JP2005219199A - Surface coated cemented carbide cutting tool having hard coated layer displaying excellent wear resistance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface coated cemented carbide cutting tool having a hard coated layer displaying excellent wear resistance. <P>SOLUTION: The hard coated layer is formed by vapor deposition on the surface of a substrate made of WC-based cemented carbide or TiCN-based cermet. The layer is made of a (Al, Ti)N layer satisfies a composition formula, (Al<SB>1-x</SB>Ti<SB>x</SB>)N (X shows 0.30 to 0.55 in atomic ratio), showing an inclined angle frequency distribution graph in which a maximum peak exists in inclined angle divisions within the range of 15 to 27° and a total of frequencies existing in the range of 15 to 27° occupies the rate of 45 to 65% of the whole of the frequencies in an inclined angle frequency distribution graph constituted by measuring inclined angles formed by normal lines of ä100} surfaces to be crystal faces of crystal grain, by dividing the measured inclined angles within the range of 0 to 45° for every 0.25° pitch of the measured inclined angles, and by totalizing frequencies existing in each division. The layer also has an average layer thickness of 1 to 15μm. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a surface-coated cemented carbide cutting tool (hereinafter referred to as a coated cemented carbide tool) that exhibits excellent wear resistance with a hard coating layer, especially when cutting steel or cast iron.

  In general, coated carbide tools are used for throwaway inserts that are detachably attached to the tip of a cutting tool for drilling and cutting of various materials such as steel and cast iron, and for flat cutting. There are drills, miniature drills, solid type end mills used for chamfering, grooving, shoulder processing, etc. in which the cutting blade takes an intermittent cutting form, and the solid type by attaching the throwaway tip detachably A slow-away end mill tool that performs a cutting process in the same manner as an end mill is known.

Further, as a coated carbide tool, a substrate composed of tungsten carbide (hereinafter referred to as WC) -based cemented carbide alloy or titanium carbonitride (hereinafter referred to as TiCN) -based cermet (hereinafter collectively referred to as a cemented carbide substrate). A composite nitride of Al and Ti satisfying the composition formula: (Al _1-X Ti _X ) N (wherein X represents 0.30 to 0.55 by atomic ratio) [hereinafter, Coated carbide tools formed by physical vapor deposition of a hard coating layer composed of (Al, Ti) N] layers with an average layer thickness of 1 to 15 μm have been proposed. Continuous cutting and intermittent cutting of various steels and cast iron It is used for.

Furthermore, the above-mentioned coated carbide tool is equipped with the above-mentioned carbide substrate in an arc ion plating apparatus which is one type of physical vapor deposition apparatus schematically shown in FIG.
In-apparatus heating temperature: 300-500 ° C
DC bias voltage applied to the carbide substrate: -600 to -1000 V,
Cathode electrode: metal titanium (Ti),
Arc discharge current between the cathode electrode and the anode electrode: 60 to 100 A
Processing time: 1-10 minutes,
Under the above conditions, the surface of the carbide substrate was cleaned with Ti bombardment, and the interior of the apparatus was heated with a heater, for example, at a temperature of 500 ° C., and an Al—Ti alloy having a predetermined composition was set. Arc discharge is generated between the cathode electrode (evaporation source), for example, at a current of 90 A, and simultaneously, nitrogen gas is introduced into the apparatus as a reaction gas to form a reaction atmosphere of 2 Pa, for example. Is also known to be produced by evaporating a hard coating layer made of the (Al, Ti) N layer on the surface of the cemented carbide substrate under the condition that a bias voltage of -100 V is applied, for example. .
Japanese Patent No. 2644710

  In recent years, there has been a strong demand for labor saving, energy saving, and cost reduction for cutting, and along with this, coated carbide tools tend to require a much longer life. In tools, the wear progress of the (Al, Ti) N layer, which is a hard coating layer, is relatively fast, and as a result, the service life is reached in a relatively short time.

Therefore, the present inventors, from the above viewpoint, paying attention to the hard coating layer of the above conventional coated carbide tool, as a result of conducting research to improve this one-stage wear resistance,
(A) Using the arc ion plating apparatus shown in FIG. 4, instead of the above-described conventional Ti bombard cleaning treatment for the carbide substrate surface,
In-apparatus heating temperature: 300-500 ° C
DC bias voltage applied to the carbide substrate: -600 to -1000 V,
Cathode electrode: metallic tungsten (W),
Arc discharge current between the cathode electrode and the anode electrode: 60 to 100 A,
Processing time: 1-10 minutes,
Under the conditions described above, the above-described composition formula: (Al _1-X Ti _X ) N When an (Al, Ti) N layer satisfying (atomic ratio, X represents 0.30 to 0.55) is formed, the resulting (Al, Ti) N layer has a long-term excellent resistance. To be able to show wear.

(B) Surface polishing of the (Ti, Al) N layer of (a) and the conventional (Ti, Al) N layer described above using a field emission scanning electron microscope, as schematically shown in FIG. A crystal grain having a cubic crystal lattice existing within the measurement range of the plane is irradiated with an electron beam, and the method of the {100} plane which is the crystal plane of the crystal grain with respect to the normal line of the surface polished surface Measure the tilt angle formed by the line, and divide the measured tilt angles within the range of 0 to 45 degrees out of the measured tilt angles by pitch of 0.25 degrees, and count the frequencies existing in each section When the inclination angle number distribution graph is created, the conventional (Ti, Al) N layer has a measured inclination angle distribution on the {100} plane within the range of 0 to 45 degrees as illustrated in FIG. Shows an unbiased inclination angle number distribution graph, while the inclination of the (Ti, Al) N layer in (a) above is shown. In the angle distribution graph, as illustrated in FIG. 2, a sharp maximum peak appears at a specific position of the inclination angle section, and this sharp maximum peak is obtained during surface modification treatment in which the carbide substrate surface is bombarded with W. By changing the arc discharge current between the metal W as the cathode electrode and the anode electrode, the position appearing in the tilt angle section of the horizontal axis of the graph is changed.

(C) According to many test results, when the arc discharge current between the cathode electrode and the anode electrode is changed within the range of 60 to 100 A as described above, the sharp maximum peak is 15 to 27 of the inclination angle section. As shown in the slope angle distribution graph, which appears in the range of degrees and the total of the frequencies existing in the range of 15 to 27 degrees occupies a ratio of 45 to 65% of the whole degrees in the slope angle distribution graph. Therefore, a coated carbide tool formed by forming a (Ti, Al) N layer as a hard coating layer showing such an inclination angle number distribution graph will exhibit excellent wear resistance over a long period of time.
The research results shown in (a) to (c) above were obtained.

The present invention has been made based on the above research results, and the surface of a cemented carbide substrate made of a WC-based cemented carbide or TiCN-based cermet is used.
Composition formula: (Al _1-X Ti _X ) N (wherein, X is 0.30 to 0.55 in atomic ratio) is satisfied,
And, using a field emission scanning electron microscope, irradiating an electron beam to each crystal grain having a cubic crystal lattice existing in the measurement range of the surface polished surface, the normal to the surface polished surface, The inclination angle formed by the normal line of the {100} plane, which is the crystal plane of the crystal grain, is measured, and the measurement inclination angle within the range of 0 to 45 degrees out of the measurement inclination angles is set for every 0.25 degree pitch. In the inclination angle distribution graph obtained by summing up the frequencies existing in each section, the highest peak is present in the inclination angle section in the range of 15 to 27 degrees, and within the range of 15 to 27 degrees. (Al, Ti) N layer having an average layer thickness of 1 to 15 μm, showing the inclination angle distribution graph in which the total number of frequencies present in the inclination angle distribution graph occupies a ratio of 45 to 65% of the entire frequency in the inclination angle distribution graph ,
The hard coating layer formed by forming a hard coating layer is characterized by a coated carbide tool exhibiting excellent wear resistance.

  In the (Al, Ti) N layer constituting the hard coating layer of the coated carbide tool of the present invention, the Ti component improves the high temperature strength, while the Al component improves the high temperature hardness and heat resistance (high temperature characteristics). Therefore, when the X value indicating the content ratio of the Ti component is less than 0.30 in terms of the total amount with the Al component (atomic ratio), the proportion of Al is relatively increased. Thus, a decrease in the high-temperature strength of the layer itself is unavoidable, and as a result, chipping or the like is likely to occur. On the other hand, when the X value indicating the Ti ratio exceeds 0.55, the Al ratio is relatively small. Since the desired excellent high-temperature characteristics cannot be secured, the X value is determined to be 0.30 to 0.55, and when the average thickness of the hard coating layer is less than 1 μm Ensure the desired wear resistance Can not, on the other hand when the average layer thickness exceeds 15 [mu] m, since the chipping is likely to occur, it's the average layer thickness was defined as 1 to 15 m.

  In addition, as described above, the highest peak position of the measured inclination angle in the inclination angle number distribution graph of the (Ti, Al) N layer changes by changing the arc discharge current between the cathode electrode and the anode electrode. As a result of the test, when the arc discharge current is 60 to 100 A, the maximum peak appears in the inclination angle section within the range of 15 to 27 degrees, and the total of the frequencies existing within the range of 15 to 27 degrees is The conclusion is reached that a slope angle distribution graph occupying a proportion of 45 to 65% of the entire frequency in the slope angle distribution graph can be obtained. Therefore, even when the arc discharge current is less than 60 A, Even if it exceeds 100 A, the maximum peak position of the measured tilt angle is out of the range of 15 to 27 degrees. In such a case, the desired excellent wear resistance is exhibited. It shall not be.

  In the coated carbide tool of the present invention, particularly when cutting steel or cast iron, the hard coating layer exhibits an excellent wear resistance and contributes to the extension of the service life.

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

As raw material powders, WC powder, TiC powder, VC powder, TaC powder, NbC powder, Cr ₃ C ₂ powder, and Co powder, all having an average particle diameter of 1 to 3 μm, were prepared. And then wet-mixed with a ball mill for 72 hours, dried, and press-molded into a green compact at a pressure of 100 MPa. The green compact was vacuumed at 6 Pa at a temperature of 1400 ° C. for 1 hour. Sintered under the holding conditions, and after sintering, the cutting edge portion was subjected to a honing process of R: 0.03, and the carbide bases A1 to A10 made of WC-based cemented carbide having ISO / CNMG120408 chip shape Formed.

In addition, as raw material powders, all are TiCN (weight ratio TiC / TiN = 50/50) powder, Mo ₂ C powder, ZrC powder, NbC powder, TaC powder, WC powder having an average particle diameter of 0.5 to 2 μm. Co powder and Ni powder are prepared, and these raw material powders are blended in the blending composition shown in Table 2, wet mixed by a ball mill for 24 hours, dried, and then pressed into a compact at a pressure of 100 MPa. The green compact was sintered in a nitrogen atmosphere of 2 kPa at a temperature of 1500 ° C. for 1 hour, and after sintering, the cutting edge portion was subjected to a honing process of R: 0.03 to obtain ISO standard / CNMG120408. The carbide substrates B1 to B6 made of TiCN base cermet having the following chip shape were formed.

  Next, each of the above-mentioned carbide substrates A1 to A10 and B1 to B6 was ultrasonically cleaned in acetone and dried, and mounted on the arc ion plating apparatus shown in FIG. ), An Al—Ti alloy having various component compositions and a metal W for carbide substrate surface modification treatment are mounted. First, the apparatus is evacuated and kept at a vacuum of 0.5 Pa or less with a heater. After heating the inside of the apparatus to 500 ° C., a DC bias voltage of −800 V is applied to the cemented carbide substrate, and a predetermined current in the range of 60 to 100 A is applied between the metal W of the cathode electrode and the anode electrode. The surface of the cemented carbide substrate is subjected to a W bombarding treatment for 5 minutes by generating an arc discharge for 5 minutes, and then nitrogen gas is introduced into the apparatus as a reaction gas to react for 2 Pa. A DC bias voltage of −100 V is applied to the cemented carbide substrate and a current of 100 A is passed between the cathode electrode Al—Ti alloy and the anode electrode to generate an arc discharge. By depositing an (Al, Ti) N layer having the target composition and target layer thickness shown in Table 3 on the surface of the cemented carbide substrate, the throwaway of the surface coated cemented carbide of the present invention as the coated carbide tool of the present invention. Chips (hereinafter referred to as the present coated carbide chips) 1 to 16 were produced.

Further, for the purpose of comparison, the arc ion plating apparatus of FIG. 5 is used, and the above-mentioned carbide substrate surface is replaced with the above-described carbide surface modification treatment by W bombardment treatment.
In-apparatus heating temperature: 500 ° C
DC bias voltage applied to the carbide substrate: -800V,
Cathode electrode: Ti metal,
Arc discharge current: a predetermined current in the range of 60-100A,
Processing time: 5 minutes
The conventional surface as a conventional coated carbide tool as shown in Table 4 by depositing an (Al, Ti) N layer under the same conditions except that the surface of the carbide substrate was subjected to a Ti bombard cleaning process under the conditions of Slow away tips made of coated cemented carbide (hereinafter referred to as conventional coated cemented carbide tips) 1 to 16 were produced.

Next, with the present invention coated carbide tips 1-16 and conventional coated carbide tips 1-16, in a state where this is screwed to the tip of the tool steel tool with a fixing jig,
Work material: JIS / SNCM439 round bar,
Cutting speed: 200 m / min. ,
Incision: 1.5mm,
Feed: 0.3 mm / rev. ,
Cutting time: 10 minutes,
Dry continuous cutting test of alloy steel under the conditions of
Work material: JIS · S45C lengthwise equal 4 round grooved round bars,
Cutting speed: 180 m / min. ,
Cutting depth: 1.2mm,
Feed: 0.25 mm / rev. ,
Cutting time: 10 minutes,
Dry interrupted machining test of carbon steel under the conditions of
Work material: JIS / FC300 round bar,
Cutting speed: 220 m / min. ,
Cutting depth: 1.2mm,
Feed: 0.25 mm / rev. ,
Cutting time: 10 minutes,
The dry continuous cutting test of cast iron was performed under the conditions described above, and the flank wear width of the cutting edge was measured in any cutting test. The measurement results are shown in Table 5.

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 [50/50 by mass ratio] powder, and 1.8 μm Co Prepare powders, mix each of these raw material powders with the composition shown in Table 6, add wax, ball mill mix in acetone for 24 hours, dry under reduced pressure, and then press various pressures of a predetermined shape at a pressure of 100 MPa. The powder compact is press-molded, and these green compacts are heated to a predetermined temperature in the range of 1370 to 1470 ° C. at a heating rate of 7 ° C./min in a vacuum atmosphere of 6 Pa, and this temperature is maintained for 1 hour. After holding, sintering under furnace cooling conditions, the diameter is 8m , 13 mm, and 26 mm round bar sintered bodies for forming a cemented carbide substrate were formed, and the above three types of round bar sintered bodies were cut into the combinations shown in Table 6 by grinding. Carbide substrate (end mill) C- having a shape of a four-blade square with a blade portion diameter × length of 6 mm × 13 mm, 10 mm × 22 mm, and 20 mm × 45 mm, respectively, and a twist angle of 30 degrees. 1 to C-8 were produced.
Separately, by a field emission scanning electron microscope having the same composition as the above-mentioned carbide substrates (end mills) C-1 to C-8, and each having dimensions of plane: 12 mm × 12 mm, thickness: 6 mm. A test piece for preparing an inclination angle number distribution graph was prepared.

  Then, these carbide substrates (end mills) C-1 to C-8 and test pieces were ultrasonically cleaned in acetone and dried, and then loaded into the arc ion plating apparatus shown in FIG. The coating of the present invention was carried out by subjecting the carbide substrate surface modification treatment under the same conditions as in Example 1 above and depositing an (Al, Ti) N layer having the target composition and target layer thickness shown in Table 7. The surface-coated cemented carbide end mills (hereinafter referred to as the present invention coated carbide end mills) 1 to 8 as cemented carbide tools were produced, respectively.

  Further, for the purpose of comparison, the surface of the above-mentioned carbide substrate is subjected to the same conditions as in Example 1 except that Ti bombard cleaning is performed instead of the above-described carbide substrate surface modification treatment. By vapor-depositing an (Al, Ti) N layer, as shown in Table 7 (a conventional surface-coated cemented carbide end mill (hereinafter referred to as a conventional coated carbide end mill) 1 to 1 as a conventional coated carbide tool) 8 were produced respectively.

Next, of the present invention coated carbide end mills 1-8 and conventional coated carbide end mills 1-8, the present invention coated carbide end mills 1-3 and conventional coated carbide end mills 1-3 are as follows:
Work material: Plane dimensions: 100 mm × 250 mm, thickness: 50 mm JIS / SKD61 plate material,
Cutting speed: 45 m / min. ,
Groove depth (cut): 0.25 mm,
Table feed: 180mm / min,
With respect to the dry grooving test of tool steel under the conditions of the present invention, the coated carbide end mills 4 to 6 and the conventional coated carbide end mills 4 to 6 of the present invention,
Work material: Plane dimension: 100 mm × 250 mm, thickness: 50 mm JIS / S55C plate material,
Cutting speed: 100 m / min. ,
Groove depth (cut): 2.5 mm,
Table feed: 600 mm / min,
For the dry grooving test of carbon steel under the conditions of the present invention, the coated carbide end mills 7 and 8 of the present invention and the conventional coated carbide end mills 7 and 8,
Work material: Plane dimension: 100 mm × 250 mm, thickness: 50 mm JIS / SCM440 plate material,
Cutting speed: 110 m / min. ,
Groove depth (cut): 0.4 mm,
Table feed: 300mm / min,
Each of the alloy steels was subjected to a dry grooving test under the conditions described above, and in each grooving test, cutting was performed until the flank wear width of the outer peripheral edge of the cutting edge reached 0.1 mm, which is a guide for the service life. The groove length was measured. The measurement results are shown in Table 7, respectively.

The diameters produced in Example 2 above were 8 mm (for forming carbide substrates C-1 to C-3), 13 mm (for forming carbide substrates C-4 to C-6), and 26 mm (for carbide substrates C-). 7, for C-8 formation), from these three types of round bar sintered bodies, the diameter x length of the groove forming portion is 4 mm x 13 mm (by grinding), respectively. Carbide substrates D-1 to D-3), 8 mm × 22 mm (Carbide substrates D-4 to D-6), and 16 mm × 45 mm (Carbide substrates D-7 and D-8), and all Carbide substrates (drills) D-1 to D-8 having a two-blade shape with a twist angle of 30 degrees were produced.
Similarly, by using a field emission scanning electron microscope having the same composition as the above-mentioned carbide substrates (drills) D-1 to D-8 and having dimensions of plane: 12 mm × 12 mm and thickness: 6 mm. A specimen for preparing an inclination angle number distribution graph was also prepared.

  Next, the cutting edges of these carbide substrates (drills) D-1 to D-8 were honed, and ultrasonically cleaned in acetone together with the above test pieces and dried, as shown in FIG. And the carbide substrate surface modification treatment is performed under the same conditions as in Example 1, and the target composition and target layer thickness (Al, Ti) N shown in Table 8 are used. By vapor-depositing the layers, drills made of the surface-coated cemented carbide of the present invention (hereinafter referred to as “coated carbide drill of the present invention”) 1 to 8 as the coated carbide tools of the present invention were produced.

  Further, for the purpose of comparison, the surface of the above-mentioned carbide substrate is subjected to the same conditions as in Example 1 except that Ti bombard cleaning is performed instead of the above-described carbide substrate surface modification treatment. By depositing an (Al, Ti) N layer, conventional surface-coated cemented carbide drills (hereinafter referred to as conventional coated carbide drills) 1 to 8 as conventional coated carbide tools as shown in Table 8 are used. Each was manufactured.

Next, of the present invention coated carbide drills 1-8 and conventional coated carbide drills 1-8, the present invention coated carbide drills 1-3 and conventional coated carbide drills 1-3,
Work material: Plane dimensions: 100 mm × 250 mm, thickness: 50 mm JIS / SKD61 plate material,
Cutting speed: 30 m / min. ,
Feed: 0.1 mm / rev,
Hole depth: 8mm
For the wet drilling cutting test of the tool steel under the conditions of the present invention, the coated carbide drills 4-6 of the present invention and the conventional coated carbide drills 4-6,
Work material: Plane dimensions: 100 mm × 250 mm, thickness: 50 mm JIS / FC200 plate material,
Cutting speed: 60 m / min. ,
Feed: 0.25mm / rev,
Hole depth: 16mm
For cast iron wet drilling test under the conditions of the present invention, the present invention coated carbide drills 7 and 8 and the conventional coated carbide drills 7 and 8,
Work material: Plane dimensions: 100 mm × 250 mm, thickness: 50 mm JIS / SCM435 plate material,
Cutting speed: 40 m / min. ,
Feed: 0.2mm / rev,
Hole depth: 32mm
Wet drilling test of alloy steel under the conditions of each, and drilling until the flank wear width of the cutting edge surface reaches 0.3mm in any wet drilling test (using water-soluble cutting oil) The number of processes was measured. The measurement results are shown in Table 8.

As a result, the coated carbide tips 1 to 16 of the present invention, the coated carbide end mills 1 to 8 of the present invention, the coated carbide drills 1 to 8 of the present invention, and the conventionally coated carbide tools of the present invention. The composition of the (Al, Ti) N layer of conventional coated carbide tips 1 to 16, conventional coated carbide end mills 1 to 8, and conventional coated carbide drills 1 to 8 was measured using an Auger spectroscopic analyzer. Each showed substantially the same composition as the target composition.
Moreover, when the thickness of the (Al, Ti) N layer of these coated carbide tools of the present invention and the conventional coated carbide tools was measured with a scanning electron microscope, both were substantially the same as the target values. The average layer thickness (average value of 5-point measurement) was shown.

Further, an inclination angle number distribution graph was created for each of the (Al, Ti) N layers of the present invention coated carbide tool and the conventional coated carbide tool using a field emission scanning electron microscope.
That is, the inclination angle number distribution graph is set in a lens barrel of a field emission scanning electron microscope with the surface of the (Ti, Al) N layer as a polished surface, and 70 ° An electron beam having an acceleration voltage of 15 kV at an incident angle is irradiated at an irradiation current of 1 nA to each crystal grain having a cubic crystal lattice existing within the measurement range of the surface polished surface, and an electron backscatter diffraction image apparatus is used. , Measuring the inclination angle formed by the normal of the {100} plane, which is the crystal plane of the crystal grain, with respect to the normal of the polished surface at an interval of 0.1 μm / step in a 30 × 50 μm region Based on the measurement results, the measurement inclination angles within the range of 0 to 45 degrees out of the measurement inclination angles are divided for each pitch of 0.25 degrees, and the frequencies existing in each division are tabulated. Created by.

In the distribution graph of the inclination angle numbers of the various (Al, Ti) N layers obtained as a result, the (Al, Ti) N layer of the coated carbide tool of the present invention is shown in Table 3, Table 7, and Table 8, respectively. As shown in the graph, the distribution of the measured inclination angle of the {100} plane shows the inclination angle number distribution graph in which the highest peak appears in the inclination angle section within the range of 15 to 27 degrees, whereas the conventional coated carbide tool As shown in Table 4, Table 7, and Table 8, the (Ti, Al) N layer is all unbiased in the range of the measured inclination angle of {100} plane within the range of 0 to 45 degrees. An inclination angle number distribution graph in which no peak exists is shown.
Tables 3, 4, 7, and 8 show 15 to 27 degrees in the gradient angle distribution graph of the (Ti, Al) N layer of the above-described coated carbide tool of the present invention and the conventional coated carbide tool. The ratio of the number of tilt angles existing in the tilt angle section within the range of the total angle of the graph is shown.
2 is an inclination angle number distribution graph of the (Al, Ti) N layer of the coated carbide tip 1 of the present invention, and FIG. 3 is an inclination angle number of the (Al, Ti) N layer of the conventional coated carbide tip 1. Each distribution graph is shown.

  From the results shown in Tables 3 to 8, the coated carbide tool of the present invention has a {100} plane of the (Al, Ti) N layer constituting the hard coating layer of 15 to 27 degrees in an inclination angle number distribution graph. In contrast to the highest peak in the range of tilt angle and excellent wear resistance, the hard coating is unbiased in the range of the measured tilt angle of the {100} plane in the range of 0 to 45 degrees. In the conventional coated carbide tool composed of (Ti, Al) N layer, which shows a gradient angle distribution graph without the highest peak, the wear progress is relatively fast and the service life is reached in a relatively short time. Is clear.

  As described above, the coated carbide tool of the present invention exhibits excellent wear resistance in continuous cutting and intermittent cutting of various steels and cast irons, and exhibits excellent cutting performance over a long period of time. It can fully satisfy the labor-saving and energy-saving of cutting, and also the cost reduction.

It is a schematic explanatory drawing which shows the measuring range of the inclination angle with respect to the normal line of the surface polished surface, with the normal line of the {100} plane which is the crystal plane of the crystal grains in various (Al, Ti) N layers constituting the hard coating layer. It is an inclination angle number distribution graph of the {100} plane of the (Al, Ti) N layer constituting the hard coating layer of the coated carbide chip 1 of the present invention. It is a gradient angle number distribution graph of the {100} plane of the (Al, Ti) N layer constituting the hard coating layer of the conventional coated carbide chip 1. It is a schematic explanatory drawing of the arc ion plating apparatus used for formation of the (Al, Ti) N layer which comprises the hard coating layer of this invention coated carbide tool. It is a schematic explanatory drawing of the arc ion plating apparatus used for formation of the (Al, Ti) N layer which comprises the hard coating layer of the conventional coated carbide tool.

Claims (1)

On the surface of the substrate composed of tungsten carbide-based cemented carbide or titanium carbonitride-based cermet,
Composition formula: (Al _1-X Ti _X ) N (wherein, X is 0.30 to 0.55 in atomic ratio) is satisfied,
And, using a field emission scanning electron microscope, irradiating an electron beam to each crystal grain having a cubic crystal lattice existing in the measurement range of the surface polished surface, the normal to the surface polished surface, The inclination angle formed by the normal line of the {100} plane, which is the crystal plane of the crystal grain, is measured, and the measurement inclination angle within the range of 0 to 45 degrees out of the measurement inclination angles is set for every 0.25 degree pitch. In the inclination angle distribution graph obtained by summing up the frequencies existing in each section, the highest peak is present in the inclination angle section in the range of 15 to 27 degrees, and within the range of 15 to 27 degrees. 2 shows an inclination angle distribution graph in which the sum of the frequencies existing in the inclination angle distribution graph accounts for 45 to 65% of the entire frequency in the inclination angle distribution graph, and has an average layer thickness of 1 to 15 μm. layer,
A coated cemented carbide cemented carbide cutting tool that exhibits a high wear resistance with a hard coating layer.

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