JPH03120353A - Surface coated super hard member for cutting or wear resistant tool - Google Patents

Abstract

PURPOSE:To maintain the strength of a base material and to improve wear resistance at the time of high speed cutting by alternately forming a TiN layer and an AlN layer of respectively specified thicknesses on the surface of a base material into plural layers. CONSTITUTION:A TiN layer and an AlN layer having 0.01-0.2mum layer thickness, respectively, are alternately formed on the surface of a base material made of sintered hard alloy, etc., for cutting or wear resistant tool into >=10 layers by an ion plating method, etc. The thickness of the above coating layers as a whole is regulated to 0.5-8mum. This surface coated super hard member has superior wear resistance, deposition resistance, and breaking resistance and shows excellent machinability over a long period as a cutting tool or a wear resistant tool in high speed cutting as well as in low speed cutting.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a surface-coated carbide member for cutting and wear-resistant tools, which has improved wear resistance by providing a coating layer on the surface of the cutting tool or wear-resistant tool. .

[Conventional technology]

Conventionally, the materials used for cutting tools and wear-resistant tools include cemented carbide such as tungsten carbide (WE), various cermets such as titanium carbide (TiC), steel and hard alloys such as high-speed tool steel, silicon carbide and silicon nitride. The main products were ceramics such as

In addition, in order to improve the wear resistance of cutting tools and wear-resistant tools, the entire surface or the surface of the cutting edge is coated with physical vapor deposition (PVD) or chemical vapor deposition (CVN). , titanium (Tt), hafnium (Hf), zirconium (Zr) carbides, nitrides, or carbonitrides, or aluminum (A) oxides, etc., have been developed in a single or multilayer surface-coated hard member. In recent years, cutting tools and wear-resistant tools with a coating layer formed by the PVD method can improve wear resistance without degrading the strength of the base material, so they can be used for drilling, end mills, and milling. Suitable for cutting applications that require strength, such as indexable inserts.

However, although the PVD method is superior to the CVN method in that it can form a coating layer without deteriorating the strength of the base material, I'VD
Since it is difficult to stably coat the base material with Al oxide using the PVD method, the A/oxide coating layer has not been put into practical use. Coating layers made of nitrides, carbonitrides, etc. often reach the end of their service life early because of their lack of wear resistance, especially during high-speed cutting.

[Problem to be solved by the invention]

In view of such conventional circumstances, the present invention maintains the strength of the base material of cutting tools and wear-resistant tools, and at the same time provides a coating layer with excellent wear resistance, thereby improving wear resistance compared to conventional ones, especially in high-speed cutting. The purpose of the present invention is to provide a surface-coated carbide member for cutting and wear-resistant tools.

[Means to solve the problem]

In order to achieve the above object, in the surface-coated carbide member for cutting and wear-resistant tools of the present invention, a layer of TIN with a thickness of 0.01 to 0.2 μm is coated on the surface of the base material of the cutting tool or the wear-resistant tool.
Alternately stack 10 or more layers of AIN and AIN to create a total layer thickness of 0.5
It is characterized by providing a coating layer of ~8 μm.

The coating layer may be provided on the entire surface of the cutting tool or wear-resistant tool, or may be provided only on the surface of the cutting edge portion. Although conventionally known methods can be used to form the coating layer, PVD methods such as sputtering and ion blasting are preferred because the strength of the base material can be easily maintained.

[Effect]

As a cutting tool or a wear-resistant tool, the surface-coated carbide member of the present invention has excellent wear resistance, adhesion resistance, and chipping resistance not only in low-speed cutting but also in high-speed cutting, and exhibits excellent cutting performance over a long period of time.

The reason for this is that by alternately laminating thin TiN and AtN layers on the surface of the base material, TiN increases the hardness of the coating layer and improves its adhesion to the base material, while AIN improves the fracture resistance of the coating layer. The TiN layer and the AtN layer work synergistically to improve the wear resistance and make the TiH crystal grains finer, resulting in excellent wear resistance, welding resistance, and chipping resistance as a whole. This is thought to be because it becomes a covering layer.

The thinner the layer thicknesses of the TiN layers and AtN layers stacked alternately are, the better; however, it is difficult to form the layers thinner than 0.01 μm using normal methods, and if the thickness exceeds 0.2 μm, each TiN layer and AtN layer becomes thicker. 0.01 to
The range is 0.2 μm. Furthermore, even if the number of laminated TiN layers and AtN layers is less than 10, a coating layer having excellent wear resistance, adhesion resistance, and chipping resistance as a whole cannot be obtained due to the above-mentioned interaction.

The thickness of the entire coating layer is 0.5 to 8 μm.
This is because if the thickness is less than 8 μm, no improvement in wear resistance is observed due to the coating layer, and if it exceeds 8 μm, the residual stress in the coating layer increases and the adhesion strength with the base material decreases.

〔Example〕

As a base material, a cemented carbide cutting tip with a composition of TIS standard P30 (specifically, WC-20wt%Tie-10wt%Co) and a shape of the same SNG432 was prepared, and its surface was heated with a vacuum arc as shown below. A coating layer shown in Table 2 below was formed by an ion blating method using electric discharge to obtain a coated cutting chip sample of an example of the present invention.

That is, a Ti target and an Al target are placed facing each other in a film forming apparatus, and two points on the diameter passing through the center of a ring-shaped base material holding jig that rotates around the midpoint between the two targets, The above-mentioned cutting tips, which were base materials, were respectively attached. In this state, while rotating the cutting tip at 20 rpm, the inside of the film forming apparatus was heated to an Ar gas with a vacuum level of 1X10""torr.
Maintaining the gas atmosphere, apply a voltage of -2000V to the surface cutting tip to clean it, heat it to 500σ, and then apply Ar
Exhausted the gas. After that, while controlling the rotation of the cutting tip, N gas was introduced into the film forming apparatus at a rate of 300 cc/min, and the T1 target and Al were heated by vacuum arc discharge.
By evaporating and ionizing the targets together, TiN is formed on the cutting tip when the cutting tip passes near the T1 target and AIN is formed on the cutting tip when passing near the Al target, so that a TiN layer is formed on the surface of each cutting tip. and AtN layers were alternately stacked. The layer thickness of each TiN layer and AtN layer to be laminated was controlled by adjusting the amount of arc current, and the layer thickness of the entire coating layer was controlled by the film formation time.

For comparison, TiC and TiN5 were deposited on the surface of a cutting tip with the same composition and shape as above using an ion blating method using vacuum arc discharge using an ordinary film forming apparatus.
A multi-layer coating layer was formed by combining TiON, and conventional coated cutting chip samples shown in Table 2 below were manufactured. A coated cutting chip sample was also prepared in which a coating layer of TiC, At 2 O, etc. shown in Table 2 below was formed on the surface of a cutting chip having the same composition and shape by a conventional CVD method.

For each coated cutting chip sample having the obtained coating layer, a continuous cutting test and an intermittent cutting test were conducted under the conditions shown in Table 1 below to measure the flank wear width of the cutting edge, and the results are also shown in Table 2. displayed.

From the above results in Table 1, it can be seen that the coated cutting tip sample of the present invention has excellent wear resistance and chipping resistance in both rapid cutting and interrupted cutting, and is superior to that of the conventional example. It can be seen that the cutting performance is shown.

〔Effect of the invention〕

According to the present invention, there is provided a surface-coated carbide member for cutting and wear-resistant tools that has excellent wear resistance and chipping resistance not only in low-speed cutting but also in high-speed cutting, and can maintain excellent cutting performance over a long period of time. 0 1゜Indication of the case that can be made Heisei Unified Patent Amendment Application (Spontaneous) No. 254492'& Person making the amendment Relationship with the case

Claims (1)

[Claims] (1) Ten or more TiN layers and AlN layers with a layer thickness of 0.01 to 0.2 μm are alternately laminated on the surface of a base material consisting of a cutting tool or a wear-resistant tool, so that the total layer thickness is 0.5 to 8 μm. A surface-coated carbide member for cutting and wear-resistant tools characterized by providing a coating layer.