JPH0679543A - Manufacture of cutting tool made by compositely covering hard layer and stainless steel layer - Google Patents

Abstract

PURPOSE:To improve the chipping resistance extensively without reducing the abrasion resistance by shot blasting stainless steel balls to a hard layer covered cutting tool made by using a WC radical hard alloy or a TiCN radical sermet as a base substance, and covering a special hard layer to the surface of the base substance. CONSTITUTION:By using a WC radical sintered hard alloy or a TiCN radical cermet as a base substance, and covering a hard layer which consists of one sort, or two sorts or more of TiC, TiN, TiCN, TiCO, TiCNO, and Al2O3 to the surface of the base substance, a hard layer covered cutting tool is obtained. By shot blasting stainless steel balls to the above tool, a tool with an excellent strength and an excellent abrasion resistance can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a cutting tool having a hard layer and a stainless steel layer coated together.

[0002]

2. Description of the Related Art Conventionally, a WC-based cemented carbide is used as a substrate, the surface of which is coated with TiC, TiN, and TiCN, and then A
l ₂ O ₃ and then Ti, Zr, Hf,
One metal selected from the group consisting of V, Nb, Ta, Cr, Mo, W, Fe, Co, and Ni or an alloy composed of two or more of the above metals is chemically vapor deposited (hereinafter, referred to as C).
VD method), physical vapor deposition method (hereinafter referred to as PVD method), electroless plating method and the like, the method of manufacturing a cutting tool formed by composite coating hard layer and metal layer,
For example, it is also described in JP-A No. 52-100309.

[0003]

However, the above-mentioned Ti, Z
r, Hf, V, Nb, Ta, Cr, Mo, W, Fe, C
When a metal such as o or Ni is coated by the PVD method, the coating is performed in a high vacuum. Therefore, after coating, the coating layer oxidizes and becomes brittle, and the fracture resistance decreases when intermittent cutting is performed. There was a problem.

[0004]

Therefore, the present inventors have
As a result of research to develop a hard layer-coated cutting tool that is resistant to chipping even when severely interrupted cutting, and has excellent strength and wear resistance, the results show that CVD is applied to the surface of WC-based cemented carbide or TiCN-based cermet substrates. Method, PVD method or TiC, TiN, TiCN, TiCO, TiCNO, A
A hard layer-coated cutting tool obtained by coating a hard layer (hereinafter, referred to as a hard layer) made of one or two or more of l ₂ O ₃ is used for a metal ball made of stainless steel (hereinafter, stainless steel ball). It has been found that when a shot blasting is performed, a coating layer of stainless steel is formed on the surface of the cutting tool coated with a hard layer, and the strength and wear resistance are improved.

The present invention was made on the basis of such findings, and (1) uses a WC-based cemented carbide as a base,
A hard layer-coated cutting tool having a surface coated with a hard layer, a method for producing a cutting tool having a hard layer for shot blasting a stainless steel ball and a stainless steel layer coated together, and (2) TiCN-based cermet Characterized by a hard-layer-coated cutting tool having a surface coated with a hard layer, and a hard-layer coated with a hard layer and a stainless steel layer coated by shot-blasting stainless steel. Is.

[0006]

EXAMPLES Next, a method of manufacturing a coated cutting tool according to the present invention will be specifically described based on examples.

Example 1 A normal W obtained by sintering a green compact having the shape of ISO standard SNMG120408 and having the composition shown in Table 1 was used.
C-based cemented carbide (hereinafter referred to as cemented carbide) A to C were prepared.

[0008]

[Table 1]

The cemented carbides A to C shown in Table 1 were used as substrates, and the coating layers shown in Table 2 were formed on the surface of the substrates by the ordinary CVD method to produce coated cutting tools a to f.

[0010]

[Table 2]

The coated cutting tools a to f had a diameter of 0.3.
Projection speed of 60 mm SUS304 stainless steel ball: 60
A stainless steel layer was formed by performing shot blasting at 70 m / min for 70 seconds to produce a composite coated cutting tool according to Manufacturing Methods 1 to 6 of the present invention.

Conventional Example 1 The coated cutting tools a to f prepared in Example 1 were made of ordinary PVD.
A stainless steel layer was formed by the method to produce a composite coated cutting tool according to the conventional manufacturing methods 1 to 6.

The composite coated cutting tools obtained by the above-mentioned production methods 1 to 6 of the present invention, the composite coated cutting tools obtained by the conventional production methods 1 to 6 and the composite coated cutting tools obtained by the conventional production methods 7 to 12 are Work material: SCM440 (hardness HB 240) round bar Cutting speed: 220 m / min, feed: 0.3 mm / rev. , Depth of cut: 1.0 mm, cutting time: 30 min. A continuous cutting test was performed under the condition of no cutting oil: the flank wear width of the composite coated cutting tool was measured to evaluate the wear resistance.

Work material: SNCM439 (hardness HB 270) square material Cutting speed: 100 m / min, Feed: 0.375 mm / rev. An intermittent cutting test was performed under the following conditions: depth of cut: 1.5 mm, cutting oil: none, and the cutting time until the cutting edge of the composite coated cutting tool was broken was measured to evaluate fracture resistance. The results of these measurements are shown in Tables 3 and 4.

[0015]

[Table 3]

[0016]

[Table 4]

From the results shown in Tables 3 and 4, the composite coated cutting tools obtained by the production methods 1 to 6 of the present invention are particularly superior to the composite coated cutting tools obtained by the conventional production methods 1 to 12. It can be seen that the chipping resistance is excellent.

Example 2 A normal T obtained by sintering a green compact having the shape of ISO standard SNMG120408 and having the composition shown in Table 5 was used.
iCN group cermet (hereinafter referred to as cermet) D to E
Prepared.

[0019]

[Table 5]

Cermets D to E shown in Table 5 were used as substrates, and hard layers shown in Table 6 were formed on the surface of the substrates by a normal CVD method to produce coated cutting tools g to j.

[0021]

[Table 6]

The coated cutting tools g to j had a diameter of 0.3.
Projection speed of 60 mm SUS304 stainless steel ball: 60
A stainless steel layer was formed by performing shot blasting with 80 seconds of projection at m / min, and a composite coated cutting tool according to the production methods 7 to 10 of the present invention was produced.

Conventional Example 2 The coated cutting tools g to j produced in Example 2 were made of ordinary PVD.
Forming a stainless steel layer by the conventional method
A composite coated cutting tool according to No. 6 was produced.

Using the composite coated cutting tool obtained by the manufacturing method 7 to 10 of the present invention and the composite coated cutting tool obtained by the conventional manufacturing method 7 to 10, a work material: SCM440 (hardness HB 220) round bar Cutting speed: 200 m / min, feed: 0.25 mm / rev. , Depth of cut: 1.0 mm, cutting time: 30 min. A continuous cutting test was performed under the condition of no cutting oil: the flank wear width of the composite coated cutting tool was measured to evaluate the wear resistance.

Work material: SCM439 (hardness HB 220) round bar with groove Cutting speed: 200 m / min, Feed: 0.25 mm / rev. An intermittent cutting test was performed under the following conditions: depth of cut: 1.0 mm, cutting oil: none, and the cutting time until the cutting edge of the composite coated cutting tool was broken was measured to evaluate the breakage resistance. The measurement results are shown in Tables 7 to 8.

[0026]

[Table 7]

From the results shown in Table 7, the production method 7 of the present invention
It can be seen that the composite coated cutting tools obtained by Nos. 10 to 10 are particularly excellent in fracture resistance as compared with the composite coated cutting tools obtained by the conventional manufacturing methods 7 to 10.

[0028]

Therefore, according to the method for manufacturing a cutting tool of the present invention, in which the hard layer and the stainless steel layer are coated together, the fracture resistance is significantly improved as compared with the conventional one without lowering the wear resistance. It is possible to obtain a surface-coated cutting tool, which greatly improves the tool life and has an excellent industrial effect.

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[Procedure amendment]

[Submission date] October 7, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

The coated cutting tools a to f had a diameter of 0.3.
Projection speed of 60 mm SUS304 stainless steel ball: 60
A stainless steel layer was formed by performing a shot blast of 70 seconds projection at m / sec to produce a composite coated cutting tool according to Manufacturing Methods 1 to 6 of the present invention.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0015

[Correction method] Change

[Correction content]

[0015]

[Table 3]

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

The coated cutting tools g to j had a diameter of 0.3.
Projection speed of 60 mm SUS304 stainless steel ball: 60
A stainless steel layer was formed by performing shot blasting with 80 msec projection at m / sec , and a composite coated cutting tool according to the production methods 7 to 10 of the present invention was produced.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

[0026]

[Table 7]

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display area C23C 28/00 B

Claims (2)

[Claims] 1. A WC-based cemented carbide substrate as a substrate, on the surface of which TiC, TiN, TiCN, TiCO, TiCNO, A
Hard layer characterized by shot blasting a stainless steel ball to a hard layer-coated cutting tool coated with a hard layer (hereinafter referred to as a hard layer) consisting of one or more of l ₂ O _3. And a method for manufacturing a cutting tool comprising a composite coating of a stainless steel layer. 2. A composite coating of a hard layer and a stainless steel layer, characterized in that a hard layer-coated cutting tool comprising a TiCN-based cermet as a substrate and a hard layer coated on the surface is shot-blasted with a stainless steel ball. A method for manufacturing a cutting tool.