JPS593541B2 - Coated cemented carbide parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to coated cemented carbide parts which have excellent wear resistance and are particularly suitable for use as cutting tools and wear-resistant parts.

Conventionally, as hard phase forming components, 4a, 5a.
Contains 60 to 97% by weight of one or more of carbides, nitrides, carbonitrides, } and carbonitrides of group 6a metals, and optionally as a binder phase forming component, In order to improve the wear resistance and plastic deformation resistance of the binder phase, one or more of Cr group metals, Si, and Al: 1 to 20% by weight is contained, and the residue is the binder phase. On the surface of a cemented carbide base material having a composition consisting of one or more iron group metals as forming components and unavoidable impurities, one or two metals of group 4a and group 5a of the periodic table are applied. an inner layer of carbides, nitrides, or carbonitrides of one or more metals and one of the group 4a and 5a metals of the periodic table;
A coated cemented carbide member formed by forming a hard coating layer composed of a face-centered cubic high-melting point compound consisting of a seed or an outer layer of carbonate, nitoxide, or carbonitoxide of two or more metals. is well known, and this conventional coated cemented carbide member has excellent wear resistance, so it is particularly applied as a throw-away chip, but this conventional coated cemented carbide member also has sufficient wear resistance. You can't expect sex,
Therefore, it is desirable to develop a coated cemented carbide member having even better wear resistance.

Therefore, the present inventors conducted research focusing on the conventionally coated cemented carbide members described above in order to obtain superalloyed members having better wear resistance from the above-mentioned viewpoints. The outer layer of the hard coating layer of the cemented carbide member is made of carbonate, nitride, or carbonitoxide of one or more metals from Groups 4a and 5a of the periodic table, or the like. One or more metals from Groups 4a and 5a and one or more carbonates, nitoxides, or carbonitoxides of boron and silicon (in this case boron and Silicon is dissolved in solid solution to improve the hardness and oxidation resistance of the outer layer, and its solid solution ratio is 0.001 as a proportion (molar ratio) to the total of carbon, nitrogen, and oxygen. It is composed of a face-centered cubic, high-melting point compound consisting of a compound with a solid solubility limit of 0.2 (from (a) The outer layer of the hard coating layer has various properties that vary from its surface to the inner layer bonding surface depending on the concentration gradient of solid solution oxygen.

(b) The composition of the outer layer at the joint surface with the inner layer can be freely selected from a composition that does not contain oxygen and has the strongest bonding force with the inner layer. (c) In a normal hard coating layer with a homogeneous composition that contains oxygen as a solid solution, if the layer thickness exceeds 2 to 3 μm, the particles will become coarse and become columnar crystals, but if there is a concentration gradient in the solid solution oxygen, grain growth will occur. is suppressed and a fine grain structure is ensured.

As a result, coated cemented carbide parts have excellent wear resistance and have been found to be able to be used, for example, as cutting tools under a wide range of usage conditions. It is.

This invention was made based on the above findings, and will be specifically explained below using Examples.

Example 1 94% by weight of tungsten carbide WC powder with an average particle size of 2 μm and 6% by weight of CO powder with an average particle size of 1 μm were wet-mixed in a ball mill for 24 hours, and a green compact was obtained from the mixed powder obtained by drying. molded, and this green compact was heated to a temperature of 140
Sintering was performed by holding at 0° C. for 1 hour to produce a cemented carbide base material.

Next, the above-mentioned cemented carbide base material was installed in a coating device equipped with a heat-resistant steel reaction tube inserted into a horizontal annular furnace, and equipped with a metal chloride vaporizer and various gas flow rate adjustment equipment. After heating to 1020°C in a non-oxidizing atmosphere, H2: 96%, TiCl: 2%, CH4: 2% (
A titanium carbide TiC coating layer as an inner layer was formed on the surface of the cemented carbide base material by flowing a reaction gas having a composition of
%. CH4: 1.95%, CO: 0.05% (volume%)
for 10 minutes, followed by a reaction gas having a composition of 10
A hard coating layer as an outer layer was formed on the inner layer by conducting a reaction for 2 hours while adjusting the reaction gas to increase CO by 0.05% and decrease CH4 by 0.05% every minute. An inventive coated superalloy member was produced.

The reaction gas composition at the end of the reaction was H2:96%, T
iCl4: 2.0%, CH4: 1.4%, CO: 0.6
% (volume %). When the cross section of the coated cemented carbide member of the present invention obtained as a result was observed, the layer thickness was 7 μm.
This hard coating layer has a uniform silvery white color from the bonding surface of the base material to a layer thickness of 4 μm, and changes to silvery gray toward the surface, X-ray analysis and X-ray microanalyzer analysis showed a face-centered cubic crystal, and the layer thickness was approximately 3.5μ from the bonding surface to the base material.
While no oxygen is detected up to the surface, the compositional formula: TiCO. 7OO. 3 was detected, and the oxygen concentration in the outer layer monotonically increased from the interface with the inner layer toward the surface.

Example 2 CIS made of the same cemented carbide base material as in Example 1
Using a throw-away chip and coating device in the shape of standard SNGN432, the conditions for titanium carbide TLC coating were as follows: reaction temperature: 1020°C, reaction gas composition: H2...96%, TiCl4:2
%, CH4: 2% (volume %), and titanium carbonate TiCO. 5OO. 5 Coating conditions: reaction temperature...1020'C, reaction gas composition...H2:97%, TiCl4:2%,
CO: 1% (volume %) was adopted, and the overall reaction time was 210%.
The first 20 minutes of this are carried out under TiC coating conditions to form a hard coating layer as an inner layer, and then for the remaining 190 minutes, one cycle is 10 minutes, and the first half of one cycle is covered with TiCO. ．． 5OO. A hard coating layer as an outer layer was formed by repeating 19 cycles under the conditions of 5 coating and TiC coating in the latter half.In this outer layer forming reaction, the reaction time of TiC coating in each cycle was set to 0.5 V) per cycle. While gradually shortening by 5 minutes, T
iCO. 5OO. 5 Coating reaction time per cycle 0
．． A coated cemented carbide member of the present invention was manufactured by performing an operation of increasing the length of time in 5 minute increments.

When the cross section of the coated cemented carbide member of the present invention obtained as a result was observed, it was found that it had a hard coating layer having a layer thickness of 9 μm and consisting of a fine granular structure as a whole, and this hard coating layer was not bonded to the base material. Layer thickness from the surface to about 2 μm is TiC as an inner layer,
From this point to the surface is TiCO as an outer layer. 5OO. 5
The solid solution oxygen content had a concentration gradient that monotonically increased from the inner layer bonding surface toward the surface.

Then, for the purpose of comparison, using the same cemented carbide base material and coating equipment, a TiC coating layer with a layer thickness of about 2 μm as an inner layer and a homogeneous composition as an outer layer was coated on the surface of the cemented carbide base material. TiCO. 5OO. A comparative coated cemented carbide member was manufactured in which a hard coating layer consisting of 5 coating layers was formed with a layer thickness of 9 μm.

Regarding the coated cemented carbide member of the present invention thus obtained and the comparative coated cemented carbide member, work material: FC25 round material (hardness HB: 250), cutting speed: 250 m/Min,
Depth of cut: 3m7! L, Feed: ・0.5m71L/Rev. When a cutting test was conducted under the conditions of , the life time of the coated cemented carbide member of the present invention was 16 minutes, the comparison coated cemented carbide member was 9 minutes, and the life time of the coated cemented carbide member of the present invention was excellent. It is clear that it has cutting properties.

Example 3 A throw-away chip of CIS standard SNGN432 of cemented carbide JIS-P3O was applied as the cemented carbide base material, and the same coating equipment as in Example 1 was used to coat titanium carbonitride TiCO. 4NO. 6 Coating conditions: Reaction temperature: 1000°C, reaction gas composition: H2: 60%, N2: 37%, Ti
Cl4: 2%, CH4: 1% (volume %), titanium carbonitride oxide 41C0.2N0.600
．． 2 Coating conditions: reaction temperature: 1000°C, reaction gas composition: H2: 60%, N2: 37%, Ti
Cl4: 2%, CO: 1% (volume %) were adopted, and the total reaction time was 150 minutes, of which the first 60 minutes were used as TiCO. 4NO. 6 coating conditions to form a hard coating layer as an inner layer, and then for the remaining 90 minutes, one cycle is 10 minutes, and the first half of one cycle is TiCO. 2NO. 6OO. 2 coats, T the second half
iCO. 4NO. A hard coating layer as an outer layer was formed by repeating 9 cycles under the condition of 6 coatings. During this outer layer forming reaction, TiCO. 2N
O. 6OO. 2 coating reaction time was increased by 1 minute per cycle, while the TiCO. 4NO. A coated cemented carbide member of the present invention was manufactured by performing an operation in which the reaction time of the coating was shortened by 1 minute per cycle.

When the cross section of the coated cemented carbide member of the present invention obtained as a result was observed using an X-ray microanalyzer, the layer thickness: 6
A hard coating layer with a thickness of about 3 μm is formed, and the hard coating layer has an inner layer of TiCO. 4NO. 6, the outer layer is TiCO. 2NO. 6OO. 2, and the solid solution oxygen in the outer layer monotonically increased from the inner layer bonding surface toward the surface.

Then, for comparison purposes, using the same cemented carbide substrate and coating equipment, TiCO. 4NO. 6 coating layer and a homogeneous composition TiCO.6 as outer layer. 2NO. 6O
O. A comparative coated cemented carbide member was manufactured in which a hard coating layer consisting of two coating layers was formed to have a layer thickness of 6 μm.

Regarding the coated cemented carbide member of the present invention and the comparative coated cemented carbide member thus obtained, the work material: JIS-SNCM
-8 (hardness HB: 300), cutting speed: 180m/Mi
n, depth of cut: 3m1L, feed: 0.4m7! L/Rev. When a cutting test was conducted under the following conditions, the service life of the coated cemented carbide member of the present invention: 15 minutes, and the comparative coated cemented carbide member: 10 minutes.

Example 4 Layer thickness: 4 μm on the surface of cemented carbide JIS standard P3O
In addition to using throw-out beef chips with a coating layer formed thereon, the coating device of Example 1 was further equipped with a gas flow rate adjusting device for boron trichloride and diglormethylsilane.
The throwaway chip was heated to 1020° C. in a non-oxidizing atmosphere in the coating device, and then H2: 95.6%, TiCl4: 2%, CH4: 1.9
5%, CO: 0.05%, BCl3: 0.2%, SiC
The reaction was carried out by flowing a mixed reaction gas consisting of H3/Cl2: 0.2% (volume %) for 10 minutes, and then CO was increased by 0.05% every 10 minutes, while CH4 was increased by 0.0%.
A coated cemented carbide member of the present invention was manufactured by reacting for 2 hours while reducing the amount by 5%.

When the cross section of the coated cemented carbide member of the present invention obtained as a result was observed, it was found that it had a hard coating layer with a layer thickness of 8 μm. Ti
C.O. 69OO. 28BO. O2SiO. Boron and silicon, which correspond to Ol, were detected, and the oxygen content monotonically increased from the inner layer bonding surface to the outer layer surface.

Claims (1)

[Scope of Claims] 1. As a hard phase forming component, one or more of carbides, nitrides, carbonitrides, and carbonitrides of metals from groups 4a, 5a, and 6a of the periodic table: 60 4a of the periodic table on the surface of a cemented carbide base material having a composition of 97% by weight and the remainder consisting of one or more iron group metals as binder phase forming components and unavoidable impurities. and an inner layer composed of a face-centered cubic high melting point compound consisting of carbides, nitrides, or carbonitrides of one or more metals of group 5a metals, and 4a and 5a of the periodic table.
Carbonates of one or more metals of group metals,
In the coated cemented carbide member formed by forming a hard coating layer consisting of an outer layer made of a face-centered cubic high melting point compound made of nitride oxide or carbonitride oxide, in the outer layer of the hard coating layer. A coated cemented carbide member characterized in that the solid solution oxygen content increases monotonically from the bonding surface with the inner layer toward the surface. 2 Contains 60 to 97% by weight of one or more of carbides, nitrides, carbonitrides, and carbonitrides of group 4a, 5a, and 6a metals of the periodic table as a hard phase forming component. Furthermore, as a bonding phase-forming component, one or more of Cr group metals, Si, and Al: 1-
20% by weight, and the remainder consists of one or more iron group metals as binder phase forming components and unavoidable impurities.
an inner layer composed of a face-centered cubic high melting point compound consisting of a carbide, nitride, or carbonitride of one or more metals of group a and group 5a metals, and 4a and 5a of the periodic table. Forming a hard coating layer consisting of an outer layer made of a face-centered cubic high melting point compound made of carbonate, nitride oxide, or carbonitride oxide of one or more metals in the group metals. A coated cemented carbide member characterized in that the solid solution oxygen content in the outer layer of the hard coating layer increases monotonically from the bonding surface with the inner layer toward the surface. . 3 Contains 60 to 97% by weight of one or more of carbides, nitrides, carbonitrides, and carbonitrides of group 4a, 5a, and 6a metals of the periodic table as a hard phase forming component. However, on the surface of a cemented carbide base material having a composition in which the remainder consists of one or more iron group metals as binder phase forming components and unavoidable impurities, metals from groups 4a and 5a of the periodic table are applied. 4a and 5a of the periodic table.
High melting point face-centered cubic crystal consisting of one or more metals from the group metals and one or two carbonates, nitrides, or carbonitoxides of boron and silicon In a coated cemented carbide member formed by forming a hard coating layer consisting of an outer layer made of a compound and A coated cemented carbide member characterized in that it increases monotonically. 4 Contains 60 to 97% by weight of one or more of carbides, nitrides, carbonitrides, and carbonitrides of group 4a, 5a, and 6a metals of the periodic table as a hard phase forming component. Furthermore, as a bonding phase-forming component, one or more of Cr group metals, Si, and Al: 1-
20% by weight, and the remainder consists of one or more iron group metals as binder phase forming components and unavoidable impurities.
an inner layer composed of a face-centered cubic high melting point compound consisting of carbides, nitrides, or carbonitrides of one or more metals of group a and group 5a metals, and 4a and 5a of the periodic table. one or more metals from the group metals;
Forming a hard coating layer consisting of an outer layer composed of a face-centered cubic high melting point compound made of one or two of boron and silicon carbonates, nitrides, or carbonitrides. A coated cemented carbide member characterized in that the solid solution oxygen content in the outer layer of the hard coating layer increases monotonically from the bonding surface with the inner layer toward the surface. .