JP2007038379A - Surface-coated cemented-carbide cutting tool with hard coating layer capable of showing excellent chipping resistance in heavy cutting of 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 capable of showing excellent chipping resistance in heavy cutting of a difficult-to-cut material. <P>SOLUTION: The hard coating layer is formed on the surface of a cemented carbide base body composed of tungsten-carbide-based cemented carbide or titanium-carbonitride-based cermet, the hard coating layer being composed of the following layers (a) to (d): (a) a base body adhered layer which has a mean layer thickness of 0.5 to 2 μm, and is composed of a (Ti, Al)N layer satisfying the following specific composition formula, (Ti<SB>1-Z</SB>Al<SB>Z</SB>)N; (b) a lower layer which has a mean layer thickness of 1 to 5 μm, and is composed of a (Ti, Al, Si)N layer satisfying the following specific composition formula, (Ti<SB>1-(X+Y)</SB>Al<SB>X</SB>Si<SB>Y</SB>)N; (c) an interlayer adhesive layer composed of a vanadium nitride layer having a mean thickness of 1 to 1.5 μm; and (d) an upper layer which has a mean layer thickness of 1 to 5 μm, and is composed of a V-dispersed 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 exhibits excellent chipping resistance with a hard coating layer, especially when cutting difficult-to-cut materials such as stainless steel, high manganese steel, and mild steel under heavy cutting conditions such as high cutting and high feed. The present invention relates to a surface-coated cemented carbide cutting tool (hereinafter referred to as a coated cemented carbide 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 + Y)} Al _X Si _Y ) N (wherein X is 0.40 to 0.70, Y is 0.01 to 0.20 in atomic ratio),
Coated carbide tool formed by physical vapor deposition of a hard coating layer composed of a composite nitride of Ti, Al, and Si [hereinafter referred to as (Ti, Al, Si) N] layer satisfying the following conditions with an average layer thickness of 1 to 15 μm The (Ti, Al, Si) N layer, which is a hard coating layer of the above-mentioned coated carbide tool, has high-temperature strength by the component Ti, high-temperature hardness and heat resistance by the same Al, Furthermore, since it has been further improved in heat resistance due to the inclusion of Si, it can also exhibit excellent cutting performance when used for continuous cutting and intermittent cutting of various general steels and ordinary cast iron. Are known.

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, an arc discharge is generated between the anode electrode and a cathode electrode (evaporation source) on which a Ti—Al—Si alloy having a predetermined composition is set, for example, at a current of 90 A, while being heated to a temperature of 500 ° C. At the same time, nitrogen gas is introduced into the apparatus as a reaction gas to form a reaction atmosphere of, for example, 2 Pa. On the other hand, the carbide substrate is applied to the surface of the carbide substrate under a condition that a bias voltage of, for example, −100 V is applied. It is also known that it is produced by vapor-depositing a hard coating layer composed of the (Ti, Al, Si) N layer.
Japanese Patent No. 2793773

  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 material type of the 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 stainless steel, high manganese steel, mild steel, etc., which have high chip viscosity and are easy to weld to the tool surface. When cutting a difficult-to-cut material (work material) under heavy cutting conditions such as high cutting and high feed, where the load is locally applied to the cutting edge, the work material is generated by the heat generated during cutting. And chips are hot When heated, the viscosity further increases, and as a result, not only the adhesion and reactivity to the hard coating layer surface further increase, but also the (Ti, Al, Si) N layer which is a hard coating layer Since the adhesion to the surface of the cemented carbide substrate is not sufficient, in the cutting of the difficult-to-cut material under heavy cutting conditions, the occurrence of chipping (slight chipping) at the cutting edge portion increases rapidly, which is relatively The current situation is that the service life is reached in a short time.

In view of the above, the present inventors have demonstrated excellent chipping resistance with a hard coating layer, particularly when cutting difficult-to-cut materials under heavy cutting conditions such as high cutting and high feed. As a result of conducting research focusing on the above-mentioned conventional coated carbide tools,
(A) A (Ti, Al, Si) N layer, which is a hard coating layer of the above conventional coated carbide tool, is formed with an average layer thickness of 1 to 5 μm as a lower layer, and vanadium oxide (hereinafter referred to as an upper layer) thereon. , VO _M, where _M represents a change value of the relative content ratio of oxygen to vanadium, and the atomic ratio indicates VO, V ₂ O ₃ , V ₂ O ₅ , VO _2, etc.) by forming an average layer thickness of 5 .mu.m, the VO _M layer is excellent surface slipperiness, cutting edge even when the result workpiece by heat generated during cutting (difficult-to-cut materials) and its cutting scraps is high temperature heating Excellent slidability is always ensured between the rake face and the flank face and the cutting edge ridge line where both the surfaces intersect, and the work material and chips, and the surface of the work material and the cutting edges of the chips. The lower layer is significantly reduced in tackiness and reactivity with respect to ( i, Al, Si) N-layer because it sufficiently protect, (Ti, Al, Si) 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, it is the V dispersion VO _M layer and the lower layer is an upper layer (Ti, Al, Si) adhesion to the N layer is not sufficient, the interlayer of especially when subjected to intermittent cutting Although easy adhesion insufficient chipping caused by the V dispersed VO _M layer and (Ti, Al, Si) between the N layer vanadium nitride (hereinafter indicated by VN) layer 0.1-1. When interposing an average layer thickness of 5 [mu] m, the VN layer the V dispersed VO _M layer and (Ti, Al, Si) because it is firmly adhered with any of the N layer, adhesion with excellent in both of these layers To be secured.

(D) Further, as described above, the adhesion of the (Ti, Al, Si) N layer to the carbide substrate surface is not sufficiently satisfactory for cutting under difficult cutting conditions under heavy cutting conditions. A composite nitride layer of Ti and Al [hereinafter referred to as (Ti, Al) N] layer is composed of a composition formula: (Ti ₁ -Z Al _Z ) N (wherein Z is 0.30-0. 70) and with an average layer thickness of 0.5 to 2 μm, the (Ti, Al) N layer is either the surface of the carbide substrate or the (Ti, Al, Si) N layer. Since both are firmly adhered, excellent adhesion between them should be ensured.

(E) The hard coating layer constituted by the above (a) to (d) 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 Ti-Al-Si alloy having a predetermined composition as a cathode electrode (vapor source) of the AIP device on one side of 90 degrees away from each of the metal V and V dispersed VO _M sintered body, other Similarly, a vapor deposition apparatus in which a Ti-Al alloy having a predetermined composition is disposed as a cathode electrode (evaporation source) of the AIP apparatus, and the outer periphery is positioned at a predetermined distance in the radial direction from the central axis on the rotary table of the apparatus. For the purpose of mounting a plurality of carbide substrates in a ring shape along the section, rotating the rotary table with the atmosphere inside the apparatus as a nitrogen atmosphere in this state, and uniformizing the thickness of the hard coating layer formed by vapor deposition While the carbide substrate itself rotates, basically, first, arc discharge is generated between the cathode electrode (evaporation source) of the Ti-Al alloy and the anode electrode, and the substrate adheres to the surface of the carbide substrate. After depositing a (Ti, Al) N layer as an average layer thickness of 0.5 to 2 μm, the arc discharge between the cathode electrode (evaporation source) and the anode electrode of the Ti—Al alloy is stopped and pulled. Continued While maintaining the atmosphere in the apparatus in a nitrogen atmosphere, an arc discharge is generated between the cathode electrode (evaporation source) and the anode electrode of the Ti—Al—Si alloy to form (Ti, Al, Si) as a lower layer. ) N layer is deposited with an average layer thickness of 1 to 5 μm, and then the arc discharge between the cathode electrode (evaporation source) and anode electrode of the Ti—Al—Si alloy is stopped, and the atmosphere in the apparatus is also a nitrogen atmosphere An arc discharge is generated between the metal V, which is the cathode electrode (evaporation source) of the AIP device, and the anode electrode, and the average VN layer is 0.1 to 1.5 μm as an interlayer adhesion layer. was deposited in a layer thickness, the weight of the atmosphere in the deposition apparatus with the Ar atmosphere, the VN layer by performing sputtering of V dispersion VO _M sintered body was disposed as the cathode electrode of the SP device (evaporation source) Sleep can be formed by depositing a V dispersion VO _M layer with an average layer thickness 1~5μm as an upper layer.

(F) A coated carbide tool formed by vapor-depositing a hard coating layer composed of the above-mentioned substrate adhesion layer, lower layer, interlayer adhesion layer, and upper layer is made of stainless steel or high manganese that has particularly high viscosity and adhesion. Even when cutting difficult-to-cut materials such as steel and mild steel under heavy cutting conditions such as high cutting with high load and high feed, it is firmly bonded to the surface of the carbide substrate through the substrate adhesion layer. The (Ti, Al, Si) N layer, which is the lower layer, has excellent high temperature hardness and heat resistance, and excellent high temperature strength, and is superior to the lower layer by interposing the VN layer as an interlayer adhesion layer. by the action of V dispersion VO _M layer adhesion bonding property is ensured, for the flame excellent surface slipperiness between the work material and chips is ensured, the flame-cut materials and cutting edge surfaces of the chips Cut off with significantly reduced stickiness and reactivity Since machining is performed, chipping is not generated at the cutting edge, and excellent wear resistance is exhibited over a long period of time.
The research results shown in (a) to (f) above were obtained.

This invention was made based on the above research results, and on the surface of the carbide substrate,
(A) having an average layer thickness of 0.5-2 μm, and
Composition formula: (Ti ₁ -Z Al _Z ) N (however, in atomic ratio, Z represents 0.30 to 0.70),
A substrate adhesion layer comprising a (Ti, Al) N layer satisfying
(B) having an average layer thickness of 1-5 μm, and
Composition formula: (Ti _{1- (X + Y)} Al _X Si _Y ) N (wherein, X is 0.40 to 0.70, Y is 0.01 to 0.20 in atomic ratio),
A lower layer made of a (Ti, Al, Si) N layer satisfying
(C) an interlayer adhesion layer comprising a VN layer having an average layer thickness of 0.1 to 1.5 μm;
(D) 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;
What is characterized by a coated carbide tool that exhibits excellent chipping resistance in heavy cutting of difficult-to-cut materials, formed by forming a hard coating layer composed of (a) to (d) above. It is.

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) Composition of substrate adhesion layer and average layer thickness In the (Ti, Al, Si) N layer as the lower layer, the Si component further improves the heat resistance of the layer itself, thereby contributing to the improvement of the wear resistance. However, it is a component that lowers the adhesion to the surface of the cemented carbide substrate. Therefore, the substrate adhesion layer is composed of a (Ti, Al) N layer, and the effect of Ti that is a component of the substrate is cemented carbide. It is intended to ensure strong adhesion to both the substrate surface and the lower layer, while containing the same Al component improves the high-temperature hardness and heat resistance of the layer itself as in the lower layer. , Which contributes to the improvement of the wear resistance of the hard coating layer, but when the Z value indicating the proportion of Al is less than 0.30 in terms of the proportion of the total amount with Ti (atomic ratio, the same applies hereinafter), High temperature hardness and heat resistance can be secured. Scratches cause a decrease in wear resistance. On the other hand, if the Z value indicating the Al ratio exceeds 0.70, the Ti ratio is relatively less than 0.30, and the surface of the carbide substrate and the lower part are reduced. Since the desired excellent adhesion between the layers cannot be ensured, the Z value is set to 0.30 to 0.70.
Also, if the average layer thickness is less than 0.5 μm, the desired excellent adhesion cannot be secured between the surface of the cemented carbide substrate and the lower layer, while if the average layer thickness exceeds 2 μm, the above viscosity Since heavy cutting of a highly difficult-to-cut material causes a decrease in the wear resistance of the hard coating layer, the average layer thickness is set to 0.5 to 2 μm.

(B) Lower layer composition and average layer thickness The (Ti, Al, Si) N layer constituting the lower layer has high-temperature hardness and heat resistance for the Al component, high-temperature strength for the Ti component, and Si component. Has the effect of further improving the heat resistance, but when the X value indicating the proportion of Al is less than 0.40 in terms of the proportion of the total amount of Ti and Si (atomic ratio, the same shall apply hereinafter), relatively Ti The ratio becomes too high to ensure the predetermined high temperature hardness and heat resistance. As a result, the progress of wear is accelerated rapidly, while the X value indicating the Al ratio exceeds 0.70. Then, the ratio of Ti becomes relatively small, and the high-temperature strength sharply decreases. As a result, chipping or the like is likely to occur in the cutting edge portion. Therefore, the X value is set to 0.40 to 0.70. Further, the Y value indicating the proportion of Si is T If the ratio of i and Al in the total amount is less than 0.01, the desired heat resistance improvement effect cannot be obtained. On the other hand, if the Y value exceeds 0.20, the high-temperature strength suddenly decreases. The Y value was determined to be 0.01-0.20.
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 change even when the work material is heated at high temperature during cutting, so the (Ti, Al, Si) N layer as the lower layer is Protects from work material and chips heated at high temperature, and exerts an action of suppressing the occurrence of chipping, but if the average layer thickness is less than 1 μm, the desired effect cannot be obtained in the action, while the average If the layer thickness exceeds 5 μm and becomes too thick, chipping is likely to occur. Therefore, 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, Si) N layer constituting the hard coating layer is firmly attached to the surface of the carbide substrate by the action of the (Ti, Al) N layer as the substrate adhesion layer. in close contact bonding, the excellent high-temperature hardness and heat resistance, further has excellent high-temperature strength, and V dispersed VO _M layer as an upper layer was firmly adhered joined by VN layer as the interlayer adhesion layer, Excellent surface slippage is ensured between the work material (difficult-to-cut material) and chips, so that high-viscosity materials such as highly viscous and sticky stainless steel, high manganese steel, and even mild steel Even in heavy-duty machining with a load, 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-Si alloy for forming a lower layer having a predetermined composition as a cathode electrode (evaporation source) of an AIP device on one side of the remote position, and a predetermined composition as a cathode electrode (evaporation source) of the AIP device on the other side Substrate having Place the Ti-Al alloy for adhesive layer formation,
(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 substrate adhesion layer of the cathode electrode to generate an arc discharge, thereby causing the surface of the carbide substrate to adhere to the Ti— Bombarded with Al alloy,
(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) shown in Tables 3 and 4. , Al) N layer is formed by vapor deposition as a substrate adhesion layer of a hard coating layer,
(D) The arc discharge between the cathode electrode and the anode electrode of the Ti—Al alloy for forming the substrate adhesion layer is stopped, the atmosphere in the apparatus is maintained in the same nitrogen atmosphere of 4 Pa, and direct current to the carbide substrate is maintained. Similarly, with the bias voltage kept at −100 V, a current of 120 A is passed between the Ti—Al—Si alloy of the cathode electrode and the anode electrode to generate an arc discharge. (Ti, Al, Si) N layer having a target composition and target layer thickness shown in 3 and 4 is deposited as a lower layer of the hard coating layer,
(E) The arc discharge between the cathode electrode and the anode electrode of the Ti—Al—Si alloy for forming the lower layer is stopped, and the atmosphere in the apparatus is similarly maintained in a 4 Pa nitrogen atmosphere, and to the carbide substrate. Similarly, under the condition that the DC bias voltage is -100 V, a current of 120 A is passed between the metal V of the cathode electrode and the anode electrode to generate arc discharge, and the target layer thicknesses shown in Tables 3 and 4 are also shown. VN layer is deposited as an interlayer adhesion layer of a hard coating layer,
(F) The 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 the V-dispersed VO arranged as the 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 having the target layer thickness shown in Tables 3 and 4 and containing metal V corresponding to the metal V target content ratio in a dispersed manner. by depositing form a dispersion VO _M layer as the upper layer of the hard coating layer, the present invention coated carbide tool as the present invention the surface coating cemented carbide indexable (hereinafter, referred to as the present invention coated chip) 1 to 16 Each was manufactured.

  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-Si alloy having various component compositions as a cathode electrode (evaporation source) is mounted, and first the apparatus is evacuated and kept at a vacuum of 0.1 Pa or less, After heating the inside of the apparatus to 500 ° C. with a heater, a DC bias voltage of −1000 V is applied to the cemented carbide substrate, and a current of 100 A is passed between the Ti—Al—Si alloy of the cathode electrode and the anode electrode. Then, arc discharge is generated, and the surface of the carbide substrate is bombarded with the Ti—Al—Si alloy, and then nitrogen gas is introduced into the apparatus as a reaction gas to form a reaction atmosphere of 4 Pa. The bias voltage applied to the substrate is lowered to −100 V, and arc discharge is generated between the cathode electrode and the anode electrode of the Ti—Al—Si alloy, so that the carbide substrates A-1 to A-10 and B A conventional coated carbide is formed by vapor-depositing a (Ti, Al, Si) N layer having the target composition and target thickness shown in Tables 5 and 6 on each surface of -1 to B-6 as a hard coating layer. Conventional surface-coated carbide throwaway tips (hereinafter referred to as conventional coated tips) 1 to 16 as tools were manufactured, 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: 280 m / min. ,
Cutting depth: 2mm,
Feed: 0.3 mm / rev. ,
Cutting time: 5 minutes
Stainless steel dry interrupted cutting test (normal cutting depth is 1.2 mm)
Work material: JIS / S15C round bar,
Cutting speed: 320 m / min. ,
Incision: 2.5mm,
Feed: 0.25 mm / rev. ,
Cutting time: 10 minutes,
Dry continuous high-cut cutting test of mild steel under the above conditions (cutting condition B) (normal cutting is 1.5 mm),
Work material: JIS · SCMnH1 lengthwise equidistant four round grooved round bars,
Cutting speed: 280 m / min. ,
Incision: 1.5mm,
Feed: 0.5 mm / rev. ,
Cutting time: 5 minutes
The dry interrupted high-feed cutting test (normal feed is 0.3 mm / rev.) Of high manganese steel under the above conditions (cutting condition C). It was measured. The measurement results are shown in Table 7.

As raw material powders, medium coarse WC powder having an average particle diameter of 5.5 μm, fine WC powder of 0.8 μm, TaC powder of 1.3 μm, NbC powder of 1.2 μm, ZrC of 1.2 μm Powder, 2.3 μm Cr ₃ C ₂ powder, 1.5 μm VC powder, 1.0 μm (Ti, W) C [by mass ratio, TiC / WC = 50/50] powder, and 1 Prepare 8 μm Co powder, mix these raw material powders with the composition shown in Table 8, add wax, ball mill in acetone for 24 hours, dry under reduced pressure, and press at a pressure of 100 MPa. The green compacts were press-molded, and these green compacts were heated to a predetermined temperature in the range of 1370 to 1470 ° C. at a rate of temperature increase of 7 ° C./min in a 6 Pa vacuum atmosphere. After holding at temperature for 1 hour, sintering under furnace cooling conditions 3 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 types of sintered rods for round bar were subjected to grinding, as shown in Table 7. Made of WC-base cemented carbide with a combination of 4 blade square shape with diameter and length of 6mm × 13mm, 10mm × 22mm, and 20mm × 45mm respectively, and 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 as in Table 9, the substrate composition layer composed of the (Ti, Al) N layer having the target composition and the target layer thickness shown in Table 9 and the lower layer composed of the (Ti, Al, Si) N layer, an interlayer adhesion layer made of VN layer of the target layer thicknesses shown, further also has a target layer thickness shown in Table 9, and V dispersed VO _M layer metal V corresponding to the metal V target content dispersed respectively containing The surface coating carbide end mills (hereinafter referred to as the present invention coated end mills) 1 to 8 as the coated carbide tools of the present invention are produced by vapor-depositing a hard coating layer composed of an upper layer made of did.

  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. In the same conditions as in Example 1 above, a hard coating layer consisting of a (Ti, Al, Si) N layer having the target composition and target layer thickness also shown in Table 10 is vapor-deposited. Conventional surface-coated carbide end mills (hereinafter referred to as conventional coated end mills) 1 to 8 as hard tools were produced, respectively.

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-Plane dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / SUS316 plate material,
Cutting speed: 80 m / min. ,
Groove depth (cut): 5 mm,
Table feed: 120 mm / min,
For the stainless steel dry-type high-groove grooving test (normal groove depth is 3 mm), the coated end mills 4-6 of the present invention and the conventional coated end mills 4-6,
Work material-planar dimensions: 100 mm × 250 mm, thickness: 50 mm JIS / SCMnH1 plate material,
Cutting speed: 75 m / min. ,
Groove depth (cut): 5 mm,
Table feed: 250 mm / min,
For high manganese steel dry high feed groove cutting test (normal table feed is 150 mm / min), coated end mills 7 and 8 of the present invention and conventional coated end mills 7 and 8
Work material-planar dimensions: 100 mm x 250 mm, thickness: 50 mm JIS / S15C plate,
Cutting speed: 70 m / min. ,
Groove depth (cut): 16 mm,
Table feed: 150 mm / min,
Each of the dry high-groove grooving tests (normal groove depth is 10 mm) of mild steel under the above conditions, the flank wear width of the outer peripheral edge of the cutting edge is the guideline for service life The cutting groove length up to 0.1 mm was measured. The measurement results are shown in Tables 9 and 10, 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 substrate adhesion layer composed of the (Ti, Al) N layer having the target composition and the target layer thickness shown in Table 11 and the lower layer composed of the (Ti, Al, Si) N layer. And an interlayer adhesion layer composed of a VN layer having the target layer thickness shown in Table 11 and a metal V having the target layer thickness shown in Table 11 and corresponding to the metal V target content ratio. the V dispersed VO by depositing form a hard coating layer composed of a _M consisting layer upper layer, the present invention present invention surface coating cemented carbide drills of the coated cemented carbide (hereinafter, referred to as the present invention coated drills) 1 to 8 were produced.

  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 comprising a (Ti, Al, Si) N layer having the target composition and target layer thickness similarly shown in Table 12 is formed by vapor deposition under the same conditions as in Example 1 above. Thus, conventional surface coated carbide drills (hereinafter referred to as conventional coated drills) 1 to 8 as conventional coated carbide tools were manufactured, 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: 120 m / min. ,
Feed: 0.4mm / rev,
Hole depth: 8mm,
For the stainless steel wet high feed drilling cutting test (normal feed is 0.25 mm / rev), 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: 100 m / min. ,
Feed: 0.5mm / rev,
Hole depth: 16mm,
For the high manganese steel wet high feed drilling test under normal conditions (normal feed is 0.3 mm / rev), 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: 90 m / min. ,
Feed: 0.55mm / rev,
Hole depth: 28mm,
Wet and high-drilling drilling test of mild steel under normal conditions (normal feed is 0.35mm / rev), and any wet high-speed drilling test (using water-soluble cutting oil) The number of drilling processes until the flank wear width reached 0.3 mm was measured. The measurement results are shown in Tables 11 and 12, 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 layer (base adhesion layer) and (Ti, Al, Si) N layer (lower layer), conventional coated tips 1-16 as conventional coated carbide tools, conventional coated end mills 1-8, and conventional coated drill 1 When the composition of the hard coating layer consisting of (Ti, Al, Si) N layers of ~ 8 was measured by energy dispersive X-ray analysis using a transmission electron microscope, the composition was substantially the same as the target composition. Indicated.
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. Shows the mixed structure contained.

  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 12, all of the coated carbide tools of the present invention have high viscosities such as high cutting and high feed of difficult-to-cut materials such as stainless steel, high manganese steel, and mild steel, which are particularly highly viscous and sticky. Even in cutting under cutting conditions, the (Ti, Al, Si) N layer, which is the lower layer of the hard coating layer, is tightly bonded to the surface of the carbide substrate by the (Ti, Al) N layer, which is the substrate adhesion layer. in, excellent high-temperature hardness and heat resistance, further has excellent high-temperature strength, and by V dispersed VO _M layer firmly adhered to the lower layer by VN layer as an interlayer adhesion layer, wherein the workpiece and chips Excellent surface slip is ensured between the two, and the chipping does not occur and the wear resistance is excellent for a long time, whereas the hard coating layer is (Ti, Al, Si) N. Conventional coated carbide construction composed of layers In the tool, in both heavy cutting of the difficult-to-cut material, the adhesiveness and reactivity between the work material (hard-to-cut material) and chips and the hard coating layer are further increased, and the hard coating layer Since the adhesion to the surface of the cemented carbide substrate is insufficient, it is apparent that chipping occurs at the cutting edge 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 heavy cutting of the above difficult-to-cut materials, and for a long time. Since it shows excellent cutting performance over time, it can sufficiently satisfactorily cope with the FA of the cutting apparatus, labor saving and energy saving of the cutting work, and further 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) having an average layer thickness of 0.5-2 μm, and
Composition formula: (Ti ₁ -Z Al _Z ) N (however, in atomic ratio, Z represents 0.30 to 0.70),
A substrate adhesion layer comprising a composite nitride layer of Ti and Al satisfying
(B) having an average layer thickness of 1-5 μm, and
Composition formula: (Ti _{1- (X + Y)} Al _X Si _Y ) N (wherein, X is 0.40 to 0.70, Y is 0.01 to 0.20 in atomic ratio),
A lower layer composed of a composite nitride layer of Ti, Al, and Si that satisfies
(C) an interlayer adhesion layer comprising a vanadium nitride layer having an average layer thickness of 0.1 to 1.5 μm;
(D) It has an average layer thickness of 1 to 5 μm, and has 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 in heavy cutting of difficult-to-cut materials, formed by forming a hard coating layer composed of the above (a) to (d).

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