JP2001239404A - Cutting tool made of surface coated cemented carbide having good chipping resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting too made of surface coated cemented carbide alloy having good chipping resistance. SOLUTION: The cutting tool made of surface coated cemented carbide alloy with average layer thickness of 3-30 μm is formed by chemical deposition and/or physical deposition of a Ti compound layer comprising one or two of a TiC layer, a TiN layer, a TiCN layer, a TiCO layer, and a TiCNO layer, and a hard coated layer made of an Al2O3 layer. In addition to the hard coated layer, using a Ti oxide layer that has an average layer thickness of 0.1-3 μm and satisfies an atomic ratio 1.2-1.7 for X:Ti for composition formula: TiOX as the most lowest surface layer and a Ti nitrogen oxide layer that has an average layer thickness of 0.05-2 μm and satisfies an atomic ratio 0.01-0.4 for Y:Ti for composition formula: TiN1-Y(O)Y (where (O) is oxygen diffused from the most lowest surface layer) as the most highest surface layer, chemical deposition and/or physical deposition as hard coated layer is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a surface-coated cemented carbide cutting tool (hereinafter referred to as a cutting tool) in which a hard coating layer exhibits excellent chipping resistance, particularly when used for high-speed cutting of various steels and cast irons. , Coated carbide tools).

[0002]

2. Description of the Related Art Generally, cutting tools include a throw-away tip which is detachably attached to a tip of a cutting tool for turning or planing of various materials such as steel and cast iron. Drills and miniature drills used for drilling and cutting of solids, and solid type end mills used for face milling and grooving of the work material, shoulder machining, and the like, and the detachable tip is detachably attached. In addition, a throw-away end mill tool or the like that performs cutting in the same manner as the solid type end mill is known. Further, conventionally, generally, as the above-mentioned cutting tool, a tungsten carbide-based cemented carbide substrate (hereinafter, referred to as
A carbide of Ti (hereinafter referred to as Ti)
C) layer, nitride (hereinafter also indicated by TiN)
, A carbonitride (hereinafter, referred to as TiCN) layer, a carbon oxide (hereinafter, referred to as TiCO) layer, and a Ti or a carbonitride (hereinafter, referred to as TiCNO) layer. A compound layer and aluminum oxide (hereinafter referred to as A
3~30μ a hard layer composed of a l ₂ O indicated by ₃₎ layer
Coated carbide tools made by chemical and / or physical vapor deposition with an average layer thickness of m are known. In the above-mentioned conventional coated carbide tool, the TiN layer of the Ti compound layer constituting the hard coating layer itself has a golden surface tone, so that it is easy to distinguish before and after use of the tool. In order to achieve this, it is also known that the outermost surface layer of the hard coating layer is composed of a TiN layer.

In general, the Ti compound layer and the Al ₂ O ₃ layer constituting the hard coating layer of the coated carbide tool have a granular crystal structure, and the Al ₂ O ₃ layer has an α-type crystal structure. The Al ₂ O ₃ layer is subjected to X-ray diffraction using, for example, a Cukα ray having a wavelength of 1.5 angstroms as a radiation source. Is carried out, if the layer is an α-Al ₂ O ₃ layer, depending on the conditions for forming the layer, both are 2θ and 2
5.6 degrees (012 crystal plane orientation), 35.1 degrees (104 crystal plane orientation), 37.8 degrees (110 crystal plane orientation), 43.
4 degrees (113 crystal plane orientation), 52.6 degrees (024 crystal plane orientation), 57.5 degrees (116 crystal plane orientation), 66.5 degrees (124 crystal plane orientation), and 68.2 degrees (030 crystal plane). Α-Al ₂ O ₃ layer showing an X-ray diffraction pattern in which the highest diffraction peak height appears at any diffraction angle of (plane orientation), and κ-Al ₂ O ₃ layer In the same manner, depending on the formation conditions, 19.7 is 29.7.
Degrees, 29.4 degrees, 32.1 degrees, 34.9 degrees, 37.3 degrees
Κ-, which shows an X-ray diffraction pattern in which the highest diffraction peak height appears at any of the diffraction angles of degrees, 43.9 degrees, 52.6 degrees, 56.0 degrees, 62.3 degrees, and 65.2 degrees. Al ₂
It is also well known that an O ₃ layer can be formed.

Further, as described in, for example, JP-A-6-8010 and JP-A-7-328808, the TiCN layer of the Ti compound layer constituting the hard coating layer of the coated carbide tool is For the purpose of improving the toughness of the layer itself, it is formed by chemical vapor deposition at a medium temperature range of 700 to 950 ° C. using a mixed gas containing an organic carbonitride as a reaction gas in a normal chemical vapor deposition apparatus. It is also known to have a growing crystal structure.

[0005]

On the other hand, in recent years, there has been a strong demand for labor saving and energy saving for cutting work, and with this, cutting work tends to be accelerated. In particular, when the outermost layer of the hard coating layer is a TiN layer formed by vapor deposition for the purpose of identification before and after use, the TiN layer has a particularly high adhesiveness to various types of steel as a work material. In high-speed cutting with heat generation, the above-mentioned Ti
Strongly adheres to the N layer and acts to locally peel off the TiN layer from the hard coating layer.
Since the N layer has excellent adhesion to both the other constituent layers, the Ti compound layer and the Al ₂ O ₃ layer, these constituent layers are also locally peeled off together with the TiN layer. As a result, chipping (small chipping) occurs at the cutting edge, and the service life is currently reached in a relatively short time.

[0006]

Means for Solving the Problems Accordingly, the present inventors have
In view of the above, attention has been paid to a conventional coated carbide tool in which the outermost surface layer of the hard coating layer is formed of a TiN layer, and in particular, to improve chipping resistance under high-speed cutting conditions. As a result of the research, on the surface of the conventional coated carbide tool, first, as the outermost surface underlayer, the reaction gas composition was
By _{volume%, TiCl 4: 0.2~10%,} CO 2: 0.1~10%, Ar: 5~60%, H 2: remainder, and then, and, Temperature of reaction atmosphere: 800 to 1100 ° C., the reaction Atmospheric pressure: 4 to 70 kPa (30 to 525 torr)
r) under the following conditions, an average layer thickness of 0.1 to 3 μm, and the ratio of oxygen to Ti is 1.25 to 1.90 in atomic ratio, as measured by an Auger spectrometer, that is, In the case of the composition formula: TiO _W , a Ti oxide layer satisfying an atomic ratio of W: Ti to 1.25 to 1.90 is formed, and a top surface layer is formed on the Ti oxide layer. as, under normal conditions, i.e., the reaction gas composition, by _{volume%, TiCl 4: 0.2~10%,} N 2: 4~60%, H 2: remainder, and then, and, temperature of reaction atmosphere: 800 1100 ° C., reaction atmosphere pressure: 4 to 90 kPa (30 to 675 torr)
r) T having an average layer thickness of 0.05 to 2 μm under the following conditions:
When the iN layer is formed, oxygen of the Ti oxide layer constituting the outermost surface underlayer diffuses when the outermost surface layer is formed, and T
An i-nitride oxide layer is formed.
The outermost surface underlayer after the formation of the i-nitrogen oxide layer was measured by an Auger spectrometer at the center in the thickness direction, and the oxygen content was
When represented by the atomic ratio of 1.2 to 1.7, that is, the composition formula: TiO _x , the Ti oxide layer satisfies the following: 1.2 to 1.7 of the atomic ratio to X: Ti. The outermost layer,
Similarly, the central part in the thickness direction is measured by an Auger spectrometer, and the ratio of the diffused oxygen is 0.01 to
0.4, that is, when represented by the composition formula: TiN _1-Y (O) _Y , (where (O) indicates oxygen diffused from the outermost underlayer), the atomic ratio of Y to Ti is 0. .01 to 0.4, and a Ti nitride oxide layer satisfying
In a coated carbide tool in which a nitrided oxide layer and a Ti oxide layer are chemically and / or physically deposited as the outermost surface layer and the outermost surface underlayer of the hard coating layer, particularly, the Ti nitrided oxide layer is composed of the TiN High-speed cutting with high heat generation because it has the same golden surface tone as the layer, so that it can be identified before and after the use of the tool, and it has extremely low adhesion to various steels as the work material. In addition, since the chips heated at a high temperature are not adhered to, the generation of chipping of the cutting edge is significantly suppressed, and the research result that excellent cutting performance is exhibited over a long period of time was obtained. .

The present invention has been made on the basis of the above research results, and a TiC layer, T
a Ti compound layer composed of one or more of an iN layer, a TiCN layer, a TiCO layer, and a TiCNO layer;
The hard coating layer consisting of the Al ₂ O ₃ layer with an average layer thickness of 3~30μm in chemical vapor deposition and / or physical vapor deposition coated cemented carbide comprising, in addition to the above hard layer further outermost underlayer Has an average layer thickness of 0.1 to 3 μm,
In addition, when represented by the composition formula: TiO _x , a Ti oxide layer that satisfies the following formula: X: atomic ratio to Ti: 1.2 to 1.7 measured by Auger spectroscopy at the center in the thickness direction. And, as the outermost layer,
When it has an average layer thickness of 0.05 to 2 μm and is represented by the composition formula: TiN _1-Y (O) _Y , where (O) indicates oxygen diffused from the outermost underlayer. Similarly, a central portion in the thickness direction is measured by an Auger spectroscopic analyzer, and a Ti oxynitride layer satisfying 0.01 to 0.4 as an atomic ratio with respect to Y: Ti is used as a hard coating layer by chemical vapor deposition and / or Alternatively, it is characterized by a coated carbide tool having excellent chipping resistance, which is obtained by physical vapor deposition.

[0008] In the coated carbide tool of the present invention,
The diffusion oxygen ratio (Y value) of the Ti nitride layer constituting the outermost surface layer of the hard coating layer is 0.01 to
The reason for setting the value to 0.40 is that if the value is less than 0.01, the desired effect in suppressing the adhesion to the chips cannot be secured, while if the value exceeds 0.40, pores are formed in the layer. This is because they are easily formed, and it is difficult to stably form a sound outermost surface layer.

Further, as described above, the Ti nitride oxide layer also constituting the outermost surface layer first serves as an outermost surface underlayer so that the oxygen ratio is 1.25 to 1.90 in atomic ratio to Ti.
(W value) is formed by forming a Ti oxide layer and then depositing a TiN layer on the outermost surface underlayer under ordinary conditions. Diffusion of oxygen from the surface underlayer is indispensable, but if the W value of the Ti oxide layer constituting the outermost surface underlayer is less than 1.25, the diffusion reaction of oxygen into the TiN layer rapidly increases. When the W value exceeds 1.90, the ratio (Y value) of the diffused oxygen in the outermost surface layer cannot be increased to 0.01 or more in atomic ratio with respect to Ti.
Since the atomic ratio of diffused oxygen in the outermost surface layer exceeds 0.40 in atomic ratio to Ti, W
The value is defined as 1.25 to 1.90. In this case, the ratio of oxygen (X
Value) takes on a value within the range of 1.2 to 1.7 in atomic ratio to Ti. In other words, the X value of the outermost surface underlayer after the outermost surface layer is formed is 1.2 to 1.7. If you are satisfied,
The Y value of the outermost surface layer satisfies 0.01 to 0.40.

Further, the average layer thickness of each of the outermost surface layer and the outermost underlayer constituting the hard coating layer is set to 0.0
When the average layer thickness is less than 0.05 μm or less than 0.1 μm, the desired surface color (golden color) cannot be secured in the former case. In the latter, the supply of oxygen to the outermost surface layer becomes insufficient, while the former provides a color tone providing effect of 2 μm and the latter provides an oxygen supplying effect of 3 μm with an average layer thickness of sufficiently satisfactory. It is based on The reason why the average thickness of the hard coating layer is set to 3 to 30 μm is that if the thickness is 3 μm, it is not possible to secure the desired excellent wear resistance. This is because chipping and chipping easily occur in the blade.

Further, the Ti oxide layer as the outermost surface underlayer is formed on the surface of the Al ₂ O ₃ layer constituting the hard coating layer, and has a W value in the range of 1.25 to 1.90. Condition on the lower side of, for example, in the range of 1.25 to 1.50,
When formed on the thin side having an average layer thickness in the range of 0.1 to 3 μm, for example, in the range of 0.1 to 1 μm, sufficient interlayer adhesion between the Al ₂ O ₃ layer and the Al ₂ O ₃ layer is obtained. In some cases, depending on the conditions for forming the Ti oxide layer, sufficient interlayer adhesion may be obtained even in this case. Therefore, in this case, after forming the Ti oxide layer, , the atmosphere of the following, namely, the atmospheric gas composition, TiCl _4: 0.05 to 10% by volume, the inert gas: the rest, and then, and ambient temperature: 800 to 1100 ° C., atmospheric pressure: 4~90kPa (30~ 675Torr
r) for a predetermined period of time, for example, about 5 minutes to 5 hours, in the atmosphere defined by the following equation, at the interface between the Ti oxide layer and the Al ₂ O ₃ layer,
Preferably, an interdiffusion layer is formed with an average layer thickness of 0.05 to 2 μm to improve interlayer adhesion, and furthermore, to improve interlayer adhesion between the Ti oxide layer and the Al ₂ O ₃ layer. The treatment may be performed for the purpose of further improving interlayer adhesion even when the W value and the average layer thickness of the Ti oxide layer are values other than the values on the low side and the thin side. .

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a coated carbide tool of the present invention
Will be specifically described with reference to examples. (Example 1) As raw material powders, each was 0.5 to 4 μm.
WC powder having a predetermined average particle size in the range of (Ti,
W) C (weight ratio, hereinafter the same, TiC / WC = 30/7)
0) powder, (Ti, W) CN (TiC / TiN / WC =
24/20/56) powder, (Ta, Nb) C (TaC /
NbC = 90/10) powder, Cr_ThreeC_TwoPowder, and Co
Powders are prepared, and these raw material powders are mixed as shown in Table 1.
And wet mixed in a ball mill for 72 hours, dried
9.8 × 10⁷Pa (1 ton / cm^Two) At pressure
It is pressed into a green compact of a predetermined shape, and this green compact is 1.3
Pa (1 × 10 ^-21300 to 15 in a torr) vacuum
Vacuum firing at a predetermined temperature within the range of 00 ° C for 1 hour
Stipulated in ISO / CNMG120408
Carbide substrate (chip)
P) A to F were manufactured respectively.

Next, these super-hard substrates (chips) A to F
Table 2 and Table 3 (l-TiCN in Table 2 is a TiCN having a vertically-grown crystal structure described in JP-A-6-8010) using a conventional chemical vapor deposition apparatus with the surface of The table shows the conditions for forming the layer, and the others indicate the conditions for forming a normal granular crystal structure, and the “target diffraction angles” of α-Al ₂ O ₃ and κ-Al ₂ O ₃ in Table 2. Indicates the target diffraction angle (2θ) at which the highest diffraction peak height appears in the X-ray diffraction pattern) under the conditions shown in Tables 4 and 5. By forming a hard coating layer composed of an Al ₂ O ₃ layer, an outermost surface layer composed of a diffused oxygen-containing Ti oxynitride layer and an outermost surface underlying layer composed of a diffused oxygen supply Ti oxide layer, FIG. (A) is a schematic perspective view, and (b) is a schematic longitudinal section. In shown by the present invention a surface coating made of cemented carbide indexable as the present invention coated carbide tool having a shape (hereinafter, referred to as the present invention coated carbide inserts) 1
Under the same conditions except that a TiN layer is formed instead of the outermost surface layer and the outermost surface underlayer as the outermost surface layer. Way chips (hereinafter, referred to as conventional coated carbide chips) 1 to 10 were manufactured, respectively.

Further, the above-mentioned coated carbide tips 1 to 1 according to the present invention are provided.
In the former case, the atmosphere gas composition was changed to TiCl after the formation of the Ti oxide layer as the outermost surface underlayer.
₄ : 0.5% by volume, Ar: remaining, ambient temperature 10
00 ° C. and atmospheric pressure of 13.3 kPa (100 Torr)
r), the atmosphere gas composition was changed to TiCl ₄ : 0.1% by volume, A
r: Remaining and actively interacting with the interface between the Al ₂ O ₃ layer and the Ti oxide layer under the condition of maintaining the atmosphere temperature at 1000 ° C. and the atmosphere pressure at 6.7 kPa (50 Torr) for 2 hours. An interlayer adhesion improving treatment for forming a diffusion layer was performed. As a result, in the cross-sectional measurement using a scanning electron microscope and an Auger spectrometer, the average layer thickness (average of 5 points) of the interface between the Al ₂ O ₃ layer and the Ti oxide layer was 0.5 in the coated carbide tip 3 of the present invention. The formation of an interdiffusion layer of 6 μm and 0.8 μm in average thickness (average of 5 points) was also observed in the coated superhard tip 7 of the present invention. The oxygen content ratio (Y value and X value) of the center part in the thickness direction of the outermost surface layer and the outermost surface underlayer constituting the hard coating layers of the coated ultra-hard chips 1 to 10 of the present invention obtained as a result. Was measured using an Auger spectrometer, and the values shown in Table 6 were shown. Further, regarding the α-Al ₂ O ₃ layer and the κ-Al ₂ O ₃ layer constituting the hard coating layers of the above-mentioned coated carbide tips 1 to 10 of the present invention and the conventionally coated carbide tips 1 to 10,
When observed by X-ray diffraction using a Cukα ray having a wavelength of 5 angstroms as a radiation source, an X-ray diffraction pattern in which the highest diffraction peak height appears at substantially the same diffraction angle as the target diffraction angle (2θ) was obtained. , And each of them has a golden surface tone, and the layer thicknesses of the constituent layers constituting the hard coating layer were measured in cross section using a scanning electron microscope. The average layer thickness (5 point average) was shown. The relationship between the target value and the actually measured value showed the same result in Examples 2 and 3 below.

Next, the coated carbide tips 1 to 1 according to the present invention will be described.
0 and the conventional coated carbide tips 1 to 10 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: 1.5 mm Feed: 0.2 mm / rev. , Cutting time: 5 minutes, Dry high-speed continuous turning test of alloy steel under the following conditions: Work material: JIS SNCM 439 Round bar with four longitudinal grooves at regular intervals in the longitudinal direction, Cutting speed: 300 m / min . Infeed: 1.5 mm Feed: 0.25 mm / rev. , Cutting time: 5 minutes, Dry high-speed intermittent turning test of alloy steel under the conditions of
In each turning test, the flank wear width of the cutting edge was measured. Table 6 shows the measurement results.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

[Table 3]

[0019]

[Table 4]

[0020]

[Table 5]

[0021]

[Table 6]

(Example 2) As the raw material powder, the average particle size was as follows:
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 (Ti, W) C powder, 1.8 μm Co powder,
And 1.2 μm carbon (C) powder were prepared, and these raw material powders were respectively blended into the blending compositions shown in Table 7,
Further, the wax was added, and the mixture was ball-milled in acetone for 24 hours, dried under reduced pressure, and press-molded into various compacts having a predetermined shape at a pressure of 100 MPa. 13 ° C / min.
The temperature was raised to a predetermined temperature in the range of 70 to 1470 ° C., maintained at this temperature for 1 hour, and then sintered under furnace cooling conditions to obtain a diameter of 8 mm.
mm, 13 mm, and 26 mm to form three types of round bar sintered bodies for forming a cemented carbide substrate, and from the three types of round bar sintered bodies, by grinding, in a combination shown in Table 7, The diameter x length of the cutting edge is 6mm x 13mm, 10mm x
Carbide substrates (end mills) a to h having dimensions of 22 mm and 20 mm × 45 mm were produced, respectively.

Next, these super-hard substrates (end mills)
With the honing applied to the surfaces of a to h, the Ti compound layer and the Al layer having the composition and the target layer thickness shown in Table 8 were used under the same conditions as shown in Tables 2 and 3 using a conventional chemical vapor deposition apparatus. By forming a hard coating layer composed of a ₂ O ₃ layer, an outermost surface layer composed of a diffused oxygen-containing Ti oxynitride layer, and an outermost surface underlying layer composed of a diffused oxygen supply Ti oxide layer, FIG. (A) is a schematic front view, and (b) is an end mill made of a surface-coated cemented carbide of the present invention as a coated carbide tool of the present invention having a shape shown by a schematic cross-sectional view of a cutting edge portion (hereinafter, the present invention). (Referred to as coated carbide end mills) 1 to 8 respectively.

For comparison purposes, as shown in Table 9, the outermost surface layer composed of the above-described diffused oxygen-containing Ti oxynitride layer and the outermost surface underlying layer composed of the diffused oxygen-supplying Ti oxide layer are substituted for the above. Thus, under the same conditions except that a TiN layer is formed, a conventional surface-coated cemented carbide end mill (hereinafter referred to as a conventional coated carbide end mill) 1 to 1 as a conventionally coated cemented carbide tool.
8 were each produced.

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 SCM440 plate, Cutting speed: 80 m / min. , Groove depth (cut): 3 mm, Table feed: 500 mm / min, Dry high-speed grooving test of alloy steel, coated carbide end mills 4 to 6 of the present invention and conventional coated carbide end mills 4 to 6 , Work material: Plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS SCM440 plate, Cutting speed: 90 m / min. , Groove depth (cut): 6 mm, Table feed: 500 mm / min, Dry high-speed grooving test of alloy steel, coated carbide end mills 7 and 8 of the present invention and conventional coated carbide end mills 7 and 8 , Work material: Plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS SCM415 plate, Cutting speed: 90 m / min. , Groove depth (cut): 15 mm, table feed: 500 mm / min, dry high-speed grooving test of alloy steel under the following conditions. The length of the cutting groove up to a reduction of 0.2 mm, which is a measure of the service life, was measured. The measurement results are shown in Tables 8 and 9, respectively.

[0026]

[Table 7]

[0027]

[Table 8]

[0028]

[Table 9]

(Example 3) The diameters of 8 mm (for forming the super-hard substrates a to c), 13 mm (for forming the super-hard substrates d to f), and 26 mm (for the super-hard substrate g) produced in Example 2 described above. h
(For forming), the diameter x length of the groove forming portion was 4 mm x 13 mm (the carbide substrate a ') by grinding from the three types of round rod sintered bodies. ~ C '), 8mm
× 22 mm (carbide substrate d ′ to f ′) and 16 mm ×
Carbide substrates (drills) a 'to h' each having a size of 45 mm (carbide substrates g 'and h') were manufactured.

Next, these carbide substrates (drills) a
On the surface of '~ h', the Ti compound layer having the composition and the target layer thickness shown in Table 10 was obtained using the ordinary chemical vapor deposition apparatus under the conditions shown in Tables 2 and 3 with the honing performed. A hard coating layer composed of a hard coating layer composed of an Al ₂ O ₃ layer, a top surface layer composed of a diffused oxygen-containing Ti oxynitride layer, and a top surface layer composed of a diffused oxygen supply Ti oxide layer is formed. As a result, the surface-coated cemented carbide of the present invention as a coated carbide tool of the present invention having a shape shown in a schematic front view in FIG. 3A and a schematic cross-sectional view of a groove forming portion in FIG. Drills (hereinafter referred to as coated carbide drills of the present invention) 1 to 8 were produced.

For comparison purposes, as shown in Table 11, the outermost surface layer composed of the above-described diffused oxygen-containing Ti oxynitride layer and the outermost surface underlying layer composed of the diffused oxygen-supplying Ti oxide layer were replaced with each other. Thus, under the same conditions except that the TiN layer was formed, conventional surface-coated cemented carbide drills (hereinafter, referred to as conventional coated carbide drills) 1 to 8 as conventional coated carbide tools were respectively manufactured.

Next, the above-mentioned coated carbide drills 1 to 8 of the present invention.
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 SCM440 plate, Cutting speed: 50 m / min. , Feed: 0.2 mm / min, Wet high-speed drilling test of alloy steel under the following conditions: coated carbide drills 4 to 6 of the present invention and conventional coated carbide drills 4 to
About 6, work material: plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS SCM440 plate, Cutting speed: 60 m / min. , Feed: 0.2 mm / min, wet high-speed drilling test of alloy steel under the following conditions: coated carbide drills 7 and 8 of the present invention and coated carbide drills 7 of the prior art.
For No. 8, Work material: Plane dimensions: 100 mm × 250 mm, thickness: 5
0 mm JIS SCM415 plate, Cutting speed: 75 / min. , Feed: 0.35 mm / min, Wet cutting high-speed drilling test of alloy steel under the following conditions, and the flank of the cutting edge at the tip of any wet type (using water-soluble cutting oil) high-speed drilling cutting test. Wear width is 0.
The number of drilling processes up to 3 mm was measured. The measurement results are shown in Tables 10 and 11, respectively.

[0033]

[Table 10]

[0034]

[Table 11]

[0035]

From the results shown in Tables 4 to 11, it can be seen that the outermost surface layer of the hard coating layer is formed of a Ti nitride oxide layer formed by reacting with oxygen diffused from the outermost underlying layer when forming the TiN layer. The coated carbide tool according to the present invention is characterized in that the Ti nitride oxide layer has an extremely low affinity for high-temperature heated chips even in high-speed cutting of steel with high heat generation.
Since it does not adhere to the i-nitride oxide layer, it exhibits excellent wear resistance without chipping on the cutting edge, whereas the outermost layer of the hard coating layer is made of a TiN layer. In the case of coated carbide tools, the chips
Since the TiN layer easily adheres to the N layer and the TiN layer is peeled off together with the other constituent layers by the cutting powder, chipping easily occurs in the cutting blade, and it is apparent that this causes a service life in a relatively short time. It is. As described above, the coated cemented carbide tool of the present invention enables the practical use of the identification tool before and after use, particularly in high-speed cutting of various steels and cast irons. No wear is exhibited, and excellent wear resistance is exhibited over a long period of time.

[Brief description of the drawings]

FIG. 1A is a schematic perspective view of a coated carbide tip, and FIG.
1 is a schematic longitudinal sectional view of a coated carbide tip.

FIG. 2 (a) is a schematic front view of a coated carbide end mill,
(B) is a schematic cross-sectional view of the cutting blade portion.

FIG. 3A is a schematic front view of a coated carbide drill, and FIG.
FIG. 3 is a schematic cross-sectional view of the groove forming portion.

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[Procedure amendment]

[Submission date] October 5, 2000 (2000.10.
5)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0025

[Correction method] Change

[Correction contents]

[0025] The resulting coated carbide endomi according to the present invention is obtained as follows.
Surface layer and surface underlayer constituting hard coating layer 1 to 8
For the layer, the oxygen content ratio at the center in the thickness direction (Y value
And X value) were measured using an Auger spectrometer.
However, the values shown in Table 8 were shown. Next, of the coated carbide end mills 1 to 8 of the present invention and the coated carbide end mills 1 to 8 of the present invention, the coated carbide end mills 1 to 3 of the present invention and the conventionally coated carbide end mills 1 to 3 are: Plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS SCM440 plate, Cutting speed: 80 m / min. , Groove depth (cut): 3 mm, Table feed: 500 mm / min, Dry high-speed grooving test of alloy steel, coated carbide end mills 4 to 6 of the present invention and conventional coated carbide end mills 4 to 6 , Work material: Plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS SCM440 plate, Cutting speed: 90 m / min. , Groove depth (cut): 6 mm, Table feed: 500 mm / min, Dry high-speed grooving test of alloy steel, coated carbide end mills 7 and 8 of the present invention and conventional coated carbide end mills 7 and 8 , Work material: Plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS SCM415 plate, Cutting speed: 90 m / min. , Groove depth (cut): 15 mm, table feed: 500 mm / min, dry high-speed grooving test of alloy steel under the following conditions. The length of the cutting groove up to a reduction of 0.2 mm, which is a measure of the service life, was measured. The measurement results are shown in Tables 8 and 9, respectively.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0027

[Correction method] Change

[Correction contents]

[0027]

[Table 8]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0032

[Correction method] Change

[Correction contents]

The coated carbide drill of the present invention obtained as a result 1
To 8 of the surface layer and the surface underlayer constituting the hard coating layer
Then, the oxygen content ratio at the center in the thickness direction (Y value and
And X value) were measured using an Auger spectrometer.
In addition, the values shown in Table 10 were shown. Next, the coated carbide drills 1 to 8 of the present invention and the conventional coated carbide drills 1 to 8
Among them, the coated carbide drills 1 to 3 of the present invention and the conventionally coated carbide drills 1 to 3 are: work material: plane dimension: 100 mm × 250 mm, thickness: 5
0 mm JIS SCM440 plate, Cutting speed: 50 m / min. , Feed: 0.2 mm / min, Wet high-speed drilling test of alloy steel under the following conditions: coated carbide drills 4 to 6 of the present invention and conventional coated carbide drills 4 to
About 6, work material: plane dimensions: 100 mm x 250 mm, thickness: 5
0 mm JIS SCM440 plate, Cutting speed: 60 m / min. , Feed: 0.2 mm / min, wet high-speed drilling test of alloy steel under the following conditions: coated carbide drills 7 and 8 of the present invention and coated carbide drills 7 of the prior art.
For No. 8, Work material: Plane dimensions: 100 mm × 250 mm, thickness: 5
0 mm JIS SCM415 plate, Cutting speed: 75 / min. , Feed: 0.35 mm / min, Wet cutting high-speed drilling test of alloy steel under the following conditions, and the flank of the cutting edge at the tip of any wet type (using water-soluble cutting oil) high-speed drilling cutting test. Wear width is 0.
The number of drilling processes up to 3 mm was measured. The measurement results are shown in Tables 10 and 11, respectively.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction contents]

[0033]

[Table 10]

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshiaki Ueda 1-297 Kitabukurocho, Omiya City, Saitama Prefecture Mitsubishi Materials Research Institute (72) Inventor Keiji Nakamura 1-297 Kitabukurocho, Omiya City, Saitama Mitsubishi F-term (reference) in Materials Research Laboratory 3C046 FF03 FF10 FF19 FF22 FF25 4K029 AA04 BA41 BA44 BA48 BA54 BA55 BA60 BB02 BC00 BD05 EA01 4K030 BA18 BA35 BA36 BA38 BA41 BA42 BA43 BB12 CA03 JA01 LA22

Claims (1)

[Claims] 1. The method according to claim 1, wherein one or more of a carbide layer, a nitride layer, a carbonitride layer, a carbonate layer, and a carbonitride layer of Ti are formed on the surface of the tungsten carbide-based cemented carbide substrate. A hard coating layer composed of a Ti compound layer and an aluminum oxide layer by chemical vapor deposition and / or physical vapor deposition with an average layer thickness of 3 to 30 μm. In addition, as the outermost surface underlayer,
When it has an average layer thickness of 0.1 to 3 μm and is represented by the composition formula: TiO _x , the central part in the thickness direction is measured by an Auger spectrometer, and the atomic ratio to X: Ti is 1. A Ti oxide layer that satisfies 2 to 1.7, and also has an average layer thickness of 0.05 to 2 μm as the outermost surface layer, and is represented by a composition formula: TiN _1-Y (O) _Y. (However, (O) indicates oxygen diffused from the outermost surface underlayer), the center in the thickness direction is also measured by an Auger spectrometer, and the atomic ratio to Y: Ti is 0.01 to 0. A cutting tool made of a surface-coated cemented carbide having excellent chipping resistance, obtained by chemical vapor deposition and / or physical vapor deposition of a Ti nitride oxide layer satisfying the following condition: