JPS59229479A - Production of surface coated sintered hard member for cutting tool - Google Patents

Abstract

PURPOSE:To obtain a titled member which provides excellent cutting performance by introducing a reactive gaseous mixture contg. an Al supply source, CO2 and/or CO to a base member consisting of a sintered hard member or surface coated sintered hard member in a reaction vessel and performing plasma chemical vapor deposition treatment under prescribed conditions. CONSTITUTION:A base member constituted of cermet such as a WC-base sintered hard alloy or ceramics such as an Al2O3-base sintered material is charged into a reaction vessel. A reactive gaseous mixture composed of 0.5-5% one kind of an Al supply source such as AlCl3, Al(CH3)3, etc., 3-15% CO2 or/and CO or these and gaseous hydrocharbon, 10-30% N2, 30-70% Ar and the balance H2 is introduced into the reaction vessel. A plasma chemical vapor deposition treatment is then performed under the conditions of 0.1-20 Torr atmosphere in the reaction vessel, impression of -300--900V DC voltage on the base member or high frequency electric power of 0.2-10W/cm<2> and 800-1,200 deg.C heating temp. in the reaction vessel. As a result, the titled sintered member which consists of AlCNO, has high hardness and toughness and is extremely stable chemically is obtd. on the surface of the base member.

Description

[Detailed Description of the Invention] This invention provides an excellent cutting tool when used as a cutting tool for cutting steel and cast iron, especially for heavy cutting such as high-speed cutting of these corrugated materials, high-speed cutting, and deep cutting. The present invention relates to a method for manufacturing a surface-coated ultra-hard sintered member that exhibits cutting performance.

Conventionally, the base member is generally an ultra-hard sintered member made of a cermet such as a tungsten carbide-based cemented carbide or a titanium carbide-based sintered material, or a ceramic such as an aluminum oxide-based sintered material. On the surface, 4a and 5a of the periodic table.

A coating layer consisting of a single layer or a multilayer of two or more of the group 6a metal carbides, nitrides, and oxides, and solid solutions of two or more of these metals is formed by chemical vapor deposition or the like. It is well known that surface-coated ultra-hard sintered members with multiple shapes are used as cutting tools.

However, although some of these conventional surface-coated ultra-hard sintered members show excellent cutting performance when used for cutting steel, they do not show the desired cutting performance when cutting cast iron, and it takes a relatively short time. Others, on the contrary, show excellent performance and a relatively long service life when cutting cast iron, but have a short cutting life when cutting steel. Paddles, etc., do not exhibit satisfactory cutting performance when cutting either steel or cast iron, and even more so when performing heavy cutting such as high-speed cutting of these corrugated materials, high-feed cutting, and deep-cut cutting. Of course, this is true when cutting under such severe conditions.

Therefore, from the above-mentioned viewpoint, the present inventors believe that it can be used for cutting both steel and cast iron, and that it can be used under harsh conditions such as high-speed cutting and heavy cutting of these rigid materials. As a result of research to develop a cutting tool that exhibits excellent cutting performance even when cutting with Charge into the container, and at the capacity section, AQCt3. AQ(CH3)3, and AP,2
One of (CH3)3Ct3 (hereinafter collectively referred to as AM source): 0.5 to 5%.

One or two of CO2 and CO: 3-15%
, or one or two of CO2 and Co, and hydrocarbon gas: 3 to 15% (however, hydrocarbon gas 20%
(hereinafter collectively referred to as carbon/oxygen supply source).

N2: 1 0-30 Chi.

Ar: 30-70%.

H2: Residue (contains 10% or more).

While introducing a reaction mixture gas having a composition consisting of: heating temperature in the reaction vessel 〇, vacuum of 1 to 20 torr.

DC voltage of 300 to -800 V applied to the base member,
Or high frequency power of 02~10W/crl.

Heating temperature inside the reaction vessel = 800-1200°C.

When plasma chemical vapor deposition treatment is performed under the following conditions, crystalline aluminum carbonitoxide (hereinafter referred to as
A hard coating layer consisting of AQCNO (denoted as A11CNO) is formed, and this AQCNO has high hardness at room temperature and high temperature, high toughness, and is extremely chemically stable at high temperature. Therefore, the surface-coated ultra-hard sintered member formed with the AA CN O hard coating layer exhibits excellent performance when used as a cutting tool for cutting steel and cast iron. Can be used for high-speed cutting and heavy cutting of corrugated materials 5
- We have found that it can also exhibit excellent cutting performance and ensure a long service life.

This invention was made based on the above knowledge, and the reason why the manufacturing conditions were limited to the above general conditions will be explained below.

(a) Composition of reaction mixture ■ Ae supply source, carbon/oxygen supply source, and N2 The blended amounts of these components are less than 20.5 g of Al source and less than 23 g of carbon/oxygen source, respectively. , and N2: less than 10%, Afi-CNO in crystalline form at practical reaction rates.
A hard coating layer cannot be formed on the surface of the base member,
On the other hand, when the blended amount of AP and supply source exceeds 5 ml, the reaction within the glow discharge becomes active and AQ-CNO powder is formed, resulting in AFI being firmly deposited on the surface of the base member. It is difficult to form a CN O hard coating layer, and when the carbon/oxygen supply source exceeds 15%, N2
If it exceeds 30 cm, AA203 and AeN will be mixed in the AQ CN O hard coating layer, and the properties of the coating layer will deteriorate. AQ
Supply source: 0.5 to 5, carbon/oxygen supply source: 3 to 15%
, and N2: 10-3o. Note that hydrocarbon gas is blended when it is necessary to relatively increase the C component in the AQCNO hard coating layer, but if the blended amount is 0.
If the amount is less than 3%, the effect will not appear, while if it is more than 5%, graphite (carbon) will precipitate, which will similarly deteriorate the properties of the hard coating layer. The amount of gas blended was determined to be 0.3 to 5 inches.

■ Ar Ar gas has the effect of promoting glow discharge, but if the amount is less than 30%, the desired glow discharge cannot be achieved, while if it is more than 70%, glow discharge becomes active. If the surface temperature of the base member is too high, exceeding 1200°C, the crystal grains of the hard coating layer will become coarse and brittle. It is determined that

Note that if the amount of N2 is less than 10%, the reduction of the AC supply source will not be carried out sufficiently, and as a result, it will take a long time to form the Ag CN O hard coating layer.
The blending amount was set at 10'% or more.

■ Pressure of the atmosphere inside the reaction vessel If the pressure is less than 0.1 torr, the reaction rate is extremely slow and impractical; on the other hand, if the pressure exceeds 20 torr, a reaction occurs in the atmosphere, resulting in non-performance. The pressure was set at 0.1 y 20 torr since crystalline AP, CN 2 O powder was formed.

(C) Application to the base member When the application to the base member is a DC voltage: less than -300V, and when high frequency power is applied: less than 0.2 W/i, the glow discharge is extremely weak and the desired Ag, CN O coating is not achieved. It is not possible to form a layer, and - at the actual DC voltage, it is -5oo
v. In the case of high-frequency power, if IOW/ffl is exceeded, the temperature of the base member will be too high, exceeding 1200°C, and crystal grain growth, which causes embrittlement, will increase significantly. When applying DC voltage, the knee is 300~
-5oov, for high frequency power: 0.2~IOW/ff
It was determined as l.

O) Heating temperature in the reaction vessel If the heating temperature is less than 800°C, the AACNO coating layer becomes amorphous and cannot form a crystalline form.On the other hand, if the heating temperature exceeds 1200°C, the above-mentioned As mentioned above, grain growth that causes embrittlement occurs in the A1ICN O coating layer, so the heating temperature is set to 800-1
The temperature was set at 200°C.

It should be noted that it can be easily confirmed by X-ray diffraction measurement that the AQCNO hard coating layer formed by the method of the present invention has a crystalline form, and furthermore, it has an atomic ratio of AA 0.55 to 0.6100. .15~0.22NO,
It has a composition of 02-o, oeoo, x3-020.

Furthermore, when forming the AlICN0 coating layer by the method of this invention, the average layer thickness is 0.5 to 20 μm.
It is desirable that the average layer thickness is 0.5μ.
If the layer thickness is less than 20 μm, the desired excellent cutting performance cannot be achieved over a long period of time. On the other hand, if the layer thickness exceeds 20 μm, the coating process time becomes longer, resulting in coarse grained crystals and poor toughness. This is because not only does the surface temperature become lower than 9 -, but also the surface becomes rough and uneven.

Next, the method for manufacturing the surface-coated ultra-hard sintered member of the present invention will be specifically explained using examples.

A cutting tip made of an ultra-hard sintered material and a cutting tip made of a surface-coated ultra-hard sintered material each having the composition and coating layer shown in Table 1 were prepared as the base member of the example, and each of these base members was The base member is charged into a reaction vessel of a plasma chemical vapor deposition apparatus, and then subjected to plasma chemical vapor deposition treatment under the conditions shown in Table 1 to coat the surface of the base member with M.
Surface-coated cutting tips 1-12 of the present invention were each manufactured by forming a CNO hard coating layer.

Next, the surface-coated cutting chip of the present invention obtained as a result]
Composition of the All CN O coating layer in , ~12.

The crystal shape, Vickers hardness and average layer thickness were measured and the results are also shown in Table 1.

Furthermore, regarding the above-mentioned surface-coated cutting tips 1 to 12 of the present invention, 10-2nd surface cut material: SNCM-8 (hardness: HB270).

Cutting speed: 160 m/mXL.

Sending: 0.34 run/rev.

Depth of cut: 1.5M.

Cutting time: 30 mm.

High-speed cutting test of steel under the conditions of and work material: FC-
25 (hardness: HB200).

Cutting speed: 2Q Om/rm.

Sending: 025/rev.

Depth of cut: 1.5B.

Cutting time: 20 min.

A high-speed cutting test was conducted on cast iron under the following conditions, and the flank wear width of the cutting edge was measured after the test. The results of these measurements are shown in Table 2. Table 2 also shows, for comparison purposes, the surface-coated cutting tips 1 to 12 of the present invention, respectively.
Also shown are the cutting test results of the base member (hereinafter referred to as conventional cutting tips 1 to 12) before forming the CN O coating layer under the same conditions.

From the results shown in Table 2, surface-coated cutting chips 1 to 12 of the present invention can be used for high-15-heavy cutting of both steel and cast iron, respectively, compared to conventional cutting chips that are the same except that they do not form an AtICN0 hard coating layer. 〜12, showing much better wear resistance than AtlCN○
It is clear that this is caused by the formation of a hard coating layer.

As described above, according to the method of the present invention, an AQ CN Q hard coating layer that has high hardness and toughness at room temperature and high temperature, and is chemically stable at high temperature is formed on the surface of the base member. can, therefore,
When this surface-coated ultra-hard sintered member with an AACNO hard coating layer is used as a cutting tool for cutting steel and cast iron, it exhibits excellent performance. It consistently exhibits excellent cutting performance over a long period of time, even in cutting and heavy cutting.

Applicant: Mitsubishi Metals Corporation Agent Tomi 1) Kazuo and 1 other person 161

Claims (1)

[Claims] A base member is an ultra-hard sintered member made of cermet or ceramics, or a surface-coated ultra-hard sintered member formed by forming a hard layer on the surface of the ultra-hard sintered member; Charge the members into the reaction vessel, and in the capacity section, AeC23, AQ(CH3)3. and AQ2(CH3
)3 One type of C1s: 0.5-5%. One or two of CO2 and CO = 3 to 15%, or one or two of CO2 and Co and hydrocarbon gas: 3 to 15% (however, if hydrocarbon is 220
．． 3-5%). N2: l 0-30%. 1-Ar: 30-70%. N2: Remaining (contains 10% or more). While introducing a reaction mixture gas having a composition consisting of: a vacuum at a heating temperature of 0.1 to 20 torr in the reaction vessel; DC voltage of 300 to -800v applied to the base member,
! , or a high frequency power of 0.2 to lOW/d. Heating temperature inside the reaction vessel = 800-1200°C. A surface-coated ultra-hard sintered member for a cutting tool, characterized in that a hard coating layer made of crystalline aluminum carbonitride oxide is formed on the surface of the base member by performing plasma chemical vapor deposition treatment under the following conditions. manufacturing method.