JP2007038373A - Surface-coated cemented-carbide cutting tool with hard coating layer showing excellent chipping resistance in cutting difficult-to-cut material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface-coated cemented-carbide cutting tool with a hard coating layer showing excellent chipping resistance in cutting a difficult-to-cut material. <P>SOLUTION: The surface-coated cemented-carbide cutting tool has the hard coating layer on the surface of a cemented carbide base body composed of tungsten-carbide-based cemented carbide alloy or titanium-carbonitride-based cermet. The hard coating layer is composed of (a) a lower layer which has a mean layer thickness of 1 to 5 μm, and is composed of a (Ti, Al)N layer satisfying the following composition formula, (Ti<SB>1-X</SB>Al<SB>X</SB>)N, where X is 0.30 to 0.70 in a atomic ratio; (b) an interlayer adhesive layer composed of a vanadium nitride layer having a mean layer thickness of 0.1 to 1.5 μm; and (c) an upper layer which has a mean layer thickness of 1 to 5 μm, and is composed of a V-diffused VO<SB>M</SB>layer having a texture in which a metal V of 0.5 to 7 atm.% in a ratio occupied in the total amount including VO<SB>M</SB>is dispersively distributed in a matrix of VO<SB>M</SB>(vanadium oxide). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  This invention is a cutting tool made of a surface-coated cemented carbide alloy (hereinafter referred to as coated carbide) that exhibits excellent chipping resistance with a hard coating layer, especially when machining difficult-to-cut materials such as stainless steel, high manganese steel, and even mild steel. Tool).

  Generally, for coated carbide tools, a throw-away tip that is attached to the tip of a cutting tool for turning or flattening of various steel and cast iron work materials, and drilling of the work material. There are drills and miniature drills used for processing, etc., and solid type end mills used for chamfering, grooving, shoulder processing, etc. of the work material. A slow-away end mill tool that performs cutting work in the same manner as a type end mill is known.

Further, as a coated carbide tool, on the surface of a carbide substrate composed of tungsten carbide (hereinafter referred to as WC) -based cemented carbide or titanium carbonitride (hereinafter referred to as TiCN) -based cermet,
Composition formula: (Ti _1-X Al _X ) N (however, in atomic ratio, X represents 0.30 to 0.70),
There is known a coated carbide tool formed by physical vapor deposition of a hard coating layer composed of a composite nitride of Ti and Al [hereinafter referred to as (Ti, Al) N] layer satisfying the following conditions with an average layer thickness of 1 to 15 μm. And the (Ti, Al) N layer, which is a hard coating layer of the coated carbide tool, has high temperature hardness and heat resistance due to Al as a component, and high temperature strength due to the Ti. It is also known to exhibit excellent cutting performance when used for continuous cutting and intermittent cutting of various general steels and ordinary cast iron.

Furthermore, the above-mentioned coated carbide tool is, for example, the above-mentioned carbide substrate is inserted into an arc ion plating apparatus which is one type of physical vapor deposition apparatus schematically shown in FIG. For example, in a state heated to a temperature of 500 ° C., an arc discharge is generated between the anode electrode and the cathode electrode (evaporation source) in which a Ti—Al alloy having a predetermined composition is set, for example, under a current of 90 A, At the same time, nitrogen gas is introduced into the apparatus as a reaction gas to give a reaction atmosphere of, for example, 2 Pa. On the other hand, the carbide substrate is applied with a bias voltage of, for example, −100 V on the surface of the carbide substrate. It is also known that it is produced by vapor-depositing a hard coating layer composed of a (Ti, Al) N layer.
Japanese Patent No. 2644710

  In recent years, the use of FA for cutting devices has been remarkable. On the other hand, there is a strong demand for labor saving, energy saving, and cost reduction for cutting processing. As a result, cutting tools are affected as much as possible by the type of work material. There is a tendency to demand cutting tools that can cut as many grades as possible, but in the above-mentioned conventional coated carbide tools, this is applied to general steels such as low alloy steels and carbon steels. There is no problem when used for cutting of ordinary cast iron such as ductile cast iron and gray cast iron, but especially stainless steel, high manganese steel, and mild steel with high chip viscosity and easy welding to the tool surface. When cutting difficult-to-cut materials, the work material and chips made of difficult-to-cut materials are heated to a high temperature due to the heat generated during cutting, and the viscosity increases further. On the layer surface Tackiness and become reactive increases further to this result chipping in the cutting edge (small chipping) increases rapidly, which is at present, leading to a relatively short time service life due.

Therefore, the present inventors, from the viewpoint as described above, particularly in cutting of difficult-to-cut materials,
In order to develop a coated carbide tool that exhibits excellent chipping resistance with a hard coating layer, as a result of research conducted focusing on the above conventional coated carbide tool,
(A) A (Ti, Al) N layer, which is a hard coating layer of the above-mentioned conventional coated carbide tool, is formed with an average layer thickness of 1 to 5 μm as a lower layer, and a vanadium oxide (hereinafter referred to as VO) as an upper layer thereon. _M represents a change value of the relative content ratio of oxygen to vanadium (V), and the atomic ratio indicates VO, V ₂ O ₃ , V ₂ O ₅ , VO _2, etc.) cutting edge to form with an average layer thickness of 1 to 5 [mu] m, the VO _M layer is excellent surface slipperiness, even when this result workpiece by heat generated during cutting (difficult-to-cut materials) and its cutting scraps is high temperature heating Excellent slipperiness is always ensured between the part (the rake face and the flank face, and the cutting edge ridge line where these two surfaces intersect) and the work material and the chip, and the work material and the cutting edge part of the chip The adhesiveness and reactivity to the surface is significantly reduced, the lower layer ( i, Al) N-layer because it sufficiently protect, (Ti, Al) having excellent characteristics N layer may become to be sufficiently exhibited for a long time.

(B) the the VO _M and matrix constituting the VO _M layer (a), which the VO _M and 0.5 to 7 atomic% of vanadium metal as a percentage of the total amount (hereinafter, indicated by metal V ) a dispersing contained, the metal V into a green body of VO _M is a V dispersed VO _M layer having dispersed distribution organization, in the V dispersed VO _M layer of this result, the metal V to disperse distribution into a green body, the cutting by oxidation with highly exothermic atmosphere with time, but the VO _M, since it acts to significantly suppress the wear progress of green bodies this product VO _M consists likewise VO _M, the VO _M layer of the (a) Be superior to wear resistance.

Further, V dispersed VO _M layer described above, for example, a metal V powder was heated oxidized in an oxidizing atmosphere and VO _M powder, this mixed a predetermined amount of the metal V powder, mixed and press-molded into a powder compact after, the green compact in an Ar atmosphere, and sintered under the conditions of 1 hour hold time at a temperature of 1300 ° C., to produce a V dispersion VO _M sintered body, the resulting V dispersed VO _M sintering The body can be formed by sputtering vapor deposition in an Ar atmosphere using the cathode electrode of the sputtering apparatus. ,
(C) On the other hand, a V dispersion VO _M layer and the lower layer is the upper layer of the (Ti, Al) adhesion to the N layer is not sufficient, the adhesion of the interlayer particularly when subjected to intermittent cutting Although easily chipping occurs sexual because of lack of the average vanadium nitride (hereinafter indicated by VN) layer of 0.1~1.5μm between the V dispersion VO _M layer and (Ti, Al) N layer When interposing a layer thickness, the VN layer the V dispersed VO _M layer and (Ti, Al) since the firmly adhered with any of the N layer, so adhesion with superior in these two layers is ensured To become a.

(D) The hard coating layer constituted by the above (a) to (c) is, for example, an arc ion plating apparatus having a structure shown in a schematic plan view in FIG. 1 (a) and a schematic front view in (b). (Hereinafter abbreviated as AIP apparatus) and sputtering apparatus (hereinafter abbreviated as SP apparatus) coexisting vapor deposition apparatus, that is, a rotating table for mounting a carbide substrate is provided at the center of the apparatus, metal V as a cathode electrode of the AIP device side (evaporation source), a cathode electrode (vapor source) as V dispersion VO _M sintered body of the SP device on the other side opposed, further along the rotary table, and deposition apparatus arranged Ti-Al alloy having a predetermined composition as a cathode electrode (vapor source) of the same AIP device in a position 90 degrees apart from each of the metal V and V dispersed VO _M sintered body A plurality of carbide substrates are mounted in a ring shape along the outer peripheral portion at a position that is a predetermined distance in the radial direction from the central axis on the rotary table of the apparatus, and the atmosphere in the apparatus is set as a nitrogen atmosphere in this state. The rotary table is rotated, and a plurality of carbide substrates are mounted in a ring shape along the outer peripheral portion at a predetermined distance in the radial direction from the central axis on the rotary table of the apparatus. First, the Ti—Al alloy cathode electrode is first rotated while rotating the rotary table in a nitrogen atmosphere and rotating the carbide substrate itself for the purpose of uniforming the thickness of the hard coating layer formed by vapor deposition. An arc discharge is generated between the (evaporation source) and the anode electrode, and a (Ti, Al) N layer is deposited on the surface of the cemented carbide substrate as a lower layer with an average layer thickness of 1 to 5 μm. Arc discharge between the cathode electrode (evaporation source) of the Ti—Al alloy and the anode electrode is stopped, and the metal V as the cathode electrode (evaporation source) and the anode electrode are kept while maintaining the atmosphere in the apparatus in a nitrogen atmosphere. And VN layer is deposited as an interlayer adhesion layer with an average layer thickness of 0.1 to 1.5 μm, and the atmosphere in the deposition apparatus is changed to an Ar atmosphere, and the SP apparatus formed by depositing cathode electrode V dispersed VO _M layer with an average layer thickness of 1~5μm as an upper layer overlapping the VN layer disposed was performed sputtering of V dispersion VO _M sintered body as (evaporation source) of What you can do.

(E) A coated cemented carbide tool formed by vapor-depositing a hard coating layer composed of the lower layer, the interlayer adhesion layer, and the upper layer is a stainless steel, a high manganese steel, and a mild steel that are particularly highly viscous and sticky. In the cutting of difficult-to-cut materials such as (Ti, Al) N layer, the lower layer (Ti, Al) N layer has excellent high-temperature hardness and heat resistance, and excellent high-temperature strength, and the intervening VN layer as an interlayer adhesion layer by the action of V dispersion VO _M layer adhesion bonding properties is secured for excellent between the lower layer, excellent surface slipperiness between the flame cut materials and chips is ensured, the flame-cut materials and Cutting is performed with the chip's adhesiveness and reactivity to the cutting edge surface being significantly reduced, so there is no chipping at the cutting edge and excellent wear resistance over a long period of time. To come out.
The research results shown in (a) to (e) above were obtained.

This invention was made based on the above research results, and on the surface of the carbide substrate,
(A) It has an average layer thickness of 1 to 5 μm and satisfies the composition formula: (Ti _1-X Al _X ) N (wherein X represents 0.30 to 0.70 in terms of atomic ratio). A lower layer comprising a (Ti, Al) N layer;
(B) an interlayer adhesion layer comprising a VN layer having an average layer thickness of 0.1 to 1.5 μm;
(C) it has an average layer thickness of 1 to 5 [mu] m, and the matrix of VO _M, a percentage of the total amount of the VO _M, with a tissue 0.5 to 7 atomic% of the metal V are dispersed distribution An upper layer consisting of V-dispersed VO _M layers;
It is characterized by a coated cemented carbide tool that forms a hard coating layer composed of the above (a) to (c) and exhibits excellent chipping resistance in cutting of difficult-to-cut materials. is there.

  Next, the reason why the numerical values of the constituent layers of the hard coating layer of the coated carbide tool of the present invention are limited as described above will be described.

(A) Lower layer composition and average layer thickness The Al component in the (Ti, Al) N layer constituting the lower layer has the effect of improving the high temperature hardness and heat resistance, and the Ti component improves the high temperature strength. When the X value indicating the proportion of Ti is less than 0.30 in terms of the total amount with Ti (atomic ratio, the same shall apply hereinafter), the proportion of Ti becomes relatively large, resulting in a predetermined high temperature hardness and heat resistance. As a result, the progress of wear is accelerated rapidly. On the other hand, when the X value indicating the Al ratio exceeds 0.70, the Ti ratio is relatively decreased, and the high temperature is increased. Since the strength rapidly decreases and as a result, chipping or the like is likely to occur at the cutting edge portion, the X value was determined to be 0.30 to 0.70.

  Further, if the average layer thickness is less than 1 μm, it is insufficient to exhibit its excellent wear resistance over a long period of time, whereas if the average layer thickness exceeds 5 μm, the above-mentioned high viscosity is difficult. In the cutting of the cutting material, chipping is likely to occur at the cutting edge, so the average layer thickness was set to 1 to 5 μm.

(C) Average layer thickness of interlayer adhesion layer If the average layer thickness is less than 0.1 μm, it is not possible to ensure a strong bonding strength between the upper layer and the lower layer, while the average layer thickness is 1.5 μm. If it exceeds 1, the strength of the hard coating layer suddenly decreases at the interlayer adhesion layer portion, which causes the occurrence of chipping. Therefore, the average layer thickness was determined to be 0.1 to 1.5 μm.

(D) V dispersion VO _M layer constituting the content upper layer of the average layer thickness and dispersed metal V of the upper layer has excellent surface slipperiness, as described above workpiece (difficult-to-cut materials) and switching The adhesiveness and reactivity to the powder are extremely low, and this is maintained without changing even when the work material is heated at the time of cutting. Therefore, the (Ti, Al) N layer as the lower layer is heated at the high temperature. This protects against the cut work material and chips and suppresses the occurrence of chipping. However, if the average layer thickness is less than 1 μm, the desired effect cannot be obtained in the above operation, while the average layer thickness is If the thickness exceeds 5 μm and becomes too thick, chipping tends to occur, so the average layer thickness was set to 1 to 5 μm.

Further, the metal V in V dispersed VO _M layer above, by oxidation with a high heating atmosphere during cutting as described above, next VO _M, the wear progress of green bodies produced VO _M of this result consists likewise VO _M There is remarkable inhibitory action, therefore, the V distributed VO _M layer, show compared to VO _M layer consisting only VO _M excellent wear resistance for constituting the matrix, the content of the metal V, matrix a percentage of the total amount of the VO _M layer is less than 0.5 atomic% can not be obtained the desired wear resistance improving effect, whereas the content of the metal V exceeds the same 7 atomic%, the layer itself Since the strength is abruptly reduced and causes chipping, the content is determined to be 0.5 to 7 atomic%.

In the coated carbide tool of the present invention, the lower layer (Ti, Al) N layer constituting the hard coating layer has excellent high-temperature hardness and heat resistance, and excellent high-temperature strength, and as an interlayer adhesion layer. by the V dispersion VO _M layer as an upper layer was firmly adhered joined by VN layer, since the superior surface slipperiness between the workpiece (difficult-to-cut materials) and chips is ensured, in particular viscosity and Even when cutting difficult-to-cut materials such as highly sticky stainless steel, high manganese steel, and mild steel, it exhibits excellent chipping resistance and exhibits excellent wear resistance over a long period of time.

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

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

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

Furthermore, as a cathode electrode (evaporation source) for forming the upper layer of the hard coating layer, first, a metal V powder having an average particle diameter of 0.8 μm is prepared, and this is placed in an oxidizing atmosphere of 10 Pa at a temperature of 1000 ° C. for 1 hour. by heating oxidation treatment under conditions of retention, and VO _M powder, likewise an average particle diameter thereto: a 0.8μm of metal V powder predetermined amount, after 72 hours wet mixed in a ball mill and dried, the pressure of 100MPa Is pressed into a green compact, and the green compact is sintered in a 6 Pa Ar atmosphere at a predetermined temperature within a range of 1200 to 1400 ° C. for 1 hour, thereby allowing the metal V to be predetermined. V dispersion VO _M sintered body containing dispersed at a ratio was prepared.

(A) Next, each of the above-mentioned carbide substrates A-1 to A-10 and B-1 to B-6 was ultrasonically cleaned in acetone and dried, and then in the vapor deposition apparatus shown in FIG. Attached along the outer peripheral portion at a predetermined distance in the radial direction from the central axis on the rotary table, an interlayer adhesion layer forming metal V as the cathode electrode (evaporation source) of the AIP device on one side, and the SP on the other side the upper layer forming V dispersion VO _M sintered body placed opposite a cathode (evaporation source) of the device, further along said rotating table, and each 90 degrees of the metal V and V dispersed VO _M sintered body A Ti-Al alloy for forming a lower layer having a predetermined composition as a cathode electrode (evaporation source) is arranged at a distant position,
(B) First, the inside of the apparatus is evacuated and kept at a vacuum of 0.1 Pa or less, and the inside of the apparatus is heated to 500 ° C. with a heater, and then the carbide substrate that rotates while rotating on the rotary table is set to −1000 V. And applying a current of 100 A between the anode electrode and the Ti-Al alloy for forming the lower layer of the cathode electrode to generate an arc discharge, whereby the surface of the carbide substrate is made to the Ti-Al Bombard washed by alloy and
(C) Introducing nitrogen gas as a reaction gas into the apparatus to form a 4 Pa reaction atmosphere, applying a DC bias voltage of −100 V to a carbide substrate rotating while rotating on the rotary table, and a cathode electrode A current of 120 A is passed between the Ti-Al alloy and the anode electrode to generate an arc discharge, so that the surface of the cemented carbide substrate has a target composition and target layer thickness (Ti, Al) shown in Table 3. ) N layer is deposited as a lower layer of the hard coating layer,
(D) The arc discharge between the cathode electrode and the anode electrode of the Ti—Al alloy for forming the lower layer is stopped, and the atmosphere in the apparatus is kept in a nitrogen atmosphere of 4 Pa, and direct current to the carbide substrate is applied. Under the condition that the bias voltage is also -100 V, a current of 120 A is caused to flow between the metal V of the cathode electrode and the anode electrode to generate arc discharge, so that the VN layer having the target layer thickness shown in Table 3 is also formed. Evaporation formation as an interlayer adhesion layer of hard coating layer,
(E) Arc discharge between the metal V and the anode electrode is stopped, the atmosphere in the vapor deposition apparatus is changed to an Ar atmosphere of 0.5 Pa, and a V-dispersed VO arranged as a cathode electrode (evaporation source) of the SP apparatus Sputtering was started on the _M sintered body under the condition of sputtering output: 3 kW, V dispersion VO having the target layer thickness similarly shown in Table 3 and containing metal V corresponding to the metal V target content ratio. By forming the _M layer as an upper layer of the hard coating layer, the surface-coated carbide throwaway tips (hereinafter referred to as the present invention-coated tips) 1 to 16 as the present invention coated carbide tools are produced, respectively. did.

  For the purpose of comparison, these carbide substrates A-1 to A-10 and B-1 to B-6 were ultrasonically cleaned in acetone and dried, respectively, and the arc ion plate shown in FIG. The Ti-Al alloy having various composition is mounted as a cathode electrode (evaporation source), and first the apparatus is evacuated and kept at a vacuum of 0.1 Pa or less with a heater. After heating the inside of the apparatus to 500 ° C., a DC bias voltage of −1000 V is applied to the carbide substrate, and a current of 100 A is passed between the Ti—Al alloy of the cathode electrode and the anode electrode to cause arc discharge. Then, the surface of the cemented carbide substrate is bombarded with the Ti—Al alloy, and then nitrogen gas is introduced into the apparatus as a reactive gas to form a 4 Pa reaction atmosphere, and a bar is applied to the cemented carbide substrate. An ass voltage was lowered to -100 V to generate an arc discharge between the cathode electrode and the anode electrode of the Ti-Al alloy, and thus the carbide substrates A-1 to A-10 and B-1 to B-6 were used. A conventional surface-coated cemented carbide throw as a conventional coated carbide tool is formed by vapor-depositing a (Ti, Al) N layer having the target composition and target layer thickness shown in Table 4 on each surface as a hard coated layer. Outer chips (hereinafter referred to as conventional coated chips) 1 to 16 were produced, respectively.

Next, in the state where each of the above various coated chips is screwed to the tip of the tool steel tool with a fixing jig, the present coated chips 1 to 16 and the conventional coated chips 1 to 16 are as follows.
Work material: JIS / SUS316 lengthwise equidistant 4 round grooved round bars,
Cutting speed: 300 m / min. ,
Incision: 1.5mm,
Feed: 0.3 mm / rev. ,
Cutting time: 5 minutes
Dry interrupted cutting test of stainless steel under the above conditions (cutting condition A),
Work material: JIS / S15C lengthwise equal length 4 vertical grooved round bars,
Cutting speed: 280 m / min. ,
Incision: 1.5mm,
Feed: 0.35 mm / rev. ,
Cutting time: 5 minutes
Dry interrupted cutting test of mild steel under the above conditions (cutting condition B),
Work material: JIS / SCMnH1 round bar,
Cutting speed: 300 m / min. ,
Incision: 1.5mm,
Feed: 0.25 mm / rev. ,
Cutting time: 10 minutes,
The dry continuous cutting test of high manganese steel under the above conditions (cutting condition C) was performed, 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 [by mass ratio, TiC / WC = 50/50] powder, and 1 .8 μm Co powders were prepared, each of these raw material powders was blended in the composition shown in Table 6, added with wax, ball milled in acetone for 24 hours, dried under reduced pressure, and then shaped into a predetermined shape at a pressure of 100 MPa. The green compacts were press-molded, and these green compacts were heated to a predetermined temperature in the range of 1370 to 1470 ° C. at a rate of temperature increase of 7 ° C./min in a 6 Pa vacuum atmosphere. After holding at temperature for 1 hour, sintering under furnace cooling conditions Three types of sintered carbide rod forming bodies for forming a carbide substrate having diameters of 8 mm, 13 mm, and 26 mm were formed, and further, the three kinds of sintered rods for round bar were ground and shown in Table 6. In combination, the diameter x length of the cutting edge is 6 mm x 13 mm, 10 mm x 22 mm, and 20 mm x 45 mm, respectively, and each is made of a WC-based cemented carbide with a 4-flute square shape with a twist angle of 30 degrees Carbide substrates (end mills) C-1 to C-8 were produced.

Subsequently, the surfaces of these carbide substrates (end mills) C-1 to C-8 were ultrasonically cleaned in acetone and dried, and then charged into the vapor deposition apparatus shown in FIG. Under the same conditions, and a lower layer composed of a (Ti, Al) N layer having a target composition and a target layer thickness shown in Table 7, an interlayer adhesion layer consisting of a VN layer having a target layer thickness also shown in Table 7, further also has a target layer thickness shown in Table 7, and deposited forming a hard coating layer composed of a top layer made of V dispersed VO _M layer dispersed each containing a metal V corresponding to the metal V target content Thus, the surface coated carbide end mills (hereinafter referred to as the present invention coated end mills) 1 to 8 as the present coated carbide tools were produced, respectively.

  For the purpose of comparison, the surfaces of the above-mentioned carbide substrates (end mills) C-1 to C-8 are ultrasonically cleaned in acetone and dried, and the arc ion plating apparatus shown in FIG. The conventional coated carbide tool was deposited and deposited under the same conditions as in Example 1 above, by vapor-depositing a hard coating layer consisting of a (Ti, Al) N layer having the target composition and target layer thickness also shown in Table 7 Conventional surface-coated carbide end mills (hereinafter referred to as conventional coated end mills) 1 to 8 were produced.

Next, of the present invention coated end mills 1-8 and conventional coated end mills 1-8, the present invention coated end mills 1-3 and conventional coated end mills 1-3 are as follows:
Work material-planar dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / S15C plate,
Cutting speed: 80 m / min. ,
Groove depth (cut): 3 mm,
Table feed: 150 mm / min,
About the dry grooving cutting test of mild steel under the conditions of the present invention, the coated end mills 4-6 of the present invention and the conventional coated end mills 4-6,
Work material-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / SUS316 plate material,
Cutting speed: 75 m / min. ,
Groove depth (cut): 5 mm,
Table feed: 120 mm / min,
For the stainless steel wet (using water-soluble cutting oil) grooving test, the present coated end mills 7 and 8 and the conventional coated end mills 7 and 8,
Work material-planar dimensions: 100 mm × 250 mm, thickness: 50 mm JIS / SCMnH1 plate material,
Cutting speed: 60 m / min. ,
Groove depth (cut): 10 mm,
Table feed: 120 mm / min,
The dry grooving test of high manganese steel under the above conditions was conducted, and in each grooving test, the flank wear width of the outer peripheral edge of the cutting edge reached 0.1 mm, which is the standard for the service life. The cutting 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), and 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). 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 made of a WC-base cemented carbide having a two-blade shape with a twist angle of 30 degrees were produced.

Next, the cutting edges of these carbide substrates (drills) D-1 to D-8 are subjected to honing, ultrasonically cleaned in acetone, and dried, and then loaded into the vapor deposition apparatus shown in FIG. Then, under the same conditions as in Example 1, the lower layer composed of the (Ti, Al) N layer having the target composition and target layer thickness shown in Table 8 and the VN layer having the target layer thickness also shown in Table 8 an interlayer adhesion layer comprising, further also has a target layer thickness shown in Table 8, and rigid made up of an upper layer consisting of V dispersed VO _M layer dispersed each containing a metal V corresponding to the metal V target content The surface-coated carbide drills (hereinafter referred to as the present invention-coated drills) 1 to 8 as the present invention coated carbide tools were produced by depositing the coating layer, respectively.

  For comparison purposes, the surfaces of the above-mentioned carbide substrates (drills) D-1 to D-8 are honed, ultrasonically cleaned in acetone, and dried, and the arc shown in FIG. A hard coating layer made of (Ti, Al) N layer having the target composition and target layer thickness shown in Table 8 is also formed by vapor deposition under the same conditions as in Example 1 above while charging in an ion plating apparatus. Thus, conventional surface-coated carbide drills (hereinafter referred to as conventional coated drills) 1 to 8 as conventional coated carbide tools were produced, respectively.

Next, of the present invention coated drills 1 to 8 and the conventional coated drills 1 to 8, the present invention coated drills 1 to 3 and the conventional coated drills 1 to 3 are:
Work material-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / SUS316 plate material,
Cutting speed: 160 m / min. ,
Feed: 0.2mm / rev,
Hole depth: 8mm,
For the wet drilling cutting test of stainless steel under the conditions of the present invention, the present invention coated drills 4-6 and the conventional coated drills 4-6,
Work material-planar dimensions: 100 mm × 250 mm, thickness: 50 mm JIS / SCMnH1 plate material,
Cutting speed: 120 m / min. ,
Feed: 0.25mm / rev,
Hole depth: 16mm,
For the wet drilling cutting test of high manganese steel under the conditions of the present invention, the present invention coated drills 7 and 8 and the conventional coated drills 7 and 8,
Work material-planar dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / S15C plate,
Cutting speed: 100 m / min. ,
Feed: 0.25mm / rev,
Hole depth: 28mm,
Welding drilling test of mild steel under the above conditions, 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) Number was measured. The measurement results are shown in Table 8, respectively.

  (Ti, Al) N constituting the hard coating layer of the present coated chips 1-16, the present coated end mills 1-8, and the present coated drills 1-8 as the present coated carbide tool obtained as a result of this. Composition of the layer (lower layer), and a hard coating layer composed of (Ti, Al) N layers of conventional coated chips 1 to 16, conventional coated end mills 1 to 8, and conventional coated drills 1 to 8 as a conventional coated carbide tool Were measured by an energy dispersive X-ray analysis method using a transmission electron microscope, and showed substantially the same composition as the target composition.

Moreover, as measured by the present invention V dispersed VO _M layer constituting the hard coating layer of the coated cemented carbide tools energy dispersive X-ray analysis of the composition of (upper layer) likewise with a transmission electron microscope, dispersed in the matrix metal V represents substantially the same content as the target content to be further matrix of VO _M is a composition formula, as a main component VO, this _{V 2 O 3, V 2 O} 5, and VO _2, etc. The mixed structure which contains.

  Further, when the average layer thickness of the constituent layers of the hard coating layer was subjected to cross-sectional measurement using a scanning electron microscope, all showed the same average value (average value of five locations) as the target layer thickness.

From the results shown in Tables 3 to 8, all of the coated carbide tools of the present invention have a hard coating layer even when cutting difficult-to-cut materials such as stainless steel, high manganese steel, and mild steel, which are particularly highly viscous and sticky. The V-dispersed VO in which the (Ti, Al) N layer as the lower layer has excellent high-temperature hardness and heat resistance, excellent high-temperature strength, and is firmly adhered to the lower layer by the VN layer as an interlayer adhesion layer _{The M} layer ensures excellent surface slippage between the work material and the chips, so that it exhibits excellent wear resistance over a long period of time without occurrence of chipping. In the conventional coated carbide tool in which the coating layer is composed of a (Ti, Al) N layer, in any cutting of the difficult-to-cut material, the work material (difficult-to-cut material) and chips and the hard coating layer Increased stickiness and reactivity It is clear that chipping occurs at the cutting edge due to the above, and the service life is reached in a relatively short time.

  As described above, the coated carbide tool of the present invention exhibits excellent chipping resistance not only for cutting of general steel and ordinary cast iron, but particularly for cutting of the above difficult-to-cut materials, and for a long time. Since it shows excellent cutting performance, it can fully satisfactorily cope with the FA of the cutting apparatus, labor saving and energy saving of cutting, and cost reduction.

The vapor deposition apparatus used in forming the hard coating layer which comprises this invention coated carbide tool is shown, (a) is a schematic plan view, (b) is a schematic front view. It is a schematic explanatory drawing of a normal arc ion plating apparatus.

Claims (1)

On the surface of the cemented carbide substrate composed of tungsten carbide based cemented carbide or titanium carbonitride based cermet,
(A) It has an average layer thickness of 1 to 5 μm and satisfies the composition formula: (Ti _1-X Al _X ) N (wherein X represents 0.30 to 0.70 in terms of atomic ratio). A lower layer composed of a composite nitride layer of Ti and Al,
(B) an interlayer adhesion layer comprising a vanadium nitride layer having an average layer thickness of 0.1 to 1.5 μm;
(C) having an average layer thickness of 1 to 5 μm, and having a structure in which 0.5 to 7 atomic% of metal vanadium is dispersed and distributed in the vanadium oxide base in a proportion of the total amount with the vanadium oxide. An upper layer comprising a metal vanadium dispersed vanadium oxide layer,
A surface-coated cemented carbide cutting tool that exhibits excellent chipping resistance when a difficult-to-cut material is cut by forming a hard coating layer composed of (a) to (c) above.

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