JP2003311508A - Surface coated cemented carbide cutting tool having hard coating layer showing excellent wear resistance under high-speed heavy cutting condition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface coated cemented carbide cutting tool having a hard coating layer showing excellent wear resistance under a high-speed heavy cutting condition. <P>SOLUTION: The surface coated cemented carbide cutting tool consists of the hard coating layer composed of composite nitride of Al, Ti and Y, and physically vapor-deposited on a surface of a tangusten carbide based cemented carbide substrate or a titanium carbonitride system cermet substrate with an overall average layer thickness of 1 to 15 μm. The hard coating layer has a component concentration distribution structure wherein the highest Al content points and the highest Ti content point exist alternately and repeatedly in a layer thickness direction at specified intervals, and wherein the contents of Al and Ti are successively changed from the highest Al containing point to the highest Ti content point, and from the highest Ti content point to the highest Al content point, respectively. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hard coating layer having excellent high-temperature hardness and heat resistance, as well as high strength and high toughness. The hard coating layer is free from chipping (small chipping) when high-speed cutting with high heat generation and heavy cutting conditions such as high cutting and high feed with high mechanical impact are performed. The present invention relates to a surface-coated cemented carbide cutting tool exhibiting excellent wear resistance (hereinafter referred to as a coated cemented carbide tool). 2. Description of the Related Art In general, a coated carbide tool is a throw-away tip which is removably attached to a tip of a cutting tool for turning or planing a work material such as steel or cast iron. Drills and miniature drills used for drilling cutting, etc., furthermore, there are solid-type end mills used for face milling and grooving where the cutting edge takes an intermittent cutting form, shoulder processing, etc. A throw-away end mill tool that is detachably attached and performs cutting in the same manner as the solid type end mill is known. [0003] Further, as a coated cemented carbide tool, a substrate made of tungsten carbide (hereinafter referred to as WC) -based cemented carbide or titanium carbonitride (hereinafter referred to as TiCN) -based cermet (hereinafter, collectively referred to as cemented carbide). On the surface of the substrate)
_{Formula: (Ti 1- (Z + X} ) Al Z Y X) N ( provided that an atomic ratio, Z is from 0.40 to .65, X is 0.005 to 0.1
Is formed by physical vapor deposition of a hard coating layer composed of a composite nitride of Ti, Al, and Y (hereinafter, referred to as (Ti, Al, Y) N) satisfying the following conditions: A cemented carbide tool has been proposed. Such a coated cemented carbide tool is characterized in that the (Ti, Al, Y) N layer constituting the hard coating layer has high-temperature characteristics (high-temperature hardness and heat resistance), and further has strength and toughness. It is also known that it is used for continuous cutting and intermittent cutting of various kinds of steel and cast iron. [0004] Further, the above coated super hard tool is prepared by charging the above super hard substrate into an arc ion plating apparatus which is a kind of physical vapor deposition apparatus schematically shown in FIG. Is heated to a temperature of, for example, 500 ° C., and an anode electrode and Ti-Al having a predetermined composition are mixed.
An arc discharge is generated between the cathode electrode (evaporation source) on which the -Y alloy is set, for example, at a current of 90 A, and a nitrogen gas is introduced as a reaction gas into the apparatus at the same time. On the other hand, under the condition that a bias voltage of, for example, -100 V is applied to the cemented carbide substrate, the surface of the cemented carbide substrate is coated with (Ti, Al,
Y) It is also known to be manufactured by depositing a hard coating layer consisting of an N layer. [0005] In recent years, the performance of cutting equipment has been remarkably improved, and on the other hand, there has been a strong demand for labor saving, energy saving, and further cost reduction for cutting. Tends to increase the speed and tends to necessitate cutting under heavy cutting conditions such as high cutting and high feed.However, in the above-mentioned conventional coated carbide tools, this is done under normal cutting conditions. There is no problem when used, but when cutting is performed at high speed and under heavy cutting conditions such as high cutting and high feed with high mechanical impact, especially the high temperature hardness and heat resistance of the hard coating layer Lack of sex,
Furthermore, since the strength and toughness are insufficient, the progress of abrasion of the hard coating layer is further promoted and chipping is liable to occur, so that at present, the service life is reached in a relatively short time. Means for Solving the Problems Accordingly, the present inventors have proposed:
In view of the above, in order to develop a coated carbide tool in which the hard coating layer exhibits excellent wear resistance especially under high-speed heavy cutting conditions, attention is paid to the hard coating layer that constitutes the conventional coated carbide tool described above. As a result of the research, (a) (Ti, Al, Y) N constituting a conventional coated carbide tool formed using the arc ion plating apparatus shown in FIG.
The layer has a substantially uniform composition throughout the thickness of the layer, and thus has a uniform high-temperature hardness and heat resistance, as well as strength and toughness. For example, FIG. b)
An arc ion plating apparatus having a structure shown in a schematic front view, that is, a rotary table for mounting a carbide substrate is provided at the center of the apparatus, and a relatively high Al content (Ti Al-T (low content)
i-Y alloy, relatively high Ti content (Al
Using an arc ion plating apparatus in which Ti-Al-Y alloy (having a low content) is opposed to each other as a cathode electrode (evaporation source), a plurality of carbide substrates are formed in a ring shape along the outer periphery of the rotary table of the apparatus. In this state, the rotating table is rotated while the atmosphere in the apparatus is a nitrogen atmosphere, and the carbide substrate itself is also rotated for the purpose of uniforming the thickness of the hard coating layer formed by vapor deposition. An arc discharge is generated between the cathode electrode (evaporation source) and the anode electrode of Al and T on the surface of the cemented carbide substrate.
When a composite nitride layer of i and Y (hereinafter, referred to as (Al-Ti, Y) N) is formed, the resulting (Al-Ti, Y) N
In the layer, the cemented carbide substrate arranged in a ring shape on the turntable is a cathode electrode of an Al—Ti—Y alloy having a relatively high Al content (low Ti content) on one side. At the point of closest approach to the source), and the cemented carbide substrate has a relatively high Ti content (low Al content) Ti-A on the other side.
At the point closest to the 1-Y alloy cathode electrode, the highest Ti content point is formed in the layer, and the rotation of the rotary table causes the highest Al content point and the highest Ti content point in the layer along the layer thickness direction. Alternately and repeatedly appear at predetermined intervals, and from the highest Al content point to the highest Ti content point, and from the highest Ti content point to the highest Al content point,
And Ti content have a component concentration distribution structure that changes continuously. (B) In the formation of the (Al-Ti, Y) N layer having the repetitive and continuously changing component concentration distribution structure of (a), Al-Ti- as the cathode electrode (evaporation source) on one side of the opposed arrangement. The Al content in the Y alloy is determined by the conventional T
The Al content in the Ti-Al-Y alloy, which is the cathode electrode (evaporation source) on the other side, is relatively higher than the Al content in the i-Al-Y alloy, and the Al content in the conventional T
The Al content of the i-Al-Y alloy is set to be relatively lower than that of the i-Al-Y alloy, and the rotation speed of the rotary table on which the carbide substrate is mounted is controlled so that the Al maximum content point is determined by the composition formula. _{: (Al 1- (M + X} ) Ti M Y X) N ( provided that an atomic ratio,
M represents 0.05 to 0.30, X represents 0.005 to 0.1), and the above-mentioned Ti maximum content point is represented by a composition formula: (Ti _{1- (N + X)}
In Al _N Y _{X) N} (provided that the atomic ratio, N is the 0.05 to 0.
35, X represents 0.005 to 0.1), and the interval between the adjacent Al maximum content point and Ti maximum content point in the thickness direction is 0.01 to 0.1 μm.
In the above Al maximum content portion, the above conventional (Al, T
i, Y) Since the Al content is relatively higher than that of the N layer, the Al content shows much higher high-temperature hardness and heat resistance (high-temperature characteristics). Al, Ti, Y) Since the Ti content is relatively higher than that of the N layer, it has higher strength and toughness,
In addition, since the interval between the highest Al content point and the highest Ti content point is extremely small, the layer as a whole has excellent high-temperature properties while maintaining high strength and high toughness. The coated cemented carbide tool composed of the (Al, Ti, Y) N layer having such a layer performs cutting of various steels and cast irons, particularly under high-speed heavy cutting conditions involving high heat generation and high mechanical impact. In such a case, the hard coating layer exhibits excellent wear resistance without chipping. The research results shown in (a) and (b) above were obtained. The present invention has been made based on the results of the above-mentioned research, and it has been proposed that (Ti, A
(1) In a coated cemented carbide tool obtained by physical vapor deposition of a hard coating layer composed of an N layer with an overall average layer thickness of 1 to 15 μm, the hard coating layer has an Al highest content point along the thickness direction. The Ti minimum content point) and the Ti maximum content point (Al minimum content point) are alternately and repeatedly present at predetermined intervals, and the Ti maximum content point and the Ti
It has a component concentration distribution structure in which the Al and Ti contents continuously change from the highest content point to the highest Al content point, and the highest Al content point has a composition formula: (Al
_{1- (M + X) Ti M} Y X) N ( provided that an atomic ratio, M 0.0
5 to .30, X represents a 0.005), the Ti maximum content point, composition _{formula: (Ti 1- (K + X} ) Al K Y X)
N (however, in terms of atomic ratio, K is 0.05 to 0.35 and X is 0.005 to 0.1), and the interval between the adjacent highest Al content points and highest Ti content points is adjacent. Is 0.0
The present invention is characterized by a coated carbide tool in which the hard coating layer exhibits excellent wear resistance under high-speed heavy cutting conditions of 1 to 0.1 μm. Next, the reason why the configuration of the hard coating layer constituting the coated carbide tool of the present invention is limited as described above will be described. (A) Composition of Al maximum content point The Al component of the Al maximum content point of the (Al-Ti, Y) N layer improves high-temperature hardness and heat resistance (high-temperature characteristics), and the Ti component improves strength and toughness. The Y component has the effect of further improving the high-temperature hardness, so that the higher the content ratio of the Al component and the Y component, the higher the high-temperature characteristics, the more suitable for high-speed cutting with high heat generation. However, when the M value indicating the ratio of Ti is less than 0.05 in the ratio (atomic ratio) to the total amount of Al and Y, the ratio of Al becomes relatively too large, and high strength and high toughness are reduced. Even if the highest Ti content points exist adjacent to each other, a decrease in the strength and toughness of the layer itself is unavoidable. As a result, chipping and the like are likely to occur, while the M value indicating the ratio of Ti is 0.30. When it exceeds, the ratio of Al relatively Too eliminated, is intended becomes impossible to ensure a desired excellent high-temperature characteristics, and X value indicating a ratio of Y is Al
If the ratio (atomic ratio) to the total amount of Ti and Ti is less than 0.005, the desired high-temperature hardness improvement effect cannot be obtained, and if the X value exceeds 0.1, the strength and toughness rapidly decrease. Therefore, the M value was set to 0.05 to 0.30, and the X value was set to 0.005 to 0.1. (B) Composition of the highest Ti content point As described above, the highest Al content point has excellent high-temperature characteristics, but is inferior in strength and toughness. To make up for the shortage,
The Ti content is high, so that the highest Ti content points, which have high strength and high toughness, are alternately interposed in the thickness direction.
0.35 in the ratio (atomic ratio) of the value to the total amount of Ti and Y
Exceeds, the proportion of Al becomes relatively too large, and it is not possible to secure desired excellent strength and toughness,
On the other hand, when the K value is also less than 0.05, the relative T
Since the ratio of i becomes too large, it becomes impossible to provide a desired high-temperature characteristic to the highest Ti content point.
The value was determined to be 0.05 to 0.35, and the X value indicating the ratio of the Y component was determined to be 0.005 to 0.1 for the same reason as in the above Al maximum content point. (C) Interval between the highest Al content point and the highest Ti content point If the interval is less than 0.01 μm, it is difficult to clearly form each point with the above composition, and as a result, the desired High strength and high toughness, and excellent high-temperature properties cannot be secured, and the interval is 0.1 μm.
If it exceeds m, the disadvantages of the respective points, that is, insufficient strength and toughness at the highest Al content point, and insufficient high-temperature characteristics at the highest Ti content point appear locally in the layer, which causes chipping on the cutting edge. Is more likely to occur and the progress of wear is promoted.
０．１0.1 μm. (D) Overall average thickness of the hard coating layer If the thickness is less than 1 μm, the desired wear resistance cannot be ensured. On the other hand, if the average thickness exceeds 15 μm, chipping occurs. The average layer thickness was determined to be 1 to 15 μm because it was easier. Next, the coated carbide tool of the present invention will be described in detail with reference to examples. (Example 1) As raw material powders, WC powder, TiC powder, VC powder, and Ta each having an average particle size of 1 to 3 µm
C powder, NbC powder, Cr ₃ C ₂ powder, and Co powder were prepared, and these raw material powders were blended in the composition shown in Table 1, wet-mixed in a ball mill for 72 hours, dried, and then dried under a pressure of 100 MPa. Is pressed into a green compact, and this green compact is sintered in a vacuum of 6 Pa at a temperature of 1400 ° C. for 1 hour, and after sintering, R: 0.03
Honing process, ISO standard, CNMG120
WC-based cemented carbide substrates A1 to A10 having a chip shape of 408 were formed. Further, as raw material powders,
TiCN having an average particle size of 2 μm (by weight ratio TiC /
(TiN = 50/50) powder, Mo ₂ C powder, ZrC powder, NbC powder, TaC powder, WC powder, Co powder, and Ni powder were prepared, and these raw material powders were blended into the composition shown in Table 2. After wet-mixing with a ball mill for 24 hours and drying, the mixture is pressed into a green compact at a pressure of 100 MPa, and the green compact is heated in a nitrogen atmosphere of 2 kPa at a temperature of:
Sintered under the condition of holding at 1500 ° C. for 1 hour, and after sintering, the cutting edge portion is subjected to a honing process of R: 0.03 to obtain a TiC having a chip shape conforming to ISO standard, CNMG120408.
Carbide substrates B1 to B6 made of N-based cermet were formed. Next, each of the above-mentioned super-hard substrates A1 to A10 and B1 to B6 is ultrasonically washed in acetone and dried, and placed on a rotary table in an arc ion plating apparatus shown in FIG. Attached along the outer periphery, one side cathode electrode (evaporation source) Ti-Al-Y for forming the highest Ti content point having various component compositions
Alloy, Al-Ti-Y for forming the highest Al content point having various component compositions as the cathode electrode (evaporation source) on the other side
The alloy was placed facing the rotary table, and metal Ti for bombarding was also installed. First, the inside of the apparatus was evacuated and heated to 500 ° C. with a heater while maintaining the vacuum at 0.5 Pa or less. After that, a DC bias voltage of -1000 V is applied to the super-hard substrate rotating while rotating on the rotary table, and a current of 100 A flows between the metal Ti of the cathode electrode and the anode electrode to cause arc discharge. Then, the surface of the cemented carbide substrate is cleaned by Ti bombarding. Then, nitrogen gas is introduced into the apparatus as a reaction gas to make a reaction atmosphere of 2 Pa, and the cemented carbide substrate rotating while rotating on the rotary table. 100V DC bias voltage is applied and each cathode electrode
A current of 100 A is passed between the (Ti-Al-Y alloy for forming the highest Ti content point and the Al-Ti-Y alloy for forming the highest Al content point) and the anode electrode to generate an arc discharge. On the surface of the hard substrate, Al maximum content points and Ti maximum content points of the target compositions shown in Tables 3 and 4 are alternately and repeatedly present at the target intervals shown in Tables 3 and 4 along the layer thickness direction, And from the highest Al content, the T
i has a component concentration distribution structure in which the Al and Ti contents continuously change from the highest content point to the highest Ti content point to the highest Al content point, and the target total layer thickness also shown in Tables 3 and 4. By depositing a hard coating layer of
Inventive surface-coated cemented carbide throw-away tips (hereinafter referred to as the present invention-coated cemented carbide tips) 1 to 16 as inventive-coated cemented carbide tools were produced, respectively. For the purpose of comparison, these super-hard substrates A1
A10 and B1 to B6 were ultrasonically cleaned in acetone, dried, and charged into a usual arc ion plating apparatus shown in FIG. 2 to obtain various component compositions as cathode electrodes (evaporation sources). Ti-Al- with
After mounting the Y alloy and further mounting the Ti metal for bombarding, first heating the inside of the apparatus to 500 ° C. with a heater while evacuating the inside of the apparatus to maintain a vacuum of 0.5 Pa or less, A DC bias voltage of -1000 V is applied to the substrate, and a current of 100 A flows between the metal Ti of the cathode electrode and the anode electrode to generate an arc discharge, thereby cleaning the surface of the super hard substrate by Ti bombarding. Nitrogen gas was introduced into the apparatus as a reaction gas to make a reaction atmosphere of 2 Pa, and a DC bias voltage of -100 V was applied to the cemented carbide substrate.
A current of 100 A is caused to flow between the Y alloy and the anode electrode to generate an arc discharge, whereby the cemented carbide substrates A1 to A
(Ti, Al, Y) N having the target composition and the target layer thickness shown in Tables 5 and 6 and having substantially no composition change along the layer thickness direction on each surface of B10 and B1 to B6.
By depositing a hard coating layer composed of layers, a conventional surface coated cemented carbide throw-away tip as a conventionally coated cemented carbide tool (hereinafter referred to as a conventionally coated cemented carbide tip) 1 to 16
Was manufactured respectively. Next, the coated carbide tips 1 to 1 according to the present invention will be described.
No. 6 and conventional coated carbide tips 1 to 16 were screwed to the tip of a tool steel tool with a fixing jig. Work material: JIS SCM440 round bar, Cutting speed: 350 m / min . Infeed: 4 mm Feed: 0.3 mm / rev. , Cutting time: 5 minutes, Dry continuous high-speed, high-cut cutting test of alloy steel under the following conditions: Work material: JIS S45C, longitudinally spaced round bar with four longitudinal grooves, Cutting speed: 350 m / min . Infeed: 2.5 mm Feed: 0.5 mm / rev. , Cutting time: 10 minutes, Dry intermittent high-speed high-feed cutting test of carbon steel under the following conditions:
Work material: JIS FC300 round bar, Cutting speed: 350 m / min. Infeed: 4 mm Feed: 0.35 mm / rev. A dry continuous high-speed high-cut cutting test of cast iron was performed under the following conditions: cutting time: 5 minutes, and the flank wear width of the cutting edge was measured in each cutting test. Table 7 shows the measurement results. [Table 1] [Table 2] [Table 3] [Table 4] [Table 5] [Table 6] [Table 7] (Example 2) As raw material powder, average particle size:
Medium coarse WC powder having 5.5 μm, fine WC powder of 0.8 μm, TaC powder of 1.3 μm, 1.2 μm
NbC powder, 1.2 μm ZrC powder, 2.3 μm
m Cr ₃ C ₂ powder, 1.5 μm VC powder, 1.0 μm
μm of (Ti, W) C powder and 1.8 μm of Co
Powders were prepared, and each of these raw material powders was blended into the blending composition shown in Table 8, further added with wax, and ball-mixed in acetone for 24 hours, and dried under reduced pressure.
It is press-molded into various compacts of a predetermined shape at a pressure of 0 MPa, and these compacts are compacted in a vacuum atmosphere of 6 Pa at 7 ° C. /
The temperature is raised to a predetermined temperature in the range of 1370 to 1470 ° C. at a heating rate of 1 minute, held at this temperature for 1 hour, and then sintered under the condition of furnace cooling to obtain a 3 mm diameter of 8 mm, 13 mm, and 26 mm. Kinds of round bar sintered bodies for forming a cemented carbide substrate are formed, and the above three kinds of round bar sintered bodies are subjected to grinding processing in a combination shown in Table 8 to obtain a diameter x length of a cutting edge portion. Is 6mm × 1 each
3mm, 10mm x 22mm, and 20mm x 45m
Carbide substrate (end mill) C-1 having a dimension of m and having a four-flute square shape with a twist angle of 30 degrees.
To C-8 were each manufactured. Next, these super-hard substrates (end mills)
C-1 to C-8 were ultrasonically cleaned in acetone, dried, and charged into the arc ion plating apparatus shown in FIG. 1 under the same conditions as in Example 1 above. Along the direction, the highest Al content point and the highest Ti content point of the target composition shown in Table 9 are alternately repeated at the same target intervals as shown in Table 9, and from the highest Al content point to the highest Ti content point. From the highest Ti content point to the Al
By depositing a hard coating layer having a target total layer thickness as shown in Table 9 having a component concentration distribution structure in which the Al and Ti contents continuously change to the highest content point, End mills made of the surface-coated cemented carbide of the present invention as tools (hereinafter, referred to as the coated carbide end mills of the present invention) 1 to 8 were produced. For the purpose of comparison, the above-mentioned ultra-hard substrates (end mills) C-1 to C-8 were ultrasonically cleaned in acetone, dried, and then dried in a usual arc ion ion shown in FIG. It was charged into a plating apparatus, and had the target composition and the target layer thickness shown in Table 10 under the same conditions as in Example 1, and had substantially no composition change along the layer thickness direction (Ti, By depositing a hard coating layer consisting of an Al, Y) N layer, end mills made of conventional surface-coated cemented carbide as conventional coated carbide tools (hereinafter, referred to as conventional coated carbide end mills) 1 to 8 were manufactured, respectively. . Next, the coated carbide end mill 1 of the present invention will be described.
-8 and the conventional coated carbide end mills 1-8, the coated carbide end mills 1-3 of the present invention and the conventional coated carbide end mills 1-3 are: work material: plane dimension: 100 mm × 250 mm, thickness: 5
0 mm JIS SKD11 plate material, Cutting speed: 120 m / min. , Groove depth (cut): 6 mm, Table feed: 770 mm / min, Dry high-speed high feed groove cutting test of tool steel, coated carbide end mills 4 to 6 of the present invention and coated coated carbide end mills 4 to About 6, work material: plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS SUS304 plate, Cutting speed: 120 m / min. , Groove depth (cut): 15 mm, Table feed: 460 mm / min, Dry high-speed high-cut groove cutting test of stainless steel under the following conditions: coated carbide end mills 7, 8 according to the present invention and conventional coated carbide end mills 7, For No. 8, Work material: Plane dimensions: 100 mm × 250 mm, thickness: 5
0 mm JIS SNCM439 plate material, Cutting speed: 150 m / min. , Groove depth (cut): 10 mm, Table feed: 380 mm / min, Dry high-speed high-feed groove cutting test of alloy steel was performed under the following conditions. 0.1mm where flank wear width is used as a guide to service life
The cutting groove length up to was measured. The measurement results are shown in Tables 9 and 10, respectively. [Table 8] [Table 9] [Table 10] Example 3 The diameter produced in Example 2 was 8 mm (for forming the cemented carbide substrates C-1 to C-3) and 13 m.
m (for forming the carbide substrate C-4 to C-6), and 26 mm
Using three types of round bar sintered bodies (for forming the cemented carbide substrates C-7 and C-8), the three types of round bar sintered bodies were subjected to grinding to obtain a diameter x length of a groove forming portion. Are 4 mm x 13 mm (carbide substrate D-1 to D-3) and 8 mm x 22 mm (carbide substrate D
-4 to D-6), and a carbide substrate having dimensions of 16 mm × 45 mm (carbide substrates D-7 and D-8) and having a two-blade shape with a twist angle of 30 degrees ( Drill) D
-1 to D-8 were produced respectively. Next, these carbide substrates (drills) D-
The cutting blades Nos. 1 to D-8 were honed, ultrasonically cleaned in acetone, dried, and charged in an arc ion plating apparatus also shown in FIG. Under the conditions, the Al maximum content point and the Ti maximum content point of the target composition shown in Table 11 alternately and repeatedly along the layer thickness direction at the target interval shown in Table 11, and from the Al maximum content point. The highest Ti content point, the T
from the highest content point to the highest content point of Al
The surface coating of the present invention as a coated carbide tool according to the present invention is obtained by depositing a hard coating layer having a component concentration distribution structure in which the content continuously changes and having the target total layer thickness also shown in Table 11. Drills made of cemented carbide (hereinafter referred to as coated carbide drills of the present invention) 1 to 8 were produced, respectively. For the purpose of comparison, the cutting edges of the above-mentioned carbide substrates (drills) D-1 to D-8 were honed, ultrasonically washed in acetone, and dried, and then, as shown in FIG.
And having the target composition and the target layer thickness shown in Table 12 under the same conditions as in Example 1 above, and substantially along the layer thickness direction. By depositing a hard coating layer composed of a (Ti, Al, Y) N layer having no change in composition, a drill made of a conventional surface-coated cemented carbide as a conventionally coated carbide tool (hereinafter referred to as a conventional coated carbide drill) 1 to 8 were manufactured respectively. Next, the coated carbide drills of the present invention 1 to 8
Of the coated carbide drills 1 to 8 of the present invention, the coated carbide drills 1 to 3 of the present invention and the coated carbide drills 1 to 3 of the present invention are: work material: plane dimension: 100 mm × 250 mm, thickness: 5
0 mm JIS SKD61 plate material, Cutting speed: 60 m / min. , Feed: 0.20 mm / rev, Hole Depth: 12 mm Wet high-speed high feed drilling cutting test of tool steel, coated carbide drills 4 to 6 according to the present invention and conventional coated carbide drills 4 to 6 , Work material: Plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS FCD400 plate, Cutting speed: 80 m / min. , Feed: 0.35mm / rev, Hole Depth: 24mm Wet high-speed high-feed drilling test of ductile cast iron, coated carbide drills 7, 8 of the present invention and conventional coated carbide drills 7, 8 , Work material: Plane dimensions: 100 mm x 250 mm, thickness: 5
JIS FC300 plate material of 0 mm, Cutting speed: 90 m / min. , Feed: 0.40 mm / rev, Hole depth: 50 mm Wet high-speed high-feed drilling test of cast iron under the following conditions:
The flank wear width of the cutting edge of the tip was 0.1 mm in all wet drilling tests (using water-soluble cutting oil).
The number of drilling processes up to 3 mm was measured. The measurement results are shown in Tables 11 and 12, respectively. [Table 11] [Table 12] The hard steels constituting the coated carbide tips 1-16, coated carbide end mills 1-8, and coated drills 1-8 of the present invention as the coated carbide tools of the present invention obtained as a result. The composition of the highest Al content point and highest Ti content point in the coating layer, as well as the conventional coated carbide tips 1 to 16 as conventional coated carbide tools and the conventional coated carbide end mills 1 to
8 and the hard coating layers of the conventional coated carbide drills 1 to 8 were measured using an Auger spectroscopic analyzer, and each showed substantially the same composition as the target composition. Further, the interval between the highest Al content point and the highest Ti content point in the hard coating layer of these coated carbide tools of the present invention, and the total layer thickness thereof, and the thickness of the hard coating layer of the conventional coated carbide tool,
When the cross section was measured using a scanning electron microscope, all the values showed substantially the same value as the target value. From the results shown in Tables 3 to 12, it can be seen from the results shown in Tables 3 to 12 that the hard coating layer has, in the thickness direction, the highest Al content point having excellent high-temperature hardness and heat resistance, and Ti having high strength and high toughness. And the highest content point alternately and repeatedly at predetermined intervals, and the highest Al content point and the highest Ti content point,
The coated carbide tool of the present invention having a component concentration distribution structure in which the Al and Ti contents continuously change from the highest content point to the highest Al content point, respectively, is capable of cutting various kinds of steel and cast iron at a high temperature. Even when performed under high cutting conditions and high cutting conditions such as high cutting and high feed with high mechanical impact, the hard coating layer exhibits excellent wear resistance without chipping. On the other hand, the hard coating layer has substantially no composition change along the layer thickness direction (Ti,
In a conventional coated carbide tool comprising an Al, Y) N layer,
Under the high-speed heavy cutting conditions, the hard coating layer has insufficient high-temperature properties, and insufficient strength and toughness. Is evident. As described above, the coated cemented carbide tool of the present invention can be used not only for cutting under ordinary conditions, but also for cutting various kinds of steel and cast iron, etc., at high speed heavy cutting accompanied by high heat generation and high mechanical impact. Even when performed under the conditions, since excellent abrasion resistance is exhibited without occurrence of chipping, labor saving and energy saving of cutting work, and further, cost reduction can be sufficiently satisfied.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an arc ion plating apparatus used to form a hard coating layer constituting a coated carbide tool of the present invention, (a) is a schematic plan view, (b) Is a schematic front view. FIG. 2 is a schematic explanatory view of a conventional arc ion plating apparatus used for forming a hard coating layer constituting a conventional coated carbide tool.

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Takashi Fujisawa             1511 Furamagi, Ishishita-cho, Yuki-gun, Ibaraki Prefecture             Mitsubishi Materials Corporation Tsukuba Works (72) Inventor Kazuki Izumi             1511 Furamagi, Ishishita-cho, Yuki-gun, Ibaraki Prefecture             Mitsubishi Materials Corporation Tsukuba Works (72) Inventor Hidemitsu Takaoka             1002-14 Mukoyama, Naka-machi, Naka-gun, Ibaraki             Terial Co., Ltd.             Inside F-term (reference) 3C037 CC01 CC04 CC09 CC11                 3C046 FF03 FF05 FF10 FF19 FF25                 4K029 AA02 BA58 BC02 BD05 CA03

Claims (1)

Claims: 1. A hard coating layer made of a composite nitride layer of Al, Ti and Y on a surface of a tungsten carbide-based cemented carbide substrate or a titanium carbonitride-based cermet substrate having a total thickness of 1 to 15 μm. In a surface-coated cemented carbide cutting tool formed by physical vapor deposition with an average layer thickness, the hard coating layer alternates at a predetermined interval between the highest Al content point and the highest Ti content point along the thickness direction. From the highest Al content to the highest Ti content, from the highest Ti content to the highest Al content,
And the content of Ti has a component concentration distribution structure in which each of the components continuously changes.
_{1- (M + X) Ti M} Y X) N ( provided that an atomic ratio, M 0.0
5 to .30, X represents a 0.005), the Ti maximum content point, composition _{formula: (Ti 1- (K + X} ) Al K Y
_X ) N (where K is 0.05 to 0.35 in atomic ratio,
X represents 0.005 to 0.1), and the interval between the adjacent Al maximum content points and adjacent Ti maximum content points is
A surface-coated cemented carbide cutting tool in which the hard coating layer exhibits excellent wear resistance under high-speed heavy cutting conditions, characterized in that the cutting tool has a thickness of 0.01 to 0.1 µm.