y + Z + Q + R = 1.
A surface-coated cutting tool that exhibits excellent chipping resistance and wear resistance in a high-speed heavy cutting of a heat-resistant alloy.

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