JP3463459B2 - Surface-coated tungsten carbide based cemented carbide cutting tool with excellent fracture resistance with hard coating layer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention
Surface coated tungsten carbide based with breakage resistance
For hard alloy cutting tools (hereinafter referred to as coated carbide cutting tools)
It is about. [0002] 2. Description of the Related Art Conventionally, tungsten carbide based carbide
Chemical vapor deposition on the surface of an alloy substrate (hereinafter referred to as a carbide substrate)
Ti carbide (hereinafter referred to as TiC)
) Layer, nitride (hereinafter referred to as TiN) layer, carbonitriding
(Hereinafter referred to as TiCN) layer, carbonate (hereinafter referred to as Ti
CO) layer, nitric oxide (hereinafter referred to as TiNO)
Layer and carbonitride (hereinafter referred to as TiCNO) layer
(Hereinafter, these are collectively referred to as the carbon / nitride / oxide layer of Ti.
And aluminum oxide (hereinafter referred to as A)
l_TwoO_ThreeThe hard coating layer composed of
Coated carbide cutting tool formed with an average layer thickness of ~ 20 µm
It is known that this coated carbide cutting tool can be
Also used for continuous and interrupted cutting of cast iron
It is well known. Also, Japanese Patent Application Laid-Open No. 57-578
No. 65, the hardness of a coated carbide cutting tool
Constituting the porous coating layer_TwoO_ThreeWhen forming a layer,
In order to increase the speed and enable thick film formation,
Use of a reaction gas containing yellow (S) has also been performed.
I have. [0003] On the other hand, cutting in recent years
There is a strong demand for higher efficiency and labor saving,
No cutting speed is high and high feed and high depth of cut
Although there is a tendency for heavy cutting, the above conventional coated carbide cutting
In the tool, the hard coating layer constituting this _TwoO_Three
If the layer is formed into a thick film using an S-containing reaction gas,
If the above Al_TwoO_Three0.01-0.2 atomic% of the layer
The S component is contained, and as a result, the S-containing Al
_TwoO_ThreeEmbrittlement of the layers is inevitable, which results in high toughness
Heavy cutting required, eg high feed and high depth of cut
When used for intermittent cutting of chips, chipping or chipping (fine
Small chipping) easily occurs, and the service life is reached in a relatively short time
is the current situation. [0004] Means for Solving the Problems Accordingly, the present inventors have
From the viewpoint as described above, A constituting the above-mentioned hard coating layer
l_TwoO_ThreeThe layer contains 0.01-0.2 atomic% of S component
Focusing on conventional coated carbide cutting tools,_TwoO_Threelayer
As a result of research to prevent the embrittlement of Al,
_TwoO_ThreeThe layer is coated with the S-containing Al_TwoO_ThreeAt least one of the layers
And Ti-containing Al containing 0.3 to 2 atomic% of Ti_TwoO
_ThreeAl comprising at least two alternate layers of layers_TwoO_Threesystem
When composed of multiple layers, the resulting Al_TwoO_ThreeSystem multilayer
Is the S-containing Al_TwoO_ThreeThick film is possible by unit layer
And the Ti-containing Al_TwoO _ThreeTough by unit layer
The improvement of the property is achieved, and therefore, the Al_Two
O_ThreeSystem multi-layer and the Ti carbon / nitride / oxide layer
Coating formed by forming a hard coating layer composed of at least one kind
Carbide cutting tools are used for high feed and high cutting where high toughness is required.
Even when performing heavy cutting such as cutting with intermittent cutting,
Al and no chipping_TwoO_ThreeSystem multiple layers thick
Excellent cutting performance over a long period of time
We obtained the research result that it exerts itself. [0005] The present invention has been made based on the above research results.
It has been made, and Ti charcoal
One or more of a nitrided / oxide layer and Al_TwoO_ThreeComposed of layers
Hard coating layer with an average layer thickness of 7 to 20 μm
In the coated carbide cutting tool comprising_TwoO_Threelayer
Has an average layer thickness of 0.5 to 3 μm, and 0.01 to
S-containing Al containing 0.2 atomic% of S component_TwoO_Threeunit
At least one of the layers and an average layer thickness of 0.2 to 2 μm
Containing Ti containing 0.3 to 2 atomic% of Ti
l_TwoO_ThreeA comprising at least two alternate layers of unit layers
l_TwoO_ThreeA multi-layer system, and the Al_TwoO_ThreeSystem multiplex
Coated carbide cutting with an average layer thickness of 1 to 10 μm
The tool has features. Next, the coated carbide cutting tool according to the present invention will be described.
Then, the reason why the numerical value is limited as described above will be described. (A) Average thickness of hard coating layer If the average layer thickness is less than 7 μm, the desired wear resistance is secured.
On the other hand, the average layer thickness of which exceeds 20 μm
The chipping and chipping of the cutting edge
Have an average layer thickness of 7 to 20 μm, preferably 10 to 1 μm.
It was determined to be 8 μm. (B) S-containing Al_TwoO_ThreeAverage layer of unit layer
Thick If the average layer thickness is less than 0.5 μm,
High speed and thick film cannot be fully utilized.
If the average layer thickness exceeds 3 μm, Al_TwoO _ThreeSystem multiplex
Since the embrittlement tendency appears in the layer, its average
The layer thickness is defined as 0.5 to 3 μm, preferably 1 to 2.5 μm.
I did. (C) S-containing Al_TwoO_ThreeS content in unit layer
amount If the content is less than 0.01 atomic%, the film formation can be speeded up and
And the desired effect cannot be obtained for thickening,
If it exceeds 0.2 atomic%, the material itself becomes remarkably embrittled.
Therefore, the content is preferably 0.01 to 0.2 atomic%,
Or 0.05 to 0.15 atomic%. (D) Ti-containing Al_TwoO_ThreeAverage of unit layer
Layer thickness If the average layer thickness is less than 0.2 μm, Al_TwoO_ThreeSystem multilayer
The desired toughness cannot be ensured, while the average layer
If the thickness exceeds 2 μm, the abrasion resistance will decrease sharply.
Therefore, the average layer thickness is preferably 0.2 to 2 μm.
Or 0.5 to 1.5 μm. (E) Ti-containing Al_Two O_Three Ti of unit layer
Content If the content is less than 0.3 atomic%, Al_Two O_Three System multiplex
The desired toughness of the layer cannot be ensured,
If the amount exceeds 2 atomic%, the wear resistance will decrease.
Therefore, the content is preferably 0.3 to 2 atomic%,
Is determined to be 0.4 to 1 atomic%. (F) Al_TwoO_ThreeAverage layer thickness of multiple layers If the average layer thickness is less than 1 μm, excellent heat-resistant plastic deformation
The hard coating layer can be made
On the other hand, if the average layer thickness exceeds 10 μm,
Since chipping and chipping are likely to occur, the average
The layer thickness was determined to be 1 to 10 μm, preferably 3 to 7 μm. [0012] DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, coated carbide cutting of the present invention
The tool will be specifically described with reference to examples. As raw material powder
WC powder having an average particle diameter of 3 μm and (T
i, W) C [TiC / WC = 30/70 by weight ratio] powder
And (Ti, W) CN [TiC / TiN]
/ WC = 24/20/56) powder, 1.3 μm Ta
C powder and 1.2 μm Co powder
The raw material powder was blended into the blending composition shown in Table 1 and
And wet-mixed for 72 hours, dried and then 1ton / cm ^Twoof
Press molding into a green compact with pressure
^-2Sinter under the condition of torr kept in vacuum for 1 hour in vacuum.
Indexable insert type of O standard CNMG120408
Carbide substrates A to D each having a shape were produced. About
Then, the surface of each of the above-mentioned super hard substrates A to D is formed into a normal
Tables 3 and 4 were obtained using a chemical vapor deposition apparatus under the conditions shown in Table 2.
The hard coating layer having the composition and average layer thickness shown
Al_TwoO_ThreeTable 3 shows the multiple layers_TwoO_ThreeIndicated by multiple
To form the coated carbide cutting tool 1 of the present invention.
8 and conventional coated carbide cutting tools 1-8
Was. [0013] Next, various coated carbides obtained as a result are obtained.
About cutting tools, Work material: SCM440 (Hardness: H_B230) Length direction
Round bar with 4 equally spaced vertical grooves, Cutting speed: 220m / min., Feed: 0.4mm / rev., Cut: 1.5mm, Cutting time: 10 minutes, High feed intermittent cutting test of steel under the conditions of Work material: SCM439 (Hardness: H_B270) square timber, Cutting speed: 160m / min., Feed: 0.3mm / rev., Cut: 3mm, Cutting time: 10 minutes, Intermittent cutting test of steel dry high depth of cut under the conditions of
In each test, the flank wear width of the cutting blade was measured. this
Table 5 shows the measurement results. [0014] [Table 1] [0015] [Table 2][0016] [Table 3] [0017] [Table 4][0018] [Table 5] [0019] From the results shown in Table 5, it can be seen that the coating of the present invention
The hard cutting tools 1 to 8 are made of a hard coating layer of Al
_TwoO_ThreeSystem multilayer is excellent despite its thick film
With high toughness, high feed cutting and high cutting
Chipping or chipping of the cutting edge even when performing incision cutting
No wear and excellent wear resistance
Hard cutting tools 1 to 8 are made of thick-film S-containing Al_TwoO_ThreeDue to layer
In a relatively short time, chipping or chipping of the cutting edge occurs,
It is clear that the service life is reached. As mentioned above,
The coated cemented carbide cutting tool according to the invention comprises a hard coating
Layer Al_TwoO_ThreeThe system multilayer can be made thick, and
Al of this thick film_TwoO_ThreeSystem multilayer has excellent toughness
Therefore, the hard coating layer is excellent even in severe cutting conditions.
And excellent cutting performance over a long period of time.
Therefore, cutting efficiency can be improved and
And satisfactorily respond to labor and labor savings.
You.

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor ▲ Isao ▼ Hitoshi Tomi 1511 Furamagi, Ishishita-cho, Yuki-gun, Ibaraki Pref. Mitsubishi Materials Corporation Tsukuba Works (56) References JP-A-9-150301 (JP, A) JP-A-9-174305 (JP, A) JP-A-7-299608 (JP, A) JP-A-54-10314 (JP, A) JP-A-59-1984 162270 (JP, A) JP-A-57-137460 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23B 27/14 C23C 16/30

Claims (1)

(57) [Claim 1] A Ti carbide layer, a nitride layer, a carbonitride layer, a carbonate layer, a carbonitride layer, and a carbonaceous layer on a surface of a tungsten carbide-based cemented carbide substrate. A hard coating layer composed of at least one of the nitrided oxide layers and an aluminum oxide layer,
In a cutting tool made of a surface-coated tungsten carbide-based cemented carbide formed with an average layer thickness of 7 to 20 μm, the aluminum oxide layer constituting the hard coating layer is added to the cutting tool.
At least one S-containing aluminum oxide unit layer having an average layer thickness of 5 to 3 μm and containing 0.01 to 0.2 atomic% of sulfur (S), and an average layer thickness of 0.2 to 2 μm And an aluminum oxide-based multilayer composed of at least two alternating layers of Ti-containing aluminum oxide unit layers containing 0.3 to 2 atomic% of Ti, and an average layer of the aluminum oxide-based multilayer A cutting tool made of a surface-coated tungsten carbide-based cemented carbide having a hard coating layer with excellent fracture resistance, characterized in that the thickness is 1 to 10 μm.