JPH0938806A - Cutting tool made of surface coating carbonitriding titanium group cermet having excellent close adhesiveness of hard coating layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting tool made of surface coating TiCN group cermet wherein a hard coating layer has the excellent close adhesiveness. SOLUTION: A cutting tool made of surface coating TiCN group cermet is composed of a substance; wherein a hard coating layer composed of two-kind or more plural layers out of TiC, TiN, TiCN, TiCO, TiCNO, and Al2 O3 ; is formed; at a mean layer thickness of 0.5-20μm, on the surface of a TiCN group cermet base substance via a chemical vapor-deposition closely adhesive joining layer, having a mean layer thickness of 0.1-5μm and a composition containing Ni; 4-25%, and Co; 15-50% in wt.%, and wherein the remainder is actually composed of TiC or TiCN.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a surface which has excellent adhesion and adhesion of a hard coating layer to a substrate surface, and therefore does not cause peeling of the hard coating layer even at high speed cutting and exhibits excellent wear resistance for a long period of time. The present invention relates to a coated titanium carbonitride-based cermet cutting tool (hereinafter referred to as a coated cermet cutting tool).

[0002]

2. Description of the Related Art Conventionally, generally, for example, JP-A-54-11.
As described in Japanese Patent No. 7510, on the surface of a titanium carbonitride-based cermet substrate (hereinafter referred to as cermet substrate),
By chemical vapor deposition and / or physical vapor deposition, Ti carbide, nitride, carbonitride, carbon oxide, and carbonitride oxide,
And aluminum oxide (hereinafter, TiC and Ti, respectively)
N, TiCN, TiCO, TiCNO, and Al ₂ O
₃ )), a coated cermet cutting tool formed by forming a hard coating layer composed of two or more multi-layers with an average layer thickness of 0.5 to 20 μm is known, and this is, for example, steel or cast iron. It is also known to be used for continuous cutting and interrupted cutting.

[0003]

On the other hand, in recent years, cutting machines have been remarkably improved in performance, and there is also a strong demand for labor saving in cutting, and along with this, there is a demand for cutting to be even faster. However, when performing high-speed cutting using the above conventional coated cermet cutting tool, because the adhesion bondability of the hard coating layer to the cermet substrate is not sufficient, peeling easily occurs in the hard coating layer, a relatively short time The current situation is that it reaches the end of its useful life.

[0004]

Means for Solving the Problems Accordingly, the present inventors have
From the above viewpoint, focusing on the above-mentioned conventional coated cermet cutting tool, as a result of conducting research to improve the adhesion bondability of the hard coating layer to the cermet substrate, the surface of the cermet substrate was chemically vapor deposited. Using the method, wt%
And contains Ni: 4 to 25%, Co: 15 to 20%,
When the ordinary hard coating layer described above is formed on the bonding layer having the composition of the balance substantially consisting of TiC or TiCN, the chemical vapor deposition bonding layer is formed on both the cermet substrate and the hard coating layer. Since the coated cermet cutting tool as a result of this has excellent adhesion bondability even with respect to the above, the research result that the hard coating layer does not peel even at high speed cutting and exhibits excellent wear resistance for a long period of time. Is obtained.

The present invention has been made based on the above-mentioned research results, and Ti is formed on the surface of a cermet substrate.
C, TiN, TiCN, TiCO, and TiCNO,
And 0.5 to 2 multi-layers of two or more of Al ₂ O ₃
In a coated cermet cutting tool formed with an average layer thickness of 0 μm, the weight ratio between the cermet base and the hard coating layer is Ni: 4 to 25%, Co: 15
˜50%, the balance being essentially TiC or Ti
The chemical vapor deposition adhesion bonding layer having a composition of CN is 0.1
This is characterized by a coated cermet cutting tool having an excellent tight bondability with a hard coating layer, which is interposed with an average layer thickness of ˜5 μm.

The chemical vapor deposition adhesion bonding phase constituting the coated cermet cutting tool of the present invention is, for example, TiCl ₄ : 0.
_{5~10%, CH 4: 0.5~10%} , CoCl 2:
0.1 to 5%, NiCl ₂ : 0.1 to 5%, H ₂ : a composition consisting of the rest, TiCl ₄ : 0.5 to 10%,
_{CH 4: 0.5~10%, N 2} : 1~50%, CoCl
₂ : 0.1 to 5%, NiCl ₂ : 0.1 to 5%, H ₂ :
It can be formed under normal conditions, except that the composition of the rest (volume% or more) is used. With regard to its composition, the coexistence of Ni and Co exhibits excellent adhesive bondability to both the cermet substrate and the hard coating layer. Therefore, in any of Ni and Co, the content is Ni. : Less than 4% and Co: 15
%, It is not possible to secure the desired excellent adhesive bondability, while Ni: 25
% And Co: 50%, the heat resistance rapidly decreases, which causes peeling of the hard coating layer. Therefore, the content of Ni is 4 to 25%, preferably 5 to 5%. 15%, Co: 15 to 50%, preferably 15 to 35%. Further, as for the average layer thickness, if the average layer thickness is less than 0.1 μm, desired excellent adhesive bondability cannot be secured, while if the average layer thickness exceeds 5 μm, the hard coating layer peels off. Therefore, the average layer thickness is 0.1 to 5 μm, preferably 0.5.
˜2 μm. Further, the average layer thickness of the hard coating layer is 0.
When the average layer thickness is less than 0.5 μm, the desired effect of improving wear resistance cannot be obtained, while when the average layer thickness exceeds 20 μm, the hard coating layer is chipped or chipped (finely chipped). ) Is more likely to occur, and an average layer thickness of 3 to 13 μm is desirable.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the coated cermet cutting tool of the present invention will be specifically described with reference to Examples. As raw material powders, TiCN powder, TiC powder, TiN powder, Ta, each having a predetermined average particle size within the range of 1 to 3 μm
C powder, NbC powder, WC powder, Mo ₂ C powder, ZrC
Powder, Co powder, and Ni powder were used, and these raw material powders were blended to the blending composition shown in Table 1 and then mixed with a ball mill to produce 7
After wet mixing for 2 hours and drying, cermet substrates A to E
In regard to, the cermet substrate F ~ was pressed into a green compact having a shape conforming to ISO standard CNMG120408.
Regarding H, it was press-molded into a shape conforming to the standard SEEN1204AFTN1 and then the cermet substrate A
~ C, and F, G green compacts are sintered in a vacuum of 0.01 torr at a predetermined temperature in the range of 1450 to 1500 ° C for 1 hour, and cermet substrates D, E, and H. For the green compact of 0.01 to 0.01 to
A vacuum atmosphere of rr was used, and after reaching a predetermined sintering temperature within the range of 1450 to 1550 ° C., the atmosphere was kept as a N ₂ atmosphere of 10 torr for 1 hour, and cooling from the sintering temperature was 0.01
The cermet substrates A to H were manufactured by sintering under the conditions of performing in a torr vacuum (conditions for forming Co + Ni enriched zone on the surface of the cermet substrate).

Then, the surfaces of the cermet substrates A to H are subjected to finishing and honing, and the chemical vapor deposition adhesion bonding layers a to f are first used under the conditions shown in Table 2 using an ordinary chemical vapor deposition apparatus. One of the coating cermet cutting tools 1 to 12 of the present invention is formed by forming any one of them in the average layer thickness shown in Table 4 and further forming a hard coating layer having the composition and average layer thickness shown in Table 4. Manufactured.
Further, for the purpose of comparison, as shown in Table 5, the conventional coated cermet cutting tools 1 to 12 were manufactured under the same conditions except that the above chemical vapor deposition adhesion bonding layer was not formed. In addition, Table 3 shows the composition of each of the chemical vapor deposition adhesion bonding layers a to f.

Next, regarding the present invention and the conventional coated cermet cutting tools 1 to 8 obtained as a result, the work material: round bar of SCM440 (hardness: H _B 220), cutting speed: 270 m / min, feed : 0.25 mm / rev., Depth of cut: 1 mm, cutting time: 20 minutes, a wet high-speed continuous cutting test of steel was performed, and for the present invention and the conventional coated cermet cutting tools 9 to 12, the work material was: SCM440 square bar (hardness: H _B 220), cutting speed: 350m / min, feed: 0.25mm / rev., Depth of cut: 2mm, cutting time: 10 minutes, dry high-speed milling test of steel is performed. In each of the cutting tests, the flank wear width of the cutting edge was measured. Table 6 shows the measurement results.

[0010]

[Table 1]

[0011]

[Table 2]

[0012]

[Table 3]

[0013]

[Table 4]

[0014]

[Table 5]

[0015]

[Table 6]

[0016]

From the results shown in Tables 4 to 6, the coated cermet cutting tools 1 to 12 of the present invention are high-speed cutting in both continuous cutting and interrupted cutting, but the cermet substrate and the hard coating are used. By the action of the chemical vapor deposition adhesive bonding layer interposed between the layers, the hard coating layer does not peel, and exhibits excellent wear resistance, while the conventional coating without the chemical vapor deposition adhesive bonding layer formed. In the cermet cutting tools 1 to 12, it is clear that peeling occurs in the hard coating layer in both continuous cutting and intermittent cutting, and the service life is reached in a relatively short time. As described above, the coated cermet cutting tool of the present invention does not cause peeling in the hard coating layer even in high-speed cutting of steel or cast iron, and exhibits excellent wear resistance for a long period of time, so that the cutting machine has high performance. It is possible to satisfactorily deal with performance improvement and labor saving of cutting work.

Claims (1)

[Claims] 1. A titanium carbonitride-based cermet substrate, on the surface of which is formed a multilayer of two or more of Ti carbide, nitride, carbonitride, carbon oxide, carbonitride oxide, and aluminum oxide. A surface-coated titanium carbonitride-based cermet cutting tool comprising a hard coating layer having an average layer thickness of 0.5 to 20 μm. , Ni: 4 to 25%, Co: 15 to 50%, and a chemical vapor deposition adhesion bonding layer having a composition substantially consisting of titanium carbide or titanium carbonitride in an amount of 0.1 to 5 μm.
A surface-coated titanium carbonitride-based cermet cutting tool having an excellent tight bondability with a hard coating layer, characterized by being interposed with an average layer thickness of m.