JP4530138B2 - Surface coated cemented carbide cutting tool with excellent wear resistance due to lubricated amorphous carbon coating - Google Patents

Description

  This invention has excellent resistance to lubrication of amorphous carbon-based coatings even when cutting various steels and cast irons and other non-ferrous materials such as Al alloys and Cu alloys, especially at high speeds. The present invention relates to a surface-coated cemented carbide cutting tool that exhibits wearability (hereinafter referred to as a coated cemented carbide tool).

  In general, as a coated carbide tool, a throw-away tool that is detachably attached to the tip of a cutting tool for turning and planing of various steel and cast iron and other non-ferrous materials such as Al alloy and Cu alloy. There are drills and miniature drills used for inserts, drilling and cutting, and solid type end mills used for chamfering, grooving, shoulder processing, etc. A slow-away end mill tool that performs a cutting process in the same manner as an end mill is known.

In addition, as the above coated carbide tool,
(A) on the surface of a cemented carbide substrate made of tungsten carbide (hereinafter referred to as WC) based cemented carbide or titanium carbonitride (hereinafter referred to as TiCN) cermet;
(B) Nitriding formed in a sputtering apparatus using a Ti target as a cathode electrode (evaporation source) in a reaction atmosphere consisting of a mixed gas of nitrogen and Ar, or a mixed gas of hydrocarbon decomposition gas and nitrogen and Ar Through a tight junction layer consisting of either or both of a titanium (hereinafter referred to as TiN) layer and a titanium carbonitride (hereinafter referred to as TiCN) layer, and having an average layer thickness of 0.1 to 3 μm,
(C) Using a WC target as a cathode electrode (evaporation source) in a sputtering apparatus, formed in a reaction atmosphere composed of a hydrocarbon decomposition gas and an Ar mixed gas, and measured with an Auger spectroscopic analysis apparatus,
W: 5 to 20 atomic%,
A coated carbide tool is known which has a composition comprising carbon and the remainder consisting of carbon and inevitable impurities, and is formed by vapor deposition of a lubricious amorphous carbon-based film having an average layer thickness of 1 to 13 μm. Yes.

Further, the conventional coated carbide tool is, for example, a schematic plan view in FIG. 3A and a schematic front view in FIG. 3B, and a sputtering apparatus in which the cathode electrode (evaporation source) is a Ti target, The above carbide substrate is inserted into a vapor deposition apparatus having a cathode electrode (evaporation source) equipped with a sputtering apparatus for a WC target, and the inside of the apparatus is heated to a temperature of, for example, 300 ° C. with a heater. As an example, nitrogen and Ar are introduced at a rate of, for example, nitrogen flow rate: 200 sccm and Ar flow rate: 300 sccm. For example, a mixed gas of nitrogen and Ar of 1 Pa, or C ₂ H ₂ (hydrocarbon), nitrogen and Ar, for example, C ₂ H ₂ flow rate: 40 sccm, nitrogen flow rate: 200 sccm, Ar flow rate: 300 sccm were introduced at the same rate, 1 Pa of C ₂ H ₂ decomposition gas, nitrogen and Ar A sputtering atmosphere with an output of 12 kW (frequency: 40 kHz) is applied to the cathode electrode (evaporation source) of the Ti target, while a bias voltage of, for example, −100 V is applied to the cemented carbide substrate. A glow discharge is generated under the applied conditions, and a close contact bonding layer made of either or both of a TiN layer and a TiCN layer having a predetermined thickness is formed on the surface of the cemented carbide substrate. In a state of 200 ° C., a hydrocarbon such as C ₂ H ₂ and Ar are introduced at a rate of C ₂ H ₂ flow rate: 40 to 80 sccm and Ar flow rate: 250 sccm, and the mixed gas of nitrogen and Ar, or Change the reaction atmosphere consisting of a mixed gas of methane decomposition gas and nitrogen and Ar, for example, to a reaction atmosphere consisting of 1 Pa hydrocarbon decomposition gas and Ar mixed gas, For example, under the condition that the bias voltage applied to the cemented carbide substrate is −20 V and the sputtering power of 4 to 6 kW (frequency: 40 kHz) is applied to the cathode electrode (evaporation source) of the WC target, It is also known to be produced by vapor deposition of a lubricious amorphous carbon-based film having a predetermined layer thickness.
Japanese Patent Laid-Open No. 07-164211 Japanese translation of PCT publication No. 2002-513087

  In recent years, the performance of cutting machines has been remarkable. On the other hand, there is a strong demand for labor saving and energy saving and further cost reduction for cutting. With this trend, cutting tends to be faster. In coated carbide tools, there is no problem when they are used under normal cutting conditions. However, especially when cutting is performed at high speed, the wear of the lubricious amorphous carbon coating is remarkably increased. The current situation is that the service life is reached quickly and in a relatively short time.

In view of the above, the present inventors conducted research in order to develop a coated carbide tool that exhibits excellent wear resistance with a lubricious amorphous carbon-based film particularly in high-speed cutting. result,
(A) Sputtering in the vapor deposition apparatus shown in the schematic plan view and schematic front view in FIGS. 2 (a) and 2 (b), that is, the conventional lubrication amorphous carbon-based film formation vapor deposition apparatus shown in FIG. A vapor deposition apparatus in which an electromagnetic coil is provided in each of the apparatuses to form a magnetron sputtering apparatus, a magnetic field is formed by the electromagnetic coil, and a magnetic flux density in a mounting portion of the carbide substrate is set to 100 to 300 G (Gauss). In the state in which the heating temperature is 300 to 500 ° C. and the reaction gas in the apparatus is, for example, hydrocarbon such as C ₂ H ₂ , nitrogen and Ar, preferably C ₂ H ₂ flow rate: 25 to 100 sccm, nitrogen flow rate: 200～300Sccm, Ar flow rate: introduced at a rate of 150～250Sccm, the reaction atmosphere, for example 1Pa decomposition of _C 2 _{H 2} of For example, the cathode power (evaporation source) of the WC target of both of the magnetron sputtering apparatuses has a sputtering power of 1 to 3 kW (frequency: 40 kHz). For example, when a lubricous amorphous carbon-based film is formed under a condition in which sputtering power of output: 3 to 8 kW (frequency: 40 kHz) is simultaneously applied, the resulting lubricous amorphous carbon-based film is As shown in the schematic diagram of FIG. 1, the result of the observation of the structure by a transmission electron microscope is as follows. Fine particles of crystalline titanium carbonitride-based compound [hereinafter referred to as “crystalline Ti (C, N ) System compound fine particles ”have a distributed structure.

(B) Flow rates of hydrocarbon, nitrogen and Ar as reaction gases introduced into the vapor deposition apparatus when forming the lubricious amorphous carbon-based film of (a) above, and the WC target of the magnetron sputtering apparatus And adjusting the sputtering power applied to the Ti target, the lubricating amorphous carbon-based coating is measured with an Auger spectroscopic analyzer,
W: 5 to 20 atomic%,
Ti: 5 to 20 atomic%,
Nitrogen: 0.5-18 atomic%,
And the rest of the resulting lubricating amorphous carbon-based coating has a dispersion distribution effect of crystalline Ti (C, N) -based fine particles, and The hardness is remarkably improved by the fine graining effect during the magnetic field film formation by the electromagnetic coil. Therefore, the coated carbide tool formed with this lubricous amorphous carbon-based film is based on the W component. Combined with the strength improvement effect, even at high-speed cutting, there is no chipping (small chipping) at the cutting edge, and it will exhibit even better wear resistance over a long period of time.
The research results shown in (a) and (b) above were obtained.

This invention was made based on the above research results,
(A) On the surface of a cemented carbide substrate made of a WC-based cemented carbide or TiCN cermet,
(B) In a magnetron sputtering apparatus, a Ti target is used as a cathode electrode (evaporation source), and a film is formed in a magnetic field in a reaction atmosphere composed of a mixed gas of nitrogen and Ar, or a mixed gas of hydrocarbon decomposition gas and nitrogen and Ar. Through a tight junction layer comprising either or both of a TiN layer and a TiCN layer and having an average layer thickness of 0.1 to 3 μm,
(C) Similarly, in a magnetron sputtering apparatus, a WC target and a Ti target are used as a cathode electrode (evaporation source), and a film is formed in a magnetic field in a reaction atmosphere composed of a hydrocarbon decomposition gas and a mixed gas of nitrogen and Ar. Measured with a spectroscopic analyzer,
W: 5 to 20 atomic%,
Ti: 5 to 20 atomic%,
Nitrogen: 0.5-18 atomic%,
And the remainder of the composition is composed of carbon and inevitable impurities, and the crystalline Ti (C, N) compound fine particles are dispersed and distributed on the base of the carbon-based amorphous body by observation with a transmission electron microscope. Demonstrated by depositing a lubricious amorphous carbon-based film having a texture and an average layer thickness of 1 to 13 μm, and exhibiting excellent wear resistance, especially in high-speed cutting It is characterized by the coated carbide tool.

Next, in the coated carbide tool of the present invention, the reason why the tight bonding layer and the lubricious amorphous carbon-based coating constituting the same are limited as described above will be described.
(A) Average layer thickness of tight junction layer The tight junction layer consisting of either or both of the TiN layer and the TiCN layer is between the cemented carbide substrate and the lubricious amorphous carbon-based coating, and firmly adheres to both. Bonding and further adhesion to the cemented carbide substrate is further improved by film formation in a magnetic field, but if the average layer thickness is less than 0.1 μm, the desired excellent adhesion can be secured. On the other hand, if the average layer thickness exceeds 3 μm, thermoplastic deformation is likely to occur particularly at high speed cutting, which causes chipping in the lubricous amorphous carbon-based coating. It was determined to be 1 to 3 μm.

(B) W content of lubricious amorphous carbon-based coating W component forms the base of the above-mentioned lubricous amorphous carbon-based coating and has the effect of improving the strength of the coating. However, if the content is less than 5 atomic%, the desired high strength cannot be ensured. On the other hand, if the content exceeds 20 atomic%, the lubricity decreases rapidly. %.

(C) Ti and N contents of lubricating amorphous carbon-based film Ti component, N component, and C (carbon) component are combined under film formation of magnetic field, and crystalline Ti (C, N) is formed in the film. ) Present as system compound fine particles, and has the effect of remarkably improving the hardness of the coating. However, when the content of Ti component is less than 5 atomic% and the N component is less than 0.5 atomic%, Ti is contained in the coating. The proportion present as (C, N) -based fine particles becomes too small to ensure the desired high hardness, while its content exceeds 20 atomic% for the Ti component and 18 atomic% for the N component. Since the strength and the lubricity are drastically lowered, the contents are determined as Ti: 5 to 20 atomic% and N: 0.5 to 18 atomic%, respectively.

(D) Average layer thickness of lubricating amorphous carbon-based coating If the average layer thickness is less than 1 μm, the desired lubricity and wear resistance effect cannot be ensured, while the average layer thickness exceeds 13 μm. Then, since chipping is likely to occur at the cutting edge portion, the average layer thickness was determined to be 1 to 13 μm.

  The coated cemented carbide tool of the present invention is dispersed in a state in which the hardness of the lubricating amorphous carbon-based film constituting the same is made ultrafine by magnetic film formation on the carbon-based amorphous body. Combined with the fact that the crystalline Ti (C, N) -based compound fine particles that are distributed are significantly improved, and the base of the carbon-based amorphous body has high strength due to the action of the W component. It exhibits excellent wear resistance over a long period of time without occurrence of chipping by high-speed cutting of various steels and steel materials such as cast iron, and Al alloys and Cu alloys.

  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 0.8 to 3 μm are prepared. Compounded in the composition shown in Table 1, wet mixed in a ball mill for 84 hours, dried, and then pressed into a green compact at a pressure of 100 MPa. The green compact was heated to 1400 ° C. in a vacuum of 6 Pa. Sintered under the condition of holding for 1 hour to produce a carbide substrate material for cutting carbon steel and a carbide substrate material for cutting Al alloy and Cu alloy, both of which are made of WC-based cemented carbide. The hard base material is subjected to a honing process of R: 0.03 on the cutting edge portion to obtain carbide bases A-1 to A-10 having a chip shape of ISO standard TNMG160408, and the Al alloy and Cu alloy cutting. Super The base material was cemented carbide substrate A-1'~A-10 'having a tip shape of ISO standard · TEGX160304R subjected to abrasive machining.

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, blend these raw material powders into the composition shown in Table 2, wet-mix for 84 hours with a ball mill, dry, and press-mold into green compact at 100 MPa pressure Then, this green compact was sintered in a nitrogen atmosphere of 2 kPa at a temperature of 1500 ° C. for 1 hour, both of which were made of a carbide substrate carbide substrate made of TiCN cermet, an Al alloy and a Cu alloy. A carbide substrate material for cutting is manufactured, and the cutting edge portion is subjected to a honing process of R: 0.03 to form a chip shape of ISO standard / TNMG160408. Carbide substrates B-1 to B-6, and the carbide substrates B-1 ′ having a chip shape of ISO standard TEGX160304R by polishing the Al and Cu alloy carbide substrate materials. To B-6 ′.

Then, each of the above-mentioned superhard substrates A-1, 1 'to A-10, 10' and B-1, 1 'to B-6, 6' was ultrasonically cleaned in acetone and dried. 2, a plurality of cemented carbide substrates are mounted in a ring shape at a predetermined distance in the radial direction from the central axis of the rotary table in the vapor deposition apparatus shown in FIG. 2, and the cathode electrode of the magnetron sputtering apparatus on one side (Evaporation source), purity: 99.9 mass% Ti target, and cathode electrode (evaporation source) of the other side magnetron sputtering apparatus, purity: 99.6 mass% WC target across the rotary table Place and
(A) First, the inside of the apparatus is evacuated and kept at a vacuum of 0.01 Pa, and the inside of the apparatus is heated to 200 ° C. with a heater, and then Ar gas is introduced into the apparatus and Ar at a pressure of 0.5 Pa is introduced. In this state, a bias voltage of −800 V was applied to the carbide substrate rotating while rotating on the turntable in this state, and the surface of the carbide substrate was cleaned with Ar gas bombardment for 20 minutes.
(B) Next, both are applied to the electromagnetic coils of both magnetron sputtering devices arranged opposite to the vapor deposition device under the conditions of voltage: 50 V and current: 10 A, and the magnetic flux density in the mounting portion of the cemented carbide substrate is 140 G ( Gauss) and a heating temperature in the vapor deposition apparatus at 400 ° C., nitrogen and Ar are introduced as reaction gases at a rate of nitrogen flow rate: 300 sccm and Ar flow rate: 200 sccm. Introducing C ₂ H ₂ , nitrogen, and Ar as a reaction atmosphere composed of a mixed gas of nitrogen and Ar at a rate of C ₂ H ₂ flow rate: 50 sccm, nitrogen flow rate: 300 sccm, Ar flow rate: 230 sccm, a reaction atmosphere of a mixed gas of 1Pa of _C 2 decomposed gas of _{H 2} and nitrogen and Ar, the cathode electrode of the Ti target (evaporation ) Is applied with a sputtering power of 12 kW (frequency: 40 kHz), while glow discharge is generated on the cemented carbide substrate under the condition that a bias voltage of −100 V is applied. Forming a tight junction layer consisting of either or both of the TiN layer and TiCN layer having the target layer thickness shown in Tables 3 and 4,
(C) Furthermore, assuming that the conditions to be applied to the electromagnetic coil are predetermined values in the range of voltage: 50 to 100 V and current: 10 to 20 A, the magnetic flux density in the mounting portion of the cemented carbide substrate is 100 to 300 G (Gauss). ), The heating temperature in the vapor deposition apparatus is 400 ° C., the bias voltage of the carbide substrate is kept at −100 V, and the reaction gas in the vapor deposition apparatus is C ₂ H ₂ ( Hydrocarbon), nitrogen, and Ar are introduced at a predetermined flow rate within a range of C ₂ H ₂ flow rate: 25-100 sccm, nitrogen flow rate: 200-300 sccm, Ar flow rate: 150-250 sccm, and the reaction atmosphere is 1 Pa. A mixed gas of C ₂ H ₂ decomposition gas, nitrogen and Ar, and a cathode electrode (evaporation source) of the WC target of both the magnetron sputtering apparatuses, for example, output: Table 1 shows the same sputtering power in the range of 1 to 3 kW (frequency: 40 kHz) and the same Ti target with a predetermined sputtering power in the range of output: 3 to 8 kW (frequency: 40 kHz). 3 and 4, by forming a lubricious amorphous carbon-based film having a target composition and a target layer thickness by vapor deposition, the present invention surface-coated cemented carbide throwaway tip (hereinafter referred to as the present invention coated carbide tool) (Referred to as coated carbide chips of the present invention) 1,1 'to 16,16' were produced.

For comparison purposes, the surfaces of the superhard substrates A-1, 1 'to A-10, 10' and B-1, 1 'to B-6, 6' are ultrasonically cleaned in acetone. Then, in a dry state, the cathode electrode (evaporation source) shown in FIG. 3 is a Ti target sputtering device and the cathode electrode (evaporation source) is a WC target sputtering device facing each other on the rotary table of the evaporation device, A plurality of cemented carbide substrates are attached in a ring shape at a predetermined distance in the radial direction from the central axis of this,
(A) First, the inside of the apparatus is evacuated and kept at a vacuum of 0.01 Pa, and the inside of the apparatus is heated to 200 ° C. with a heater, and then Ar gas is introduced into the apparatus and Ar at a pressure of 0.5 Pa is introduced. In this state, a bias voltage of −800 V was applied to the carbide substrate rotating while rotating on the turntable in this state, and the surface of the carbide substrate was cleaned with Ar gas bombardment for 20 minutes.
(B) Next, in a state where the heating temperature in the vapor deposition apparatus is 300 ° C., nitrogen and Ar are introduced into the apparatus at a rate of nitrogen flow rate: 200 sccm, Ar flow rate: 300 sccm, and 1 Pa of nitrogen. A reaction atmosphere composed of a mixed gas of Ar and Ar, or C ₂ H ₂ , nitrogen, and Ar as reaction gases are introduced at a rate of C ₂ H ₂ flow rate: 40 sccm, nitrogen flow rate: 200 sccm, Ar flow rate: 300 sccm, and 1 Pa The reaction atmosphere is composed of a C ₂ H ₂ decomposition gas and a mixed gas of nitrogen and Ar, and a sputtering power of 12 kW (frequency: 40 kHz) is applied to the cathode electrode (evaporation source) of the Ti target, while the above carbide Tables 5 and 6 show the surface of the cemented carbide substrate by generating glow discharge under the condition that a bias voltage of −100 V is applied to the substrate. One of the target layer thickness TiN layer and TiCN layer, or an adhesion bonding layer consisting of both,
(C) Next, in a state where the heating temperature in the vapor deposition apparatus is 200 ° C., C ₂ H ₂ and Ar are flown at a predetermined flow rate within a range of C ₂ H ₂ flow rate: 40 to 80 sccm and Ar flow rate: 250 sccm. Introduced into a reaction atmosphere composed of 1 Pa of C ₂ H ₂ decomposition gas and Ar mixed gas, and the bias voltage applied to the cemented carbide substrate is set to −20 V to the cathode electrode (evaporation source) of the WC target. Is a condition of applying a predetermined sputtering power within a range of 4 to 6 kW (frequency: 40 kHz), and the lubricity of the target composition and target layer thickness shown in Tables 5 and 6 on the adhesive bonding layer. By forming an amorphous carbon-based film by vapor deposition, a comparative surface-coated cemented carbide throwaway tip (hereinafter referred to as a comparative coated carbide tip) 1,1'-16,16, corresponding to a conventional coated carbide tool It was prepared, respectively.

Next, the coated carbide tips 1, 1 'to 16, 16' of the present invention and the comparative coated carbide tips 1, 1 'to 16, 16' are screwed to the tip of the tool steel tool with a fixing jig. In the state
Work material: JIS / S10C round bar,
Cutting speed: 350 m / min. ,
Cutting depth: 1.2mm,
Feed: 0.18 mm / rev. ,
Cutting time: 5 minutes
Carbon steel dry high-speed cutting test under normal conditions (normal cutting speed is 120 m / min.),
Work material: JIS A5052 round bar,
Cutting speed: 1000 m / min. ,
Cutting depth: 1.4mm,
Feed: 0.3 mm / rev. ,
Cutting time: 20 minutes,
Dry high-speed cutting test of Al alloy under the conditions (normal cutting speed is 400 m / min.),
Work material: JIS C3710 round bar,
Cutting speed: 430 m / min. ,
Cutting depth: 1.2mm,
Feed: 0.25 mm / rev. ,
Cutting time: 20 minutes,
A dry high-speed cutting test of a Cu alloy under the conditions (normal cutting speed was 200 m / min.). In any cutting test, the flank wear width of the cutting edge was measured. The measurement results are shown in Tables 3-6.

As raw material powders, medium coarse WC powder having an average particle size of 4.5 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, 1.8 μm Cr ₃ C ₂ powder, 1.5 μm VC powder, 1.0 μm (Ti, W) C (mass ratio, TiC / WC = 50/50) powder, and 1 .8 μm Co powder was prepared, each of these raw material powders was blended in the blending composition shown in Table 7, added with wax, ball milled in acetone for 72 hours, dried under reduced pressure, and then pressed 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 types of round rod sintered bodies described above were subjected to grinding and shown in Table 7. In combination, a carbide substrate (end mill) having a diameter of 4 mm × 13 mm, a length of 6 mm × 13 mm, a size of 10 mm × 22 mm, and a size of 20 mm × 45 mm, and a four-blade square with a twist angle of 30 degrees. ) C-1 to C-8 were produced.

  Then, these carbide substrates (end mills) C-1 to C-8 were ultrasonically cleaned in acetone and dried, and charged in the vapor deposition apparatus shown in FIG. Under the same conditions, deposit one or both of the TiN layer and TiCN layer having the target layer thickness shown in Table 8, and the lubricating amorphous carbon-based film having the target composition and target layer thickness also shown in Table 8. By forming, end mills made of the present surface coated cemented carbide alloy (hereinafter referred to as the present coated carbide end mill) 1 to 8 as the coated carbide tools of the present invention were produced.

  Further, for the purpose of comparison, the above-mentioned carbide substrates (end mills) C-1 to C-8 were ultrasonically washed in acetone and dried, and charged in the vapor deposition apparatus shown in FIG. Under the same conditions as in Example 1, either or both of the TiN layer and TiCN layer having the target layer thickness shown in Table 9, and the lubricating composition amorphous having the target composition and target layer thickness also shown in Table 9 By subjecting the carbon-based coating to vapor deposition, comparative surface-coated cemented carbide end mills (hereinafter referred to as comparative coated carbide end mills) 1 to 8 corresponding to conventional coated cemented carbide tools were produced.

Next, of the present invention coated carbide end mills 1-8 and comparative coated carbide end mills 1-8, the present invention coated carbide end mills 1-3 and comparative coated carbide end mills 1-3 are as follows:
Work material: Plane dimension: 100 mm × 250 mm, thickness: 50 mm JIS / A5052 plate material,
Cutting speed: 300 m / min. ,
Axial cut: 4 mm
Radial notch: 0.7mm,
Table feed: 2200 mm / min,
With respect to the dry high-speed side cutting test of Al alloy under the following conditions (normal cutting speed is 180 m / min.), The coated carbide end mills 4 to 6 of the present invention and the conventional coated carbide end mills 4 to 6 are as follows:
Work material: Plane dimension: 100 mm × 250 mm, thickness: 50 mm JIS / C3710 plate material,
Cutting speed: 300 m / min. ,
Axial cut: 6mm,
Radial notch: 1.1mm,
Table feed: 2050 mm / min,
With respect to the dry high-speed side cutting test of Cu alloy under the conditions (normal cutting speed is 180 m / min.), The coated carbide end mills 7 and 8 of the present invention and the comparative coated carbide end mills 7 and 8 are as follows:
Work material: Plane dimension: 100 mm × 250 mm, thickness: 50 mm JIS / S10C plate,
Cutting speed: 350 m / min. ,
Axial cut: 8mm,
Radial notch: 2mm,
Table feed: 2050 mm / min,
Each of the dry high-speed side cutting tests (normal cutting speed is 200 m / min.) Of carbon steel under the above conditions is performed, and the flank wear width of the outer peripheral edge of the cutting edge is the service life of each side cutting test. The cutting length up to 0.1 mm, which is a standard, was measured. The measurement results are shown in Tables 8 and 9, 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 manufactured.

  Then, 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 above, either or both of the TiN layer and TiCN layer having the target layer thickness shown in Table 10, and the target composition and lubricating carbon having the target layer thickness also shown in Table 10 are used. The surface-coated cemented carbide drills (hereinafter referred to as the present invention coated carbide drills) 1 to 8 as the present invention coated carbide tools were produced respectively by vapor-depositing a film of an amorphous amorphous body. .

  For comparison purposes, the cutting edges of the above-mentioned carbide substrates (drills) D-1 to D-8 are honed, ultrasonically cleaned in acetone, and dried, as shown in FIG. In the vapor deposition apparatus, under the same conditions as in Example 1 above, either or both of the TiN layer and TiCN layer having the target layer thickness shown in Table 11, and the target composition and target layer also shown in Table 11 By producing a thick lubricious amorphous carbon-based film by vapor deposition, comparative surface coated carbide drills (hereinafter referred to as comparative coated carbide drills) 1 to 8 corresponding to conventional coated carbide tools are manufactured. did.

Next, of the present invention coated carbide drills 1-8 and comparative coated carbide drills 1-8, for the present invention coated carbide drills 1-3 and comparative coated carbide drills 1-3,
Work material: Plane dimension: 100 mm × 250 mm, thickness: 50 mm JIS / A5052 plate material,
Cutting speed: 280 m / min. ,
Feed: 0.4mm / rev,
Hole depth: 6mm,
With respect to the Al alloy wet high-speed drilling test (normal cutting speed is 120 m / min.), The present invention coated carbide drills 4-6 and comparative coated carbide drills 4-6,
Work material: Plane dimension: 100 mm × 250 mm, thickness: 50 mm JIS / S10C plate,
Cutting speed: 250 m / min. ,
Feed: 0.5mm / rev,
Hole depth: 12mm,
With regard to the wet high speed drilling test of carbon steel under the conditions of (normal cutting speed is 110 m / min.), The present invention coated carbide drills 7 and 8 and the comparative coated carbide drills 7 and 8,
Work material: Plane dimension: 100 mm × 250 mm, thickness: 50 mm JIS / C3710 plate material,
Cutting speed: 250 m / min. ,
Feed: 0.6mm / rev,
Hole depth: 20mm,
Wet Cu high-speed drilling cutting test under normal conditions (normal cutting speed is 110 m / min.), And any wet drilling cutting test (with water-soluble cutting oil) is used to relieve the cutting edge surface. The number of drilling processes until the surface wear width reached 0.3 mm was measured. The measurement results are shown in Tables 10 and 11, respectively.

  As a result, the coated carbide tips 1, 1 'to 16, 16' of the present invention as the coated carbide tool of the present invention, the coated carbide end mills 1 to 8 of the present invention, and the coated carbide drills 1 to 8 of the present invention, And the comparatively coated carbide tips 1, 1 'to 16, 16', the comparative coated carbide end mills 1 to 8 and the comparative coated carbide drills 1 to 8 corresponding to conventional coated carbide tools About the carbon-type film, when the composition was measured using an Auger spectroscopic analyzer and the layer thickness was measured using a scanning electron microscope, the target composition and the target layer thickness were both substantially the same as the target composition and the target layer thickness (5 cross sections). In addition, when the structure was observed using a transmission electron microscope, the coated carbide tool of the present invention had a crystalline Ti (C, N, ) Shows the structure in which compound compound fine particles are dispersed and distributed Meanwhile the conventional coating cemented carbide tools exhibited tissue of a single phase of the carbon-based amorphous substance.

From the results shown in Tables 3 to 11, the lubricating amorphous carbon-based film has a structure in which a crystalline Ti (C, N) -based compound fine particle is dispersed and distributed on a carbon-based amorphous body. Invented coated carbide tools show excellent wear resistance even when Al alloy, Cu alloy, and steel are machined under high-speed conditions. In a conventional coated carbide tool (comparative coated carbide tool) having a structure composed of a single phase of a carbon-based amorphous body, the wear of the lubricating amorphous carbon-based film under high-speed cutting conditions It is clear that the progress is very fast and that the service life is reached in a relatively short time.
As described above, the coated carbide tool of the present invention has excellent resistance not only to cutting under normal conditions, but also when cutting various kinds of work materials under high-speed cutting conditions. Since it exhibits wearability, it can be satisfactorily deal with labor saving and energy saving in cutting, and further cost reduction.

It is a schematic diagram which shows the result of having observed the structure | tissue of the lubricous amorphous carbon type | system | group film | membrane which comprises the coated carbide tool of this invention using the transmission electron microscope. The vapor deposition apparatus used for forming the adhesion joining layer and lubricous amorphous carbon-type film which comprise the coated carbide tool of this invention is shown, (a) is a schematic plan view, (b) is a schematic front view. is there. The vapor deposition apparatus used for forming the adhesion joining layer and lubricative amorphous carbon-type film which comprise the conventional coated carbide tool (comparative coated carbide tool) is shown, (a) is a schematic plan view, (b) Is a schematic front view.

Claims (1)

(A) on the surface of a cemented carbide substrate made of tungsten carbide based cemented carbide or titanium carbonitride cermet,
(B) In a magnetron sputtering apparatus, a Ti target is used as a cathode electrode (evaporation source), and a film is formed in a magnetic field in a reaction atmosphere composed of a mixed gas of nitrogen and Ar, or a mixed gas of hydrocarbon decomposition gas and nitrogen and Ar. Through a tight junction layer consisting of either or both of a titanium nitride layer and a titanium carbonitride layer and having an average layer thickness of 0.1 to 3 μm,
(C) In a magnetron sputtering apparatus, a tungsten carbide target and a Ti target are used as a cathode electrode (evaporation source), and a film is formed in a magnetic field in a reaction atmosphere composed of a hydrocarbon decomposition gas and a mixed gas of nitrogen and Ar. Measured with a spectroscopic analyzer,
W: 5 to 20 atomic%,
Ti: 5 to 20 atomic%,
Nitrogen: 0.5-18 atomic%,
And the balance is composed of carbon and inevitable impurities, and a structure in which fine particles of crystalline titanium carbonitride compound are dispersed and distributed on the base of the carbon-based amorphous body by observation with a transmission electron microscope. Made of a surface-coated cemented carbide alloy that exhibits excellent wear resistance and has a lubricious amorphous carbon-based coating formed by vapor-depositing a lubricating amorphous carbon-based coating having an average layer thickness of 1 to 13 μm. Cutting tools.

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