JPH0417663A - Surface-coated hard parts for cutting tools and wear-resistant tools - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a surface-coated hard member that has improved wear resistance by providing a hard coating layer on the surface of a base material made of a cutting tool or a wear-resistant tool.

[Conventional technology]

Conventionally, cutting tools and wear-resistant tools are generally made of cemented carbide based on tungsten carbide (wC) or titanium carbide (Tie).
It is composed of various cermets such as thread, steel such as high-speed tool steel, hard alloys, and ceramics such as silicon carbide and silicon nitride.

In addition, in order to improve the wear resistance of these cutting tools and wear-resistant tools, a hard coating layer is applied to the surface using the PVD method or CV method.
Surface-coated hard members in which Ti, Hf, Zr (7) carbides, nitrides, carbonitrides, or oxides of Al are formed in a single layer or in multiple layers have been developed using the D method, and have recently been widely put into practical use. ing. In particular, the hard coating layer formed by the PVD method can improve wear resistance without deteriorating the strength of the base material, so it can be used in cutting applications that require strength, such as drills, end mills, and indexable inserts for milling. suitable for

However, although the PVD method is superior to the CVD method in that it can form a hard coating layer without deteriorating the strength of the base material,
Since it is difficult to stably form an oxide of Al using the D method, a hard coating layer made of an AI oxide formed using the PVD method has not been put to practical use. Also, Ti can be formed using the current PVD method.

Hard laminated layers of Hf, Zr carbides, nitrides, or carbonitrides cannot be said to have sufficient wear resistance, and many of them reach the end of their service life early due to lack of wear resistance, especially in high-speed cutting.

[Problem to be solved by the invention]

In view of such conventional circumstances, the present invention provides a cutting tool and a wear-resistant tool that maintains the strength of the base material of cutting tools and wear-resistant tools, and at the same time has superior wear resistance than conventional ones, particularly in high-speed cutting. An object of the present invention is to provide a surface-coated hard member for wear-resistant tools.

[Means to solve the problem]

In order to achieve the above object, the surface-coated hard member for cutting tools and wear-resistant tools of the present invention has a layer made of Zr carbide, nitride, or carbonitride on the surface of a base material made of cutting tools or wear-resistant tools. A hard coating layer in which 10 or more layers of carbide, nitride, or carbonitride are laminated alternately with a layer thickness of 0.01 to 0.2 μm to give a total layer thickness of 0.5 to 10 μm. It is characterized by having the following.

The hard coating layer may be provided on the entire surface of the cutting tool or wear-resistant tool that is the base material, or may be provided only on the surface of the cutting edge portion. Further, as a method for forming the hard coating layer, conventionally known methods can be used, but a Pv wing method such as a sputtering method or an ion blasting method is preferable since the strength of the base material can be easily maintained.

[Effect]

In the surface-coated hard member of the present invention, the hard coating layer is thin ZrC! , a layer of ZrN or ZrON and a thin Alc
.

It is composed of alternating layers of A/N or A10N, so when used as a cutting tool or a wear-resistant tool,
Combines excellent wear resistance, welding resistance, and chipping resistance,
Excellent cutting performance can be maintained over a long period of time.

That is, among the layers constituting the multilayer hard coating layer,
Carbide, nitride, or carbonitride of Zr increases the adhesion strength to the base material and the hardness of the hard coating layer. On the other hand, A
The carbide, nitride or carbonitride of Zr improves the fracture resistance of the hard coating layer, and at the same time refines the crystal grains by being dissolved in the layer of carbide, nitride or carbonitride of Zr.

Therefore, the synergistic action of these laminated layers improves the abrasion resistance, welding resistance, and chipping resistance of the hard coating layer as a whole.

Moreover, the surface-coated hard member used as a cutting tool or a wear-resistant tool having the above-mentioned hard coating layer has extremely high temperature hardness A in the hard coating layer due to an increase in the temperature of the cutting edge during cutting.
/O and ZrO were observed to be produced in small amounts,
Therefore, it was found that it exhibits good wear resistance even in high-speed cutting.

Regarding the layer thickness of the hard coating layer, the total layer thickness is 0.5 μm.
At less than 10 t, there is almost no improvement in wear resistance;
If it exceeds Im, the residual stress in the layer will increase and the adhesive strength with the base material will decrease, so the overall layer thickness should be reduced to 0.5 to 10μ.
The range is m.

In addition, it is difficult to form the layer thickness of the layer consisting of Zr carbide, nitride, or carbonitride and the layer consisting of KL carbide, nitride, or carbonitride to be thinner than 0.01 μm, which are laminated alternately. , if it is less than 0.01 μm, the entire laminated hard coating layer becomes brittle and wear resistance decreases. ! 15yi is 0
．． If the thickness exceeds 2 μm, the solid solution between the layers will not occur due to the thickness of each layer, and improvements in wear resistance, adhesion resistance, and chipping resistance due to synergistic effects will not be obtained. The thickness of each layer is in the range of 0.01 to 0.2 μm. Furthermore, even if the layer thickness of each of the above layers is in the range of 0.01 to 0.2 μm, if the number of alternately laminated layers is less than 10, the overall abrasion resistance, welding resistance, and resistance are still excellent. It is difficult to construct a hard coating layer that has defective properties.

〔Example〕

As the base material, the composition is JIS standard P30 (specifically w
A cemented carbide cutting tip with e -20 wt% Ti (! -10 wt% CO) and a shape of J Engineering S 5NG432 was prepared, and its surface was coated using the known ion blating method using vacuum arc discharge as described below. A hard coating layer shown in Table 1 was formed, and surface-coated cutting chip samples 1 to 4 of the present invention examples were prepared.
And so.

That is, a Zr target and A! The above-mentioned cutting tip is attached to a base metal holder that is placed facing the target and rotates between the two targets around the midpoint between the two targets, and holds the base metal so that the cutting tip rotates 20 times per minute. The rotation speed of V was adjusted. Thereafter, the inside of the film forming apparatus was maintained in an Ar gas atmosphere with a vacuum degree of 1×1 O −2 torr, and a voltage of −2000 V was applied to the cutting tip for cleaning. After heating to 500 C′, the Ar gas was exhausted. Next, while introducing one or both of N gas and CH gas into the film forming apparatus at a rate of 300 cc/min, the Zr target and Kl target are evaporated and ionized by vacuum arc discharge. While passing near the Zr target, Zr carbide,
The nitride or carbonitride was deposited and the carbide, nitride or carbonitride of the AI was deposited while passing near the A/target, alternating each layer. Z formed alternately
The layer thickness of each layer of r and Al carbide, nitride, or carbonitride was controlled by adjusting the amount of irradiated electron beam, and the overall layer thickness was controlled by coating time.

For comparison, conventional surface-coated cutting chip samples shown in Table 1 were also prepared. That is, in Samples 5 to 9, Tlc, T1N, and T1CN were deposited singly or in combination on the surface of a cutting tip having the same composition and shape as above by an ion blating method using a vacuum arc discharge using an ordinary film forming apparatus. Samples 8 and 9 were manufactured by coating the surfaces of cutting tips with the same composition and shape with TiC! by the usual CVD method. .

It was manufactured by forming a hard coating layer consisting of a combination of TiN, AI, and O.

Table 1 (Note) The x mark in the table indicates the conventional example (the same applies hereinafter).Next, continuous cutting tests and intermittent cutting tests were conducted under the following conditions for each surface-coated cutting chip sample manufactured as described above. The flank wear width of the blade was measured.

Cutting conditions Table 2 The results of each of the above cutting tests are shown in Table 2.

From the above results, among the conventional surface-coated cutting tip samples, samples 5 to 7, in which the hard coating layer was formed by the PVD method, were inferior in wear resistance, and samples 8 and 9, formed by the CVD method, had deteriorated toughness of the base material. In contrast, surface-coated cutting samples 1 to 4 of the present invention had excellent wear resistance in both continuous cutting and interrupted cutting, and at the same time had a hard coating layer. It can be seen that since it was formed by the PVD method, the toughness of the base material was maintained and it had excellent fracture resistance.

Note that each layer alternately laminated is ZrN and At as mentioned in the example.
In addition to the combination of all carbides, nitrides, or carbonitrides like N, and the combination of ZrN and AlCN, any combination can be used. For example, each layer of Zr and Al can also be combined. The material may be appropriately changed between carbide, nitride, and carbonitride during the lamination process.

〔Effect of the invention〕

According to the present invention, while maintaining the strength of the base material of cutting tools and wear-resistant tools, at the same time it has superior wear resistance than conventional ones, and it can be used as cutting tools and wear-resistant tools for a long period of time, especially in high-speed cutting. Cutting tools that can maintain cutting performance
A surface-coated hard member for wear-resistant tools can be provided.

1゜Procedural amendment (voluntary) Indication of the case 1990 Patent ljl No. 119191 3, Relationship between the person making the amendment and the case

Claims (1)

[Claims] (1) Z on the surface of the base material made of cutting tools or wear-resistant tools
A layer consisting of a carbide, nitride or carbonitride of r and a layer consisting of a carbide, nitride or carbonitride of Al are each 0.0
A surface-coated hard member for cutting tools and wear-resistant tools, characterized by having a hard coating layer that is alternately laminated in 10 or more layers with a layer thickness of 1 to 0.2 μm to have a total layer thickness of 0.5 to 10 μm.