JPH10130843A - Cutting tool made of surface coated cement, excellent in chipping resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting tool made of surface coated cermet, showing superior cattability over a long period and excellent in chipping resistance. SOLUTION: The cutting tool made of surface coated cermet is obtained by forming, by means of chemical vapor deposition and/or physical vapor deposition, a hard coating layer, constituted of one or >=2 kinds among Ti compound layers consisting of TiC layer, TiN layer, TiCN layer, TiO2 layer, TiCO layer, TiNO layer, and TiCNO layer and an Al2 O3 layer, onto the surface of a base material composed of WC-base cemented carbide or TiCN-base cement to 3-20μm average layer thickness. In this case, an Al-O type amorphous layer, prepared by incorporating, by weight, 1-15% Ti, 0.005-0.1% Cl, and 0.001-0.1% N into the Al2 O3 constituting the Al2 O3 layer and forming the structure into amorphous structure, is interposed in a manner to be adjacent to the surface and/or the rear side surface of the Al2 O3 layer to 0.2-10μm average layer thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention, aluminum oxide which constitutes the hard coating layer (hereinafter, Al ₂ O indicated by ₃₎ relates to an improvement of the layer, which is no decrease in toughness even thickened, and excellent It has interlayer adhesion, so it can be used not only for continuous cutting of steel or cast iron, for example, but also for intermittent cutting. The present invention relates to a surface-coated cermet cutting tool exhibiting performance (hereinafter referred to as a coated cermet tool).

[0002]

2. Description of the Related Art Conventionally, a layer of Ti carbide (hereinafter referred to as TiC) is formed on the surface of a tungsten carbide-based cemented carbide substrate or a titanium carbonitride-based cermet substrate (hereinafter, these are collectively referred to as a cermet substrate). , Nitride (hereinafter also referred to as TiN) layer, carbonitride (hereinafter referred to as TiCN) layer, oxide (hereinafter referred to as TiO ₂ ) layer, carbonate (hereinafter referred to as TiCO) layer, oxynitridation Object (hereinafter, TiN
O) and one or more Ti compound layers consisting of a carbonitride oxide (hereinafter referred to as TiCNO) layer and an Al ₂ O ₃ layer. ~
Coated cermet tools are known which are chemically and / or physically deposited with an average layer thickness of 20 μm. Further, in particular, the Al constituting the hard coating layer of the coated cermet tool described above.
_{The 2} O ₃ layer serves as a reaction gas in aluminum trichloride (hereinafter referred to as AlCl ₃ ) by volume%:
20%, carbon dioxide (hereinafter referred to as CO ₂ ): 0.5 to 30%, [If necessary, carbon monoxide (CO) or hydrogen chloride (H
Cl): 1 to 30%], hydrogen: residual, and a hydrogen-based reaction gas having a composition of: reaction temperature: 950 to 1100 ° C .; atmospheric pressure: 20 to 200 torr. ing.

[0003]

On the other hand, in recent years, the use of FA in cutting has been remarkable, and there has been a strong demand for labor saving. With this, a further extension of the service life of coated cermet tools has been required. As a corresponding measure,
Of the hard coating layer of the same, and more particularly excellent in oxidation resistance and thermal stability have been further thickening widely studied of the Al ₂ O ₃ layer having a high hardness, the the Al ₂ O ₃ layer Is
When this is thickened, a decrease in toughness is unavoidable, and in addition to insufficient interlayer adhesion with other Ti compound layers constituting the hard coating layer, when this is used for interrupted cutting of steel or cast iron, for example. At present, chipping is liable to occur on the cutting blade, which causes the service life to be shortened in a relatively short time at present.

[0004]

Means for Solving the Problems Accordingly, the present inventors have
From the above viewpoint, attention is paid to the Al ₂ O ₃ layer constituting the hard coating layer of the coated cermet tool, and the toughness is reduced when the thickness is increased, and the interlayer adhesion to the Ti compound layer as another constituent layer is reduced. as a result of research in order to improve, by chemical vapor deposition and / or physical vapor deposition, as a reaction gas, in place of the above conventional hydrogen-based reactive gas, in volume%, basically, AlCl _3: 1 10% hydrogen (hereinafter, indicated by H _2): 1 to 5%, of nitrogen oxides (hereinafter, indicated by NO): 16 to 30%, titanium tetrachloride (hereinafter, indicated by TiCl _4): 0.05 ~
An inert gas-based reaction gas having a composition of 0.7%, inert gas: remaining, and the following reaction conditions and atmosphere pressures were used: reaction temperature: 700 to 900 ° C., atmosphere pressure: 20 to 200 torr, performed at conditions layering, the formed layer is, Al ₂ O ₃ constituting the the Al ₂ O ₃ layer of conventional hard coating layer Ti, C
l, and N, that is, the main component is Al and oxygen (O), and has a composition containing Ti, Cl, and N, and the Ti, Cl, and N
By adjusting the content ratio of T mainly by adjusting the composition of the inert gas-based reaction gas and the reaction atmosphere, T
When i: 1 to 15%, Cl: 0.005 to 0.1%, and N: 0.001 to 0.1%, the resulting Al—O containing Ti, Cl, and N is obtained. The system layer is
The above Al constituting the hard coating layer by the coexistence of these components
_{As well as the 2} O ₃ layer, it also adheres well to the Ti compound layer and has an amorphous structure, so that it is formed adjacent to the upper surface and / or lower surface of the Al ₂ O ₃ layer of the conventional hard coating layer. When interposed, the Al—O-based amorphous layer and the Al ₂
Even if the film is thickened in a state where the O ₃ layer is laminated, the decrease in toughness is significantly suppressed, and therefore, the Al 3
Wherein the -O-based amorphous layer the Al ₂ O ₃ layer, further wherein the Ti compound layer and the coated cermet tool of the hard coating layer formed becomes formed on the cermet substrate surface, the Al-O-based amorphous Since the layer has the same properties as the Al ₂ O ₃ layer, it has excellent oxidation resistance, thermal stability, and high hardness, so it can be used not only for continuous cutting of steel and cast iron, but also for intermittent Research results show that even when used for cutting, the cutting edge does not generate chipping or the like and exhibits excellent cutting performance over a long period of time.

The present invention has been made based on the above research results.
The surface of the cermet substrate, TiC
Layer, TiN layer, TiCN layer, TiO_Two Layer, TiCO layer,
Ti compound layer including TiNO layer and TiCNO layer
One or more of the above, and Al_TwoO_ThreeConsists of layers and
Hard coating layer with an average layer thickness of 3 to 20 μm
A coated cermet tool comprising:_Two O_Three Layers
Constituting Al_Two O_Three % By weight, Ti: 1 to 15%, Cl: 0.005 to 0.1%, N: 0.001 to 0.1%. O
The amorphous amorphous layer _Two O_Three The upper surface of the layer and / or
Adjacent to the lower surface with an average layer thickness of 0.2 to 10 μm
Al_Two O_Three Layer and an Al-O based amorphous layer
Thickness to suppress toughness reduction and improve interlayer adhesion
Scales up, thereby improving chipping resistance of the cutting edge
It is characterized by a coated cermet tool
You.

[0006] The Ti, C in the Al-O-based amorphous layer constituting the hard coating layer of the coated cermet tool of the present invention.
l and N are, as described above, A
It improves the interlayer adhesion to the l ₂ O ₃ layer and the Ti compound layer. Therefore, even when the content of Ti is less than 1%, the content of Cl and N is less than 0.005%. And less than 0.001%, the desired effect cannot be obtained in the above-mentioned action, while the content of any one of these components is Ti: 15%, Cl: 0.1%,
If N exceeds 0.1%, the properties of an Al—O-based amorphous layer having properties equivalent to those of the Al ₂ O ₃ layer will be impaired. The amounts are respectively: Ti: 1 to 15%, Cl: 0.005 to
0.1%, N: 0.001 to 0.1%. Also,
The average layer thickness of the Al—O-based amorphous layer is set to 0.2 to 10 μm. If the layer thickness is less than 0.2 μm, the desired effects cannot be obtained in improving the interlayer adhesion and the toughness. On the other hand, if the thickness exceeds 10 μm, chipping is likely to occur on the cutting edge. Further, the reason why the average layer thickness of the hard coating layer is set to 3 to 20 μm is that if the layer thickness is 3 μm, it is not possible to secure the desired excellent wear resistance. This is because the chipping property is reduced.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the coating cermet of the present invention will be described.
The tool will be specifically described with reference to an example. As raw material powder
WC powder having an average particle size of 2.8 μm;
4.9 μm coarse WC powder, 1.5 μm (Ti_0.3 
W_0.7 ) C powder, 1.2 μm (Ti_0. FourW_0.6 ) C
N powder, 1.2 μm (Ta_0.9Nb_0.1) C powder,
1.3 μm (Ti_0.6W_0.3Mo_0.1) CN powder,
1.5μm TiCN powder, 1.5μm TaC powder
Powder, 1.5 μm NbC powder, 1.5 μm Mo _Two
C powder, 2.0 μm Ni powder, and 1.1 μm
Are prepared, and these raw material powders are shown in Table 1.
Formulated into the composition, wet-mixed for 72 hours in a ball mill,
After drying, use ISO / CNMG120408 (carbide substrate
A to D and cermet substrates F and G) and SEE
N2AFTN1 (for carbide substrate E)
Press molded into a body, and this green compact is also shown in Table 1.
Carbide substrates A to E and S
-Met substrates F and G were produced. In addition,
100 torr CH against carbide substrate B_Four Gas atmosphere
Air, temperature: Hold at 1400 ° C for 1 hour, then slowly cool carburizing
After the treatment, the carbon adhering to the surface of the carbide substrate
The surface is removed by removing Co by acid and barrel polishing.
Maximum Co content at a position of 11 μm from the surface: 15.9 weight
%, Depth: forming a Co-enriched zone of 42 μm on the substrate surface
did. The super-hard substrates A and D are not sintered.
Up to 17 μm from the surface
Amount: 9.1% by weight, depth: 23 μm Co-enriched band
And the remaining cemented carbide substrates C and E have the C
o No enriched zone is formed and the overall structure is homogeneous
It was. Table 1 shows that the above-mentioned carbide substrates A to E and
And the internal hardness of the cermet bases F and G (Rockwell hardness)
A scale).

Then, the surface of each of the superhard substrates A to E and the cermet substrates F and G is honed, and a conventional chemical vapor deposition apparatus is used.
CN has a vertically elongated crystal structure described in JP-A-6-8010, and p-TiCN has a normal granular crystal structure) and under the conditions shown in Table 3, The coated cermet tools 1 to 19 of the present invention and the conventional coated cermet tools 1 to 12 were formed by forming a hard coating layer having the composition and the target layer thickness (layer thickness at the flank of the cutting edge) shown in Tables 4 and 5, respectively. Manufactured. The identification of the Al—O-based amorphous layer, the Al ₂ O ₃ layer, and the Ti compound layer that constitute the hard coating layers of the various coated cermet tools obtained as described above was based on the escape of the cutting edge in each coated cermet tool. This was performed by observing the X-ray diffraction pattern on the surface.

Further, in order to evaluate the chipping resistance of the cutting blade, the coated cermet tools 1 to 8 of the present invention are used.
For the conventional coated cermet tools 1 to 4, the work material was a JIS SCM440 round bar, and the cutting speed was 350 m / min. , Depth of cut: 1.5 mm, feed: 0.3 mm / rev. Cutting time: 10 minutes, dry continuous cutting test of alloy steel under the following conditions: Work material: JIS SCM440, 4 longitudinally spaced round bars at regular intervals in the longitudinal direction, Cutting speed: 120 m / min. Infeed: 1.5 mm. Feed: 0.3 mm / rev. , Cutting time: 10 minutes, dry intermittent cutting test of the alloy steel was performed under the following conditions, and the flank wear width of the cutting edge was measured in each cutting test.

[0010] The coated cermet tool 9 of the present invention.
Work material: JIS SCr420 round bar, Cutting speed: 300 m / min. Infeed: 1.5 mm. Feed: 0.3 mm / rev. , Cutting time: 10 minutes, Dry continuous cutting test of alloy steel under the following conditions: Work material: JIS SCr420, four longitudinally spaced round bars at regular intervals in the longitudinal direction, Cutting speed: 150 m / min. Infeed: 1.5 mm. Feed: 0.3 mm / rev. , Cutting time: 10 minutes, dry intermittent cutting test of the alloy steel was performed under the following conditions, and the flank wear width of the cutting edge was measured in each cutting test.

The present invention also provides a coated cermet tool 12-1.
4 and the conventional coated cermet tools 7 to 9 were: Work material: JIS FC200 round bar, Cutting speed: 300 m / min. Infeed: 1.5 mm. Feed: 0.3 mm / rev. , Cutting time: 25 minutes, Dry continuous cutting test of cast iron under the following conditions: Work material: JIS FC200, 4 longitudinally-spaced round bars at regular intervals in the longitudinal direction, Cutting speed: 150 m / min. Infeed: 1.5 mm. Feed: 0.3 mm / rev. , Cutting time: 20 minutes, a dry intermittent cutting test of cast iron was performed under the following conditions, and the flank wear width of the cutting edge was measured in each cutting test.

Further, the present invention also provides a coated cermet tool 1.
5 to 17 and the conventional coated cermet tool 10, a work material: a square member of JIS / SNCM439 having a size of 100 mm in width × 500 mm in length; p. m. Cutting speed: 200 m / min. , Depth of cut: 2 mm. , Feed: 0.2mm / tooth, Cutting time: 4 passes (cutting time of 1 pass: 5.3 minutes), Dry milling (intermittent cutting) test of alloy steel under the following conditions: flank wear of cutting edge The width was measured.

Similarly, the coated cermet tools 18, 1
9 and the conventional coated cermet tools 11 and 12, the work material was a JIS S25C round bar, and the cutting speed was 350 m / min. Infeed: 1 mm. Feed: 0.25 mm / rev. , Cutting time: 20 minutes, dry continuous cutting test of carbon steel under the following conditions: Work material: JIS S25C, 4 longitudinally spaced round bars at regular intervals in the longitudinal direction, Cutting speed: 200 m / min. Infeed: 1 mm. Feed: 0.25 mm / rev. A dry intermittent cutting test of carbon steel was performed under the following conditions: cutting time: 20 minutes, and the flank wear width of the cutting edge was measured in each cutting test.

[0014]

[Table 1]

[0015]

[Table 2]

[0016]

[Table 3]

[0017]

[Table 4]

[0018]

[Table 5]

[0019]

[Table 6]

[0020]

From the results shown in Tables 4 to 6, it can be seen from the results shown in Tables 4 to 6 that as the hard coating layer, an Al—O-based amorphous layer containing Ti, Cl, and N was formed using an inert gas-based reaction gas. The present invention coated cermet tools 1 to 19, in which a thicker film is formed by interposing a film adjacent to the upper surface and / or lower surface of an Al ₂ O ₃ layer formed using a hydrogen-based reaction gas,
Since the l-O-based amorphous layer contributes to the improvement of toughness and interlayer adhesion, the hard-coated layer has a higher hardness than the conventional coated cermet tools 1 to 12 in which the Al-O-based amorphous layer is not present. Thus, it is clear that continuous cutting of steel and cast iron shows excellent wear resistance, and in particular, intermittent cutting shows even more excellent chipping resistance. As mentioned above, coated cermet tool of the present invention, the Al-O-based amorphous layer constituting this hard coating layer, the thicker a laminate with the Al ₂ O ₃ layer, which in a decrease in toughness Remarkably suppressed, and said Al
_Since it has a good adhesion to the ₂ O ₃ layer and the Ti compound layer, it shows excellent chipping resistance, especially in intermittent cutting as well as continuous cutting of steel or cast iron, for example, and is excellent over a long period of time. Since the cutting performance is enhanced, it is possible to satisfactorily cope with FA and labor saving in cutting.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor ▲ Isao Toshi 1511 Furimagi, Ishishita-cho, Yuki-gun, Ibaraki Prefecture Inside the Tsukuba Works, Mitsubishi Materials Corporation (72) Inventor Yuki Hamaguchi, Ijimo-machi, Ishishita-cho, Ibaraki Prefecture 1511 Thu Inside Mitsubishi Materials Corporation Tsukuba Factory

Claims (1)

[Claims] Claims 1. A tungsten carbide-based cemented carbide substrate or a titanium carbonitride-based cermet substrate, a Ti carbide layer, a nitride layer, a carbonitride layer, an oxide layer, a carbon oxide layer, a nitrogen oxide layer, And / or physical vapor deposition of a hard coating layer composed of one or more of Ti compound layers composed of a carbonitride oxide layer and an aluminum oxide layer with an average layer thickness of 3 to 20 μm. In the surface-coated cermet cutting tool, the aluminum oxide constituting the aluminum oxide layer is added to the aluminum oxide in a weight percentage of Ti: 1 to 15%, Cl: 0.005 to 0.1%, N: 0.001 to 0%. 0.1%, and an Al-O having an amorphous structure.
A system amorphous layer on the upper surface of the aluminum oxide layer and / or
Alternatively, a cutting tool made of a surface-coated cermet having excellent chipping resistance, wherein the cutting tool is provided with an average layer thickness of 0.2 to 10 μm adjacent to the lower surface.