JPH07290302A - Coated tool member - Google Patents

Abstract

PURPOSE:To improve the peeling resistance and breakage resistance of a film by limiting the thickness of the aluminum oxide film near a ridge line and at the center section of a face, and unifying the film thickness. CONSTITUTION:Surfaces of a polyhedron base is coated with an aluminum oxide film to form a coated member. The thickness of the aluminum oxide film at a ridge line section up to 100mum toward the center section of a face from a ridge line is set to 0.5-6.5mum, and the thickness of the aluminum oxide film at the center section of the face is set to 0.5-5.0mum. The ratio of the thickness of the aluminum oxide film at the ridge line section against the thickness of the aluminum oxide film at the center section is set to 1.0-1.3. When this cutting tool is practically used, it has excellent peeling resistance of the film and excellent breakage resistance as a coated member, and the tool life is better by about two times or more than the conventional coated member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coated tool member formed by coating a surface of a base material with an aluminum oxide coating, and specifically, for example, a cutter, a cutting tool, a drill and a throw-away tool used as a cutting edge body thereof. The present invention relates to a cutting tool typified by a tip and an insert tip, and a coated tool member most suitable for a wear resistant tool typified by a slitter, a can making tool, and a die.

[0002]

2. Description of the Related Art Sintered alloys represented by cemented carbide and cermet or Al ₂ O ₃ based ceramics sintered bodies, ZrO ₂ based ceramics sintered bodies, Si ₃ N ₄ based ceramics sintered bodies,
A ceramic sintered body represented by a sialon-based ceramic sintered body is used as a base material, and a chemical vapor deposition (CV
A large number of coating members coated with an aluminum oxide coating by the D method) or the physical vapor deposition method (PVD method) have been proposed and put into practical use.

These coated members are intended to effectively utilize the excellent oxidation resistance, welding resistance and wear resistance of the aluminum oxide coating and the excellent strength and toughness of the base material. Japanese Patent Laid-Open No. 52-9481
No. 2, JP-A-52-94813, JP-A-52
-96911, Japanese Patent Laid-Open No. 52-100376, Japanese Patent Laid-Open No. 55-113874, Japanese Patent Laid-Open No. 55-1.
There are 48763, JP-A-57-32366 and JP-A-57-98670.

These conventional coated members are intended to effectively utilize the excellent oxidation resistance, welding resistance and wear resistance of a coating film, particularly an aluminum oxide coating film, and the excellent strength and toughness of a base material. However, when an aluminum oxide film is coated on a polyhedral base material typified by a throw-away tip of a cutting tool, the film thickness of the aluminum oxide coating near the ridgeline of the base material and in the center of the surface away from the ridgeline becomes In contrast, in the CVD method, in particular, the film thickness of the aluminum oxide film coated on the former is thicker than the latter,
As a result, there is a problem that the former easily peels off or is damaged in the vicinity of the ridgeline only by applying a small impact to the former.

[0005] As a representative example for solving this problem, there is JP-A-57-57865.

[0006]

Problems to be Solved by the Invention JP-A-57-5786
In Japanese Patent Publication No. 5 (1994), a cemented carbide or ceramic substrate is brought into contact with a gas containing at least one aluminum halide and a hydrolyzing agent and / or an oxidizing agent at a high temperature to form an aluminum oxide film on the surface of the substrate. In the coating method, there is described a method of adding sulfur, selenium and / or tellurium to the gas, wherein the concentration of sulfur, selenium and / or tellurium is 0.01 to 1% by volume based on the total gas volume. ing.

When the surface of the base material is coated with the aluminum oxide film by the method described in the above publication, the deposition rate of the aluminum oxide film is increased and a uniform and thin aluminum oxide film is coated. Compared to the film thickness at the center of the surface of the polyhedron, the film thickness in the immediate vicinity of the ridgeline is still thicker, and the ridgeline has a swelling, and when a large impact is applied or a sharp edge like a drill is applied. In the case of the polyhedron which has it, there is a problem that a defect is induced and the life becomes short.

The present invention solves the above-mentioned problems, and more specifically, is a covering member obtained by covering a surface of a base material having a polyhedron shape with a coating, and in the vicinity of a ridgeline of the polyhedron. It is an object of the present invention to provide a coated tool member in which the film thickness between the center portion of the surface and the surface is made uniform and the peeling resistance and fracture resistance of the coating are improved.

[0009]

The present inventors have found that when a polyhedron represented by a throw-away tip used as a cutting tool is coated with an aluminum oxide film, the film is easily peeled off, and the cause is a polyhedron. Based on the finding that the unevenness of the film thickness depending on the location, specifically, the film thickness in the vicinity of the ridgeline becomes thicker than the film thickness in the central portion of the surface, the countermeasures were considered. However, in the vicinity of the ridge, the reaction gas directly reacts at the interface of the base material,
Since the reaction gas and the base material interface are accompanied by a diffusion reaction in the central part, the formation rate of the aluminum oxide film is different between the two.Therefore, hydrogen sulfide and carbon dioxide are contained in the reaction gas to contain hydrogen sulfide. By increasing the amount and adjusting both gas ratios, coating treatment time and coating treatment temperature, and limiting the overall coating thickness, we found that the coating thickness near the ridgeline and in the central portion can be made uniform. Thus, the present invention has been completed.

That is, the coated tool member of the present invention is a coated member obtained by coating the surface of a polyhedral base material having a ridge and a surface with an aluminum oxide coating, up to 100 μm from the ridge toward the center of the surface. The thickness of the aluminum oxide coating on the ridge line is 0.5 to 6.5 μm, and the thickness of the aluminum oxide coating on the central portion is 0.5 to 6.5 μm.
The thickness of the aluminum oxide film is 5.0 μm, and the ratio of the thickness of the aluminum oxide film at the ridge to the thickness of the aluminum oxide film at the center is 1.0 to 1.3.

The base material of the coated tool member of the present invention is, for example, a cemented carbide, a sintered alloy represented by cermet, various ceramics sintered bodies, high speed steel, die steel, stainless steel. Made of various types of steel,
Among these, it is preferable to use a sintered alloy or a ceramics sintered body, because the effect is highly exhibited.
Regarding the shape of the base material, all shapes typified by throw-away inserts that have been conventionally used as cutting tools are targeted, and specifically, a cylindrical plate body or a conical plate body with a conical tip cut off. 5 typified by a trihedral, a triangular prism plate, or a truncated triangular pyramid plate
It is composed of a polyhedron such as a tetrahedron and other hexahedrons and heptahedrons.

[0012] Of the ridges and the planes that make up this base material, the ridges that represent the vicinity of the ridges may be chamfered if the ridges are chamfered. If the ridgeline is R-honed, use the imaginary line that is a vertical line from the intersection point that is formed by extending both sides to the R-honing, or use the center of the R-honing arc as the reference point. Good. On the other hand, the center portion of the surface is a portion excluding the ridge portion, and may be a location of approximately ½ between the ridge lines.

When the thickness of the aluminum oxide coating on the ridge and the thickness of the aluminum oxide coating on the central portion are each less than 0.5 μm, the effects of the wear resistance and the welding resistance by the aluminum oxide coating are weakened. When the thickness is more than 6.5 μm and when the latter is more than 5.0 μm, the coating is easily peeled off. Further, when the ratio of the thickness of the aluminum oxide coating at the ridge to the thickness of the aluminum oxide coating at the central portion is less than 1.0, it is difficult to select the coating condition, and conversely 1 If it exceeds 0.3, the peeling resistance and the chipping resistance are lowered and the life is shortened.

Depending on the material of the base material, an intermediate layer made of a metal, an alloy or a metal compound may be interposed between the base material and the aluminum oxide coating to act as an intermediary for the adhesion between the base material and the aluminum oxide coating. In particular, it is preferable that the intermediate layer has Ti carbide, nitride, carbon oxide, oxynitride, carbonitride, oxycarbonitride, or complex carbide containing Ti and Al, complex nitride, complex carbonate. It is preferable that at least one kind of composite nitrogen oxide, composite carbonitride, and composite carbonitride is composed of a single layer or multiple layers. When the thickness of this intermediate layer is less than 0.5 μm, the mediating action of the adhesiveness between the base material and the aluminum oxide coating becomes weak,
If the effect of enhancing the wear resistance of the intermediate layer is reduced, on the contrary, if the thickness exceeds 8 μm, the adverse effect caused by the non-uniformity of the thickness of the aluminum oxide film, specifically, peeling resistance and chipping resistance are also reduced. Therefore, the thickness is determined to be 0.5 to 8 μm, and the thickness is particularly preferably 1 to 7 μm.

When the intermediate layer is interposed, the total coating thickness of the intermediate layer and the aluminum oxide coating in the central portion is 1 to 15 μm, and the total coating thickness of the intermediate layer and the aluminum oxide coating in the central portion. It is preferable that the ratio of the total film thickness of the intermediate layer and the aluminum oxide coating in the ridge portion is 1.0 to 1.2 in order to improve the peeling resistance and the chipping resistance.

The coated tool member of the present invention comprises a conventional substrate, a conventional CVD method, a PVD method, or a combination thereof, which is used to coat the surface of the substrate with a lapping treatment. Although it can also be produced by, but not an industrial method, the production of the aluminum oxide film, in an atmosphere containing hydrogen sulfide gas and carbon dioxide gas,
It is preferable to carry out the CVD method in which the treatment is performed by controlling the gas ratio of both, the coating treatment temperature, and the coating treatment time.

[0017]

According to the coated tool member of the present invention, the aluminum oxide film thicknesses at the ridge and the central portion and the ratio of the aluminum oxide film thickness at the ridge portion to the aluminum oxide film thickness at the central portion are particularly advantageous. It has a function of preventing the peeling resistance of the aluminum oxide film in the portion.

[0018]

[Example 1] 90% WC-10% (wt%) composition component
SNMG12 is a cemented carbide with a JIS cutting tool standard shape
The surface of the base material was coated with the intermediate layer shown in Table 2 by the conventional CVD method using the polyhedral base material of 0408. (The layer adjacent to the substrate surface is the first layer,
First layer to fourth layer are sequentially coated) Then, the surface of the intermediate layer is coated with an aluminum oxide film at the temperature, pressure and gas composition ratios shown in Table 1, and the invention products 1 to 6 and the comparative product 1 are coated. ~ 6 was obtained.

The products 1 to 6 of the present invention thus obtained and the comparative products 1 to 1
The coating composition and coating thickness of No. 6 were examined using a scanning electron microscope, a metallurgical microscope, and an X-ray diffractometer, and the results are also shown in Table 2. The ratio of the thickness of the ridge line portion to the thickness of the central portion obtained from the thicknesses of all the intermediate layers and the thickness of the aluminum oxide coating shown in Table 2 was obtained and shown in Table 3.

Next, using the products 1 to 3 of the present invention and the comparative products 1 to 3, a work material: S45C (H _B 190), a cutting speed: 1
80m / min, depth of cut: 3mm, feed: 0.3mm /
Rev, cutting time: A dry cutting test was performed under the conditions of 60 min, and the average flank wear amount and rake face wear depth at that time were obtained and are also shown in Table 3. The products of the present invention 4 to 6
And the comparative products 4 to 6 are used for the work material SNCM439 (H _B
350), cutting speed: 100 m / min, depth of cut: 2 m
m, feed: 0.3 mm / rev, cutting time: 40 min
The dry cutting test was carried out under the conditions described in 1 above, and the average flank wear amount and rake face wear depth at that time were obtained and are also shown in Table 3.

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

[Table 3]

[0024]

Example 2 A composition component is 58% Ti (CN) -10% W.
C-10% TaC-2% NbC-10% Co-10% N
i (wt%) cermet sintered alloy, using a base material whose shape is SNMG120408 of JIS cutting tool standard,
In the same manner as in Example 1, the surface of the substrate was coated with the intermediate layer and the aluminum oxide film to obtain the products 7 to 9 of the present invention and the comparative products 7 to 9. Table 4 shows the coating conditions of the aluminum oxide coating at this time.
Table 5 shows the composition and film thickness of the intermediate layer, and the crystal structure and film thickness of the aluminum oxide film, which were examined in the same manner as in Example 1.

Inventive products 7 to 9 and comparative products 7 to 9 thus obtained
Work material: SCM440 (H _B 220), cutting speed: 150 m / min, depth of cut: 1 mm, feed:
A dry cutting test was performed under the conditions of 0.2 mm / rev and cutting time: 40 min, and the average flank wear amount and rake face wear depth at that time were obtained and are shown in Table 6 together.

[0026]

[Table 4]

[0027]

[Table 5]

[0028]

[Table 6]

[0029]

Example 3 A composition component is 96% Si ₃ N ₄ -2% Al ₂ O ₃
In _{-2% Y 2 O 3 (wt} %) ceramic sintered body, with a substrate shape is in SNMG120408 of JIS cutting tool standards, intermediate layer and aluminum oxide coating on the surface of the substrate in the same manner as in Example 1 Were coated to obtain inventive products 10 to 12 and comparative products 10 to 12. Table 7 shows the coating conditions of the aluminum oxide film at this time, and Table 8 shows the composition and film thickness of the intermediate layer and the crystal structure and film thickness of the aluminum oxide film examined in the same manner as in Example 1.

Using the products 10-12 of the present invention and the comparative products 10-12 thus obtained, the work material: FC350 (H _B 20
0), cutting speed: 200 m / min, depth of cut: 1.5 m
m, feed: 0.3 mm / rev, cutting time: 40 min
The dry cutting test was performed under the conditions of No. 1 and the average flank wear amount and rake face wear depth at that time were obtained and shown in Table 9.

[0031]

[Table 7]

[0032]

[Table 8]

[0033]

[Table 9]

[0034]

INDUSTRIAL APPLICABILITY The coated tool member of the present invention is superior in peeling resistance of the coating when it is practically used as a cutting tool and has a fracture resistance as a coated member, as compared with a comparative product which is a conventional coated member. There is an effect that the tool life is excellent and, as a result, the tool life is more than doubled.

Claims (5)

[Claims] 1. A covering member obtained by coating an aluminum oxide film on the surface of a polyhedral substrate having a ridge and a surface, wherein the aluminum oxide film is present on the ridge from the ridge toward the center of the surface to 100 μm. Thickness is 0.5 ~
6.5 μm, the thickness of the aluminum oxide coating at the central portion is 0.5 to 5.0 μm, and the ratio of the thickness of the aluminum oxide coating at the ridge portion to the thickness of the aluminum oxide coating at the central portion. Is 1.0 to 1.3
A coated tool member comprising: 2. A covering member comprising a polyhedron base material having a ridge and a surface, the surface of which is coated with an aluminum oxide film, wherein a Ti carbide, a nitride or a carbonic acid is provided between the base material and the aluminum oxide film. Compounds, nitride oxides, carbonitrides, carbonitride oxides, or compound carbides containing Ti and Al, compound nitrides, compound carbonates, compound nitrogen oxides, compound carbonitrides, compound carbonitrides Is coated with at least one kind of intermediate layer consisting of a single layer or multiple layers, and the thickness of the intermediate layer is 0.5.
.About.8 .mu.m, from the ridgeline toward the center of the surface 10
The thickness of the aluminum oxide coating on the ridge line portion up to 0 μm is 0.5 to 6.5 μm, and the thickness of the aluminum oxide coating on the central portion is 0.5 to 5.0 μm,
A coated tool member, wherein the ratio of the thickness of the aluminum oxide coating on the ridge portion to the thickness of the aluminum oxide coating on the central portion is 1.0 to 1.3. 3. The total film thickness of the intermediate layer and the aluminum oxide coating film in the central portion is 1 to 15 μm.
And the ratio of the total film thickness of the intermediate layer and the aluminum oxide film in the central portion to the total film thickness of the intermediate layer and the aluminum oxide film in the ridge portion is 1.0 to 1. 2. The method according to claim 2, wherein
The coated tool member described. 4. The coated tool member according to claim 1, wherein the base material is made of cemented carbide or cermet. 5. The coated tool member according to claim 1, 2, 3 or 4, wherein the coated tool member is used for a cutting tool.