JP2008105107A - Surface coated cutting tool with hard coated layer showing excellent wear resistance in high speed cutting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface coated cutting tool with a hard coated layer, which shows excellent wear resistance in high speed cutting. <P>SOLUTION: The surface coating cutting tool is constituted by coating a surface of a tool basic body formed by tungsten carbide cemented carbide or titanium carbon nitride cermet with a composition change (Al, Cr, Si, Ti, B) N layer having average thickness of 1-5 μm and having the points containing the maximum amount of Al-Cr-Si and the points containing the maximum amount of Ti-B existent alternately and repeatedly at a predetermined interval along the direction of layer thickness. The percentages of Al, Cr, Si, Ti, and B contained at the points containing the maximum amount of Al-Cr-Si are 0.40-0.60, 0.30-0.45, 0.005-0.10, 0.02-0.10, and 0.01-0.10, respectively, and the percentages of Al, Cr, Si, Ti, and B at the points containing the maximum amount of Ti-B are 0.05-0.20, 0.05-0.20, 0.001-0.03, 0.25-0.40, and 0.40-0.55, respectively. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  This invention provides excellent wear resistance with a hard coating layer even when cutting a highly reactive material with high hardness, such as an Al alloy, under high-speed cutting conditions with high heat generation. The present invention relates to a surface-coated cutting tool to be exhibited (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 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. A coated tool formed by physical vapor deposition of a nitride of Cr, Si, Ti, and B (hereinafter referred to as (Al, Cr, Si, Ti, B) N) is known, and the coated tool is hard. The coating layer has excellent high-temperature hardness, heat resistance, and high-temperature strength, and exhibits excellent cutting performance when used for cutting various general steels and ordinary cast iron under normal conditions. It has been known.

Further, the above-mentioned coated tool, for example, the above-mentioned tool base is loaded into an arc ion plating apparatus which is a kind of physical vapor deposition apparatus shown schematically in FIG. A cathode electrode (evaporation) in which an anode electrode and an alloy of Al, Cr, Si, Ti, and B (hereinafter referred to as an Al-Cr-Si-Ti-B alloy) having a predetermined composition are set in a state heated to For example, an arc discharge is generated under the condition of current: 90 A, and nitrogen gas is introduced into the apparatus as a reaction gas to form a reaction atmosphere of 2 Pa, for example. It is also known that it is manufactured by vapor-depositing a hard coating layer composed of the above (Al, Cr, Si, Ti, B) N layer on the surface of the tool base under a condition where a bias voltage of 100 V is applied. That.
JP 2003-71611 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 a high-speed, high-altitude heat-generating material with high hardness and extremely high reactivity, such as an Al-Si alloy. When used for cutting conditions, the reaction wear between the hard coating layer and the highly reactive work material proceeds rapidly due to high heat generation, and lubricity with the work material. As a result, the service life is reached in a relatively short time.

In view of the above, the inventors of the present invention focused on the above-mentioned conventional coated tool in order to develop a coated tool that exhibits excellent wear resistance with a hard coating layer, particularly in high-speed cutting, and researched. As a result of
(A) For example, an arc ion plating apparatus and titanium boride (hereinafter referred to as “Al, Cr, Si) N” having a structure shown in a schematic plan view in FIG. 1A and a schematic front view in FIG. Using a vapor deposition apparatus provided with a magnetron sputtering apparatus for vapor deposition (denoted by TiB ₂ ), a rotary table for mounting a tool substrate (for example, a carbide substrate) is provided in the center of the device, and a predetermined value is provided on one side of the rotary table. Arc ion plating apparatus for (Al, Cr, Si) N deposition having a cathode electrode (evaporation source) made of an Al—Cr—Si alloy having a composition, and a target made of a TiB ₂ sintered body on the other side (evaporation source) The Ti-B vapor deposition magnetron sputtering apparatus equipped with a) is disposed oppositely, and is placed on the rotary table for mounting the tool base at a position spaced apart from the central axis in a radial direction. The tool base is mounted in a ring shape, and the atmosphere in the apparatus is changed to a nitrogen atmosphere in this state. The rotary table is rotated, and the tool base itself is rotated for the purpose of uniforming the thickness of the hard coating layer to be formed. However, an arc discharge is generated between the cathode electrode (evaporation source) and the anode electrode made of the Al—Cr—Si alloy of the above-described (Al, Cr, Si) N deposition arc ion plating apparatus, and at the same time, When TiB ₂ is sputtered by applying a pulse voltage to a target (evaporation source) made of a TiB ₂ sintered body of a Ti-B vapor deposition magnetron sputtering apparatus arranged oppositely, Al, Cr, and Si are formed by arc ion plating and sputtering. A nitride layer of Ti and B (hereinafter referred to as (Al, Cr, Si, Ti, B) N layer) is deposited and formed The nitride layer is relatively close to the position where the tool base disposed on the turntable is closest to the cathode electrode (evaporation source) of the Al—Cr—Si alloy on the one side, A region where the content ratio of Cr and Si is maximized and the content ratio of Ti and B is minimized (hereinafter referred to as the Al-Cr-Si highest content point) is formed, and the tool base is formed on the other side. In the position closest to the TiB ₂ sintered body target (evaporation source), the content ratio of Ti and B in the vapor deposition layer is relatively maximum and the content ratio of Al, Cr, and Si is minimum. A region (hereinafter referred to as a Ti-B highest content point) is formed, and the Al-Cr-Si highest content point and the Ti-B highest content point are formed in the layer along the layer thickness direction by the rotation of the rotary table. With a predetermined interval according to the rotation speed of the rotary table It appears repeatedly, and from the Al-Cr-Si highest content point to the Ti-B highest content point, from the Ti-B highest content point to the Al-Cr-Si highest content point, Al, Cr, Si, Ti A vapor deposition layer having a component concentration distribution structure in which the B content changes continuously (hereinafter referred to as composition change (Al, Cr, Si, Ti, B) N layer) is formed.

(B) In the hard coating layer composed of the above composition change (Al, Cr, Si, Ti, B) N layer, the Al component improves the high temperature hardness and oxidation resistance, and the Cr component improves the high temperature strength. The Si component improves the heat resistance, the Ti component further improves the high-temperature strength, and the B component has the effect of improving the lubricity and non-reactivity, and therefore relatively Al, Cr, Si. At the highest Al-Cr-Si content point, the hard coating layer composed of the above composition change (Al, Cr, Si, Ti, B) N layer has excellent high temperature hardness, oxidation resistance, and high temperature strength. However, on the other hand, since lubricity and non-reactivity are not sufficient, reactive wear is likely to occur under high-speed cutting conditions, so that the composition change (Al, Cr, Si, Ti, B) N layer Al- Lubricity at the highest content point of Cr-Si, In order to compensate for the lack of reactivity, the composition change (Al, Cr, Si, Ti, B) is performed by alternately interposing the highest content points of Ti-B having excellent lubricity and non-reactivity in the thickness direction. ) As a whole hard coating layer composed of N layer, it has excellent high temperature hardness, oxidation resistance, high temperature strength, heat resistance, lubricity and non-reactivity, and as a result, it reacts even under high speed cutting conditions To have excellent wear resistance without causing wear.
The research results shown in (a) and (b) above were obtained.

This invention was made based on the above research results,
A vapor deposition apparatus provided with a tool base made of tungsten carbide-based cemented carbide or titanium carbonitride-based cermet, an Al—Cr—Si alloy as a cathode electrode on one side, and a TiB ₂ sintered material as a target on the other side. The tool substrate is placed on a rotary table, and the tool substrate is rotated on the rotary table while arc ion plating on the Al—Cr—Si alloy cathode electrode side and sputtering on the TiB ₂ sintered material target side. In a surface-coated cutting tool in which a hard coating layer composed of a nitride layer of Al, Cr, Si, Ti, and B is formed on the surface by vapor deposition,
(A) The hard coating layer has an average layer thickness of 1 to 8 μm, and the highest Al—Cr—Si formed in the vicinity of the Al—Cr—Si alloy cathode electrode along the thickness direction of the hard coating layer. The content point and the Ti-B highest content point formed in the vicinity of the TiB ₂ sintered material target are alternately present at intervals of 0.005 to 0.1 μm,
(B) From the highest Al-Cr-Si content point to the highest Ti-B content point, from the highest Ti-B content point to the highest Al-Cr-Si content point, Al, Cr, Si, Ti, BC Have a component concentration distribution structure in which the content ratio of each continuously changes,
(C) Al component, Cr component, Si component, Ti component and B component at the highest Al-Cr-Si content point formed in the vicinity of the Al-Cr-Si alloy cathode electrode are the content ratio (however, the atom Ratio) is represented by X, Y, Z, Q, and R, respectively, X is 0.40 to 0.60, Y is 0.30 to 0.45 , Z is 0.005 to 0.10, Q is 0.02 to 0.10, R is 0.01 to 0.10, and X + Y + Z + Q + R = 1 is satisfied,
(D) Al component, Cr component, Si component, Ti component, and B component at the highest Ti-B content point formed in the vicinity of the TiB ₂ sintered material target, the content ratio (however, the atomic ratio), When represented by X, 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 0.00. 25 to 0.40, R is 0.40 to 0.55, and a composition change (Al, Cr, Si, Ti, B) N layer satisfying X + Y + Z + Q + R = 1 is formed by vapor deposition.
It is characterized by a coated tool (surface coated cutting tool) that exhibits excellent wear resistance with a hard coating layer in high-speed cutting.

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

(A) Al, Cr, Si content ratio of Al-Cr-Si highest content point Al in composition change (Al, Cr, Si, Ti, B) N layer improves high temperature hardness and oxidation resistance. Cr improves the high temperature strength, the Si component improves the heat resistance, the Ti component further improves the high temperature strength, and the B component even in high-speed cutting with high heat generation of the highly reactive work material, Suppresses the reactivity between the highly reactive work material and the hard coating layer and enhances the lubricity with the chips, so there is no chipping and long-term wear resistance is demonstrated. It becomes like this. Therefore, the Al-Cr-Si highest content point where the content ratio of Al, Cr, Si components is relatively high has excellent high temperature hardness, oxidation resistance, high temperature strength, and heat resistance, but the Al content ratio (X value) ) Is less than 0.40, the minimum required high temperature hardness and oxidation resistance for the hard coating layer cannot be maintained, and the Cr content (Y value) is less than 0.30. May cause chipping due to insufficient high-temperature strength. If the Si content (Z value) is less than 0.005, improvement in heat resistance cannot be expected. On the other hand, the Al content ratio (X value) exceeded 0.60, the Cr content ratio (Y value) exceeded 0.45 , or the Si content ratio (Z value) exceeded 0.10. In such a case, the Ti content ratio (Q value) and the B content ratio (R value) are too small, and in particular, the non-reactivity and lubricity of the hard coating layer cannot be secured. The Al content ratio (X value) is 0.40 to 0.60, the Cr content ratio (Y value) is 0.30 to 0.45 , and the Si content ratio (Z value) is 0.005 to 0.10. Respectively.
The content ratio (Q value) of the Ti component and the content ratio (R value) of the B component at the highest Al-Cr content point are the high temperature strength, non-reactivity and lubricity required for high-speed cutting of an Al alloy. In order to ensure, it is necessary to make the range 0.02 ≦ Q ≦ 0.10, 0.01 ≦ R ≦ 0.10, and X, Y, Z, Q, and R satisfy X + Y + Z + Q + R = 1. Must be a numeric value.

(B) Ti, B content ratio at the highest Ti-B content point At the Ti-B highest content point of the hard coating layer, the composition change (Al, Cr, Si, Ti, B) N layer has particularly excellent non-reactivity and Although it has lubricity, the hard coating layer naturally has not only these characteristics but also the minimum required high temperature hardness, oxidation resistance, high temperature strength, and heat resistance as a hard coating layer. -The Ti content ratio (Q value) and B content ratio (R value) at the highest B content point are ratios (atomic ratios) to the total amount of Al, Cr, Ti, and B, and are 0.25-0. 40, 0.40 to 0.55.
That is, when the Ti content ratio (Q value) exceeds 0.40 or the B content ratio (R value) exceeds 0.55, the Al in the (Al, Cr, Si, Ti, B) N layer , Cr content, Si content decreases, resulting in insufficient high-temperature hardness, oxidation resistance, high-temperature strength, heat resistance, and chipping (minute chipping) is likely to occur on the cutting edge. When the Ti content (Q value) is less than 0.25, or when the B content (R value) is less than 0.40, (Al, Cr, Si, Ti, B) of Ti in the N layer Since the content ratio becomes too small, further improvement in high-temperature strength cannot be expected, and non-reactivity and lubricity cannot be expected. Therefore, the Ti content ratio (Q value) is set to 0.25 to 0. .40, and the B content (R value) is 0.40 to 0.55 Re was also defined atomic ratio).
In addition, the content ratio (X value) of the Al component, the content ratio (Y value) of the Cr component, and the content ratio (Z value) of the Si component at the highest Ti-B content point are the minimum temperatures required for high-speed cutting. In order to ensure hardness, oxidation resistance, high temperature strength, and heat resistance, 0.05 ≦ X ≦ 0.20, 0.05 ≦ Y ≦ 0.20, 0.001 ≦ Z ≦ 0.03 In addition, X, Y, Z, Q, and R must be numerical values satisfying X + Y + Z + Q + R = 1.

(C) Spacing between Al-Cr-Si highest content point and Ti-B highest content point In the hard coating layer of the present invention, the concentration of the component constituting the nitride is Al-Cr over the layer thickness direction. -The highest Si content point is changed from the highest Ti-B content point, and the highest Ti-B content point to the highest Al-Cr-Si content point. Compared to a hard coating layer consisting of a multi-layered laminated structure that changes continuously, there is no risk of peeling between multiple layers, and the adhesion strength and bonding strength of the hard coating layer itself are very good. When the distance between the highest content point of Cr—Si and the highest content point of Ti—B is less than 0.005 μm, it is difficult to clearly form each point with the above composition. As a result, each layer has a desired high temperature. Hardness, oxidation resistance, high temperature strength, non-reactivity and lubrication If the distance exceeds 0.1 μm, the disadvantages of the respective points, that is, the highest content point of Ti-B, is high temperature hardness, oxidation resistance, high temperature strength and heat resistance. If the Al-Cr-Si maximum content point is insufficient, insufficient non-reactivity and lack of lubricity will appear locally in the layer, which may cause chipping on the cutting edge and progress of wear. Therefore, the interval was set to 0.005 to 0.1 μm.
The distance between the Al-Cr-Si highest content point and TiB highest containing point, (Al, Cr, Si) N deposition arc ion plating apparatus and TiB features the deposition apparatus ₂ deposition magnetron sputtering apparatus When forming a vapor deposition film by simultaneously performing arc ion plating and sputtering, the rotational speed of the rotary table can be adjusted by controlling the rotational speed of the rotary table on which the tool base is mounted. Is set appropriately, the composition change (Al, Cr, Si, Ti, B) in which the interval between the Al-Cr-Si highest content point and the Ti-B highest content point becomes a desired value within the above numerical range. The N layer can be easily formed.

(D) Average layer thickness When the average layer thickness is less than 1 μm, the hard coating layer can ensure the desired high temperature hardness, oxidation resistance, high temperature strength, heat resistance, non-reactivity and lubricity over a long period of time. As a result, improvement in wear resistance in high-speed cutting cannot be expected. On the other hand, if the average layer thickness exceeds 8 μm, chipping tends to occur on the cutting edge. Was set to 1 to 8 μm.

  In the coated tool of the present invention, the composition change (Al, Cr, Si, Ti, B) N layer constituting the hard coating layer as a whole has excellent high temperature hardness, oxidation resistance, high temperature strength, and heat resistance. In addition, because it also has excellent non-reactivity and lubricity, when processing hard and highly reactive Al alloy such as Al-Si alloy under high-speed cutting conditions with particularly large heat generation Even so, it exhibits excellent wear resistance over a long period of time.

  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-9 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-5 made of TiCN base cermet having a chip shape of CNMG120408 were formed.

Next, each of the tool bases A-1 to A-9 and B -1 to B-5 was ultrasonically cleaned in acetone and dried, and then the arc ion plating apparatus and magnetron shown in FIG. Al-Cr- having various component compositions as a cathode electrode (evaporation source) of the arc ion plating apparatus on one side mounted on a rotary table in a vapor deposition apparatus provided with a sputtering apparatus. A TiB ₂ sintered body is mounted as a target (evaporation source) for the Si alloy and the other side of the magnetron sputtering apparatus, and a metal Ti for bombard cleaning is also mounted. However, after heating the inside of the apparatus to 500 ° C. with a heater, a DC bias of −1000 V is applied to the tool base that rotates while rotating on the rotary table. A voltage is applied to cause a 100 A current to flow between the metal Ti of the cathode electrode and the anode electrode to generate an arc discharge, thereby cleaning the surface of the tool base 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, and the cathode An arc discharge is generated by passing a current of 90 A between the electrode and the anode electrode,
(C) At the same time, a pulse power of 3.0 kW is applied to the target of the TiB ₂ sintered body using a pulse power source to sputter TiB ₂ ,
(D) Al-Cr-Si highest content point and Ti-B 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 Ti-B highest content point, from the Ti-B highest content point to the Al-Cr-Si highest It has a component concentration distribution structure in which the content ratio of Al, Cr, Si, Ti, and B continuously changes to the content point, and further, the compositional change of the target layer thickness (Al , Cr, Si, Ti, B) The present invention coated tools 1 to 14 having a throwaway tip shape defined in ISO · CNMG120408 were produced by vapor-depositing a hard coating layer composed of an N layer.
In addition, in the said Example, the target space | interval of the Al-Cr-Si highest content point and the Ti-B 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 A-1 to A-9 and B -1 to B-5 were ultrasonically cleaned in acetone and dried, and the normal arc ions shown in FIG. Inserted into the plating apparatus, as the cathode electrode (evaporation source), Al-Cr-Si-Ti-B alloys with various component compositions were mounted, and bombard cleaning metal Ti was also mounted. The inside of the apparatus was heated to 500 ° C. with a heater while evacuating and maintaining a vacuum of 0.5 Pa or less, and then a DC bias voltage of −1000 V was applied to the tool base, so that the metal Ti and anode electrode of the cathode electrode A current of 100 A is passed between them to generate an arc discharge, thereby cleaning the surface of the tool substrate with Ti bombardment, and then introducing nitrogen gas as a reaction gas into the apparatus to form a reaction atmosphere of 2 Pa. Both the lower the bias voltage applied to the tool substrate to -100 V, the cathode electrode and flowing a 90A current between the anode electrode to generate arc discharge, the have tool substrate A-1 to A-9 And B-1 to B-5 are composed of compositionally uniform (Al, Cr, Si, Ti, B) N layers having the target compositions and target layer thicknesses shown in Tables 5 and 6. Similarly, the conventional coated tools 1 to 14 having the throwaway tip shape were manufactured by depositing the hard coating layer.

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 14 and the conventional coated chips 1 to 14 are as follows.
Work material: JIS A390 round bar,
Cutting speed: 300 m / min. ,
Cutting depth: 0.8 mm,
Feed: 0.05 mm / rev. ,
Cutting time: 4 minutes,
Dry high-speed continuous cutting test of aluminum alloy under the following conditions (cutting condition A) (normal cutting speed is 180 m / min.),
Work material: JIS / AC9B round bar,
Cutting speed: 260 m / min. ,
Cutting depth: 1.2 mm,
Feed: 0.1 mm / rev. ,
Cutting time: 5 minutes,
Dry high-speed continuous cutting test of aluminum alloy under the following conditions (cutting condition B) (normal cutting speed is 180 m / min.),
Work material: JIS / AC3A lengthwise equal 4 round grooves
Cutting speed: 280 m / min. ,
Cutting depth: 0.3 mm,
Feed: 0.1 mm / rev. ,
Cutting time: 3 minutes,
Were subjected to dry high-speed intermittent cutting test (normal cutting speed was 150 m / min.) Of aluminum alloy under the above conditions (cutting condition C), and the flank wear width of the cutting edge was measured in any cutting test. . 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 30 degrees Tool bases (end mills) C-1 to C-8 were produced.

Next, of these tool bases (end mills) C-1 to C-8 , the surfaces of the tool bases (end mills) C-1 to C-5, C-7, and C-8 are ultrasonically cleaned in acetone. In a dried state, the sample was inserted into a vapor deposition apparatus provided with the arc ion plating apparatus and magnetron sputtering apparatus shown in FIG. 1 and shown in Table 9 along the layer thickness direction under the same conditions as in Example 1 above. Al-Cr-Si highest content point and T-iB highest content point of the target composition to be alternately present repeatedly at the target intervals shown in Table 9, and from the Al-Cr-Si highest content point to the Ti -A component concentration distribution structure in which the content ratio of Al, Cr, Si, Ti, and B continuously changes from the highest content point of B and the highest content point of Ti-B to the highest content point of Al-Cr-Si. And also shown in Table 9 That the composition changes in the target layer thickness (Al, Cr, Si, Ti , B) by depositing form a hard coating layer consisting of N layers, the present invention coated end mills 1-7 as the present invention coated tool was produced, respectively.

For comparison purposes, the surfaces of the tool bases (end mills) C-1 to C-5, C-7, and C-8 are ultrasonically cleaned in acetone and dried, and are also shown in FIG. Table 10 shows the surface of tool bases (end mills) C-1 to C-5, C-7, and C-8 under the same conditions as in Example 1 above. By depositing a hard coating layer composed of a compositionally uniform (Al, Cr, Si, Ti, B) N layer having the target composition and target layer thickness shown, 7 were produced respectively.

Next, of the present invention coated end mills 1 to 7 and the conventional coated end mills 1 to 7 ,
About this invention coated end mills 1-3 and conventional coated end mills 1-3,
Work material-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / AC9B plate,
Cutting speed: 260 m / min. ,
Groove depth (cut): 5.0 mm,
Table feed: 280 mm / min,
Dry high-speed grooving test of aluminum alloy under the conditions (normal cutting speed is 150 m / min.),
For the coated end mills 4 and 5 of the present invention and the conventional coated end mills 4 and 5 ,
Work material-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / A390 plate,
Cutting speed: 280 m / min. ,
Groove depth (cut): 7.5 mm,
Table feed: 1000 mm / min,
Dry high-speed grooving test of aluminum alloy under the conditions (normal cutting speed is 150 m / min.),
For the coated end mills 6 and 7 of the present invention and the conventional coated end mills 6 and 7 ,
Work material-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / AC3A plate material,
Cutting speed: 300 m / min. ,
Groove depth (cut): 12.0 mm,
Table feed: 950 mm / min,
Dry-type high-speed grooving test of aluminum alloy under normal conditions (normal cutting speed is 150 m / min.)
In each groove cutting test, the cutting groove length was measured until the flank wear width of the outer peripheral blade of the cutting edge portion reached 0.2 mm, which is a guide for the service life. The measurement results are shown in Tables 9 and 10, respectively.

The diameters manufactured in Example 2 above were 8 mm (for forming the tool bases C-1 to C-3), 13 mm (for forming the tool bases D-5 and C-6), and 26 mm (for the 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-5, D-6), and 16 mm × 45 mm (tool base D-7, D-8), and each of 2 with a twist angle of 30 degrees Tool bases (drills) D-1 to D-3 and D-5 to D-8 made of a WC-base cemented carbide having a single blade shape were produced.

Next, honing is applied to the cutting edges of these tool bases (drills) D-1 to D-3, D-5 to D-8, and ultrasonic cleaning is performed in acetone. The Al-Cr-Si having the target composition shown in Table 11 along the layer thickness direction was placed under the same conditions as in Example 1 above, while being placed in a vapor deposition apparatus provided with both the arc ion plating apparatus and the magnetron sputtering apparatus shown. The highest content point and the Ti-B highest content point are alternately present repeatedly at the target intervals shown in Table 11, and from the Al-Cr-Si highest content point, the Ti-B highest content point, the Ti- It has a component concentration distribution structure in which the content ratio of Al, Cr, Si, Ti, B continuously changes from the highest B content point to the highest Al-Cr-Si content point, and is also shown in Table 11 Change in composition of target layer thickness (Al, Cr, Si, Ti , B) by depositing form a hard coating layer consisting of N layers, the present invention coated drill 1-7 as the present invention coated tool was produced, respectively.

In addition, for the purpose of comparison, honing is performed on the surfaces of the tool bases (drills) D-1 to D-3, D-5 to D-8, and ultrasonic cleaning is performed in acetone. Similarly, the surface of tool bases (drills) D-1 to D-3, D-5 to D-8 is charged in the normal arc ion plating apparatus shown in FIG. 2 under the same conditions as in the first embodiment. Further, by depositing a hard coating layer composed of a compositionally uniform (Al, Cr, Si, Ti, B) N layer having the target composition and target layer thickness shown in Table 12, as a conventional coating tool, Conventionally, the coated drills 1 to 7 were manufactured.

Then, among the present invention cover the drill 1-7 and the conventional coated drill 1-7,
About this invention coated drill 1-3 and conventional coated drill 1-3,
Work material-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / AC3A plate material,
Cutting speed: 150 m / min. ,
Feed: 0.1 mm / rev,
Hole depth: 10 mm,
Wet high-speed drilling test of aluminum alloy under the conditions (normal cutting speed is 80 m / min.),
About this invention coated drills 4 and 5 and conventional coated drills 4 and 5 ,
Work material-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / A390 plate,
Cutting speed: 180 m / min. ,
Feed: 0.2 mm / rev,
Hole depth: 16 mm,
Wet high-speed drilling test of aluminum alloy under the conditions (normal cutting speed is 90 m / min.),
About the present invention coated drills 6 and 7 and the conventional coated drills 6 and 7 ,
Work material-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / AC9B plate,
Cutting speed: 200 m / min. ,
Feed: 0.3 mm / rev,
Hole depth: 35 mm,
Wet high-speed drilling machining test of aluminum alloy under the conditions (normal cutting speed is 100 m / min.),
In each wet high-speed drilling test (using water-soluble cutting oil), the number of drilling processes 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.

Consequently the present invention the coating as the invention coated tool obtained chips 1-14, the present invention coated end mills 1-7, and the present invention cover the drill 1-7 compositional changes that constitute the hard coating layer of (Al, Cr, Si , Ti, B) The composition of the Al-Cr-Si highest content point and Ti-B highest content point of the N layer was measured by energy dispersive X-ray analysis using a transmission electron microscope. The composition was substantially the same as the Al-Cr-Si highest content point and Ti-B highest content point. Moreover, the compositionally uniform (Al, Cr, Si, Ti, B) constituting the hard coating layers of the conventional coated tips 1 to 14 , the conventional coated end mills 1 to 7 , and the conventional coated drills 1 to 7 as conventional coated tools ) When the composition of the N layer 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 has high hardness such as an Al—Si alloy and a highly reactive Al alloy work material with high heat generation. Even when used for cutting, the composition change (Al, Cr, Si, Ti, B) N layer constituting the hard coating layer as a whole has excellent high temperature hardness, oxidation resistance, high temperature strength, and heat resistance. In addition, by having excellent non-reactivity and lubricity, the reactive wear between the hard coating layer and the high-reactive work material is remarkably excellent in the lubricity with the cutting edge. Since cutting is performed in a suppressed state, the hard coating layer has a compositionally uniform (Al, Cr, Si, Ti, B) N layer while exhibiting excellent wear resistance over a long period of time. In conventional coated tools constructed with a high-speed cutting process with high heat generation, Reactive high reactivity wear of the coating layer is accelerated, and also to shortage of lubrication, 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 not only for cutting of general steel and ordinary cast iron, but also for high-speed cutting with high hardness and high heat generation of a highly reactive Al alloy. Because it exhibits excellent wear resistance over a long period of time and exhibits excellent cutting performance, it is sufficiently satisfied with the FA of cutting equipment, labor saving and energy saving of cutting work, and further cost reduction It can respond.

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 Al near the Al-Cr-Si alloy cathode electrode. -cr-Si state maximum content point is formed, a state in which TiB maximum content point is formed by (b) is TiB ₂ sintered material near the target. It is a schematic explanatory drawing of the normal arc ion plating apparatus used in forming the hard coating layer which comprises a conventional coating tool.

Claims (1)

A vapor deposition apparatus provided with a tool base made of tungsten carbide-based cemented carbide or titanium carbonitride-based cermet, an Al—Cr—Si alloy as a cathode electrode on one side, and a TiB ₂ sintered material as a target on the other side. The tool substrate is placed on a rotary table, and the tool substrate is rotated on the rotary table while arc ion plating on the Al—Cr—Si alloy cathode electrode side and sputtering on the TiB ₂ sintered material target side. In a surface-coated cutting tool in which a hard coating layer composed of a nitride layer of Al, Cr, Si, Ti, and B is formed on the surface by vapor deposition,
(A) The hard coating layer has an average layer thickness of 1 to 8 μm, and the highest Al—Cr—Si formed in the vicinity of the Al—Cr—Si alloy cathode electrode along the thickness direction of the hard coating layer. The content point and the Ti-B highest content point formed in the vicinity of the TiB ₂ sintered material target are alternately present at intervals of 0.005 to 0.1 μm,
(B) From the highest Al-Cr-Si content point to the highest Ti-B content point, from the highest Ti-B content point to the highest Al-Cr-Si content point, Al, Cr, Si, Ti, B Have a component concentration distribution structure in which the content ratio of each continuously changes,
(C) Al component, Cr component, Si component, Ti component and B component at the highest Al-Cr-Si content point formed in the vicinity of the Al-Cr-Si alloy cathode electrode are the content ratio (however, the 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 0.005 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) Al component, Cr component, Si component, Ti component, and B component at the Ti-B highest content point formed in the vicinity of the TiB2 sintered material target have their content ratios (however, the atomic ratio), respectively. When represented by X, 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. ~ 0.40, R is 0.40 to 0.55, and a composition change (Al, Cr, Si, Ti, B) N layer satisfying X + Y + Z + Q + R = 1 is formed by vapor deposition.
Surface coated cutting tool that exhibits high wear resistance with a hard coating layer in high speed cutting.

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