JPS586969A - Surface clad sintered hard alloy member for cutting tool - Google Patents

Abstract

PURPOSE:To provide a surface-clad sintered hard alloy member for cutting tolls provided with high abration resistance of a relief surface and high abrasion resistance of a rake surface by laminating thin films of TiCO, TiCNO and thin films of Al2O3 alternately on the surfaces of a specific super hard alloy. CONSTITUTION:The hard phase of sintered hard alloy members is constituted of >=1 kind of carbides and nitrides of 4a, 5a, 6a group metals and the bound phase is constituted of >=1 kind of iron group metals mainly. Thin layers of 0.1-1mum consisting of >= kind of TiCO and TiCNO satisfying the compsn. formula: Ti(C1-x-yNxOy)z where (0<=x<=0.75, 0.05<=y<=0.5, x+y<=0.8, 0.8<=z<=1.0) and thin layers of Al2O3 layers of 0.1-1mum thicknesses are formed alternately in >=4 layers, whereby the hard cladding layers of 0.5-20 overall layer thicknesses are formed. Such clad sintered hard alloy member has abrasion resistance of both relief surface and rake surface and provides superior cutting performance over a long period of time.

Description

[Detailed Description of the Invention] This invention forms a hard coating layer having excellent flank wear resistance and rake face wear resistance on the surface of a cemented carbide member or a surface-coated cemented carbide member. The present invention relates to a surface-coated cemented carbide member for cutting tools.

Conventionally, in cutting tools, the hard phase is mainly composed of one or more carbides and nitrides of metals of groups 4a +' 5ar and 6a of the periodic table of elements, while the binder phase is mainly composed of iron group metals. One of the metals, or six, is 2.
Titanium carbide (hereinafter referred to as "Tie"), titanium nitride (hereinafter referred to as "TiN"), titanium carbonitride (hereinafter referred to as "Ti0N"), and titanium carbide (hereinafter referred to as "Tie"), titanium nitride (hereinafter referred to as "TiN"), and titanium carbide (hereinafter referred to as "TiN") are used on the surface of this cemented carbide member.
), titanium carbonate (hereinafter referred to as Ti0O), and titanium carbonitride oxide (hereinafter referred to as TiCN0).
It is well known that a surface-coated cemented carbide member is used, which is formed by coating a single layer or a multilayer of two or more types with a total layer thickness of 1 to 10 μm.

In recent years, aluminum oxide (hereinafter referred to as A120.
A surface-coated cemented carbide member whose wear resistance is further improved by being coated with a material (shown by .) has been put into practical use as a cutting tool.

However, the former surface-coated cemented carbide member coated with a T1 compound as a hard coating layer exhibits excellent flank wear resistance during cutting, but has poor rake face wear resistance. In surface-coated cemented carbide members in which the coating layer was composed of AbOs, the characteristics of M2C were excellent in rake face wear resistance, but inferior in flank wear resistance.

Therefore, from the above-mentioned viewpoints, the present inventors investigated both flank wear resistance and rake face wear resistance.

As a result of our research to obtain a cutting tool with excellent properties, we discovered that the top hard coating layer coated on the surface of the above-mentioned cemented carbide member or surface-coated cemented carbide member was coated with a thin layer of M2O3 and carbonated. It is composed of four or more alternately laminated layers of titanium and one or two types of titanium (hereinafter collectively referred to as TiCN0), and the TiCN0 has the composition formula: : Ti
(O□-8-yNXOy)2. (However, O≦X≦0.
75°0.05≦y≦0.5. X+Y≦0.8. '0.
8≦2≦1. O), and furthermore, if the individual layer thickness of each thin layer is 0.1 to 1 μm and the total layer thickness is 0.5 to 20 μm, the M2O3 thin layer and the TiCN0 thin layer will be separated during cutting. In addition to becoming involved at the same time,
We obtained the knowledge that the TiNO thin layer has strong adhesion with the M2O3 thin layer, so it exhibits excellent cutting performance in both flank wear resistance and rake face wear resistance. It was.

This invention has been made based on the above knowledge, and the reason for limiting the number of hard coating layers as described above will be explained.

(a) Composition formula In the composition formula of Ti (C1-x-yNxOy)z in terms of atomic ratio, x + y≦0.8 is set because if the value of X + y exceeds 0.8, carbon in the TiCNo thin layer The amount decreases and the hardness becomes Hv: 2300 kg/- or less,
The hardness of AA203 becomes lower at Hv: 2700. T
It is desirable that the iCN0 thin layer and the AJ-203 thin layer have approximately the same hardness, and the TIG
As the hardness of the N O thin layer decreases, the wear resistance of the entire hard coating decreases, so x −)−y≦0.
It was set as 8.

Further, the role of oxygen (◯) in the TiONO thin layer is to increase chemical stability and strengthen the bond between M2C and the thin layer. Therefore, the M2C thin layer deposited on the O-containing TiCN0 thin layer has significantly better adhesion, in combination with the formation of microuniform nuclei in the A1.20s thin layer. However, if the proportion of O is less than 0.05, the formation of nuclei of M2O3 deposited thereon will be non-uniform and strong bonding strength will not be obtained. On the other hand, when the proportion of O exceeds 0.5,
Since it is no longer possible to secure the excellent flank wear resistance of the TiCN0 thin layer, the ratio y of 0 is set to 0.05.
~0.5.

Furthermore, the reason why the proportion of nitrogen (N) was set to 0.75 or less is because
If the N ratio X exceeds 0.75, C deficiency or 0 deficiency will occur, making it impossible to maintain the hardness and strengthen the bond with the AQ203 thin layer.
It was set at 75.

The ratio 2 of T1 to the total amount of C, N, and N is 0.
Even if the ratio is less than 8 or exceeds 1.0, the excellent flank wear resistance of TiCN0 cannot be ensured, so the ratio 2 must be 0.8 to 1.0.

(b) Layer thickness ■ Layer thickness of thin layer Ti Individual layer thickness of CNO thin layer and M2O3 thin layer is 0
．． If the thickness is less than 1 μm, it is difficult to distinguish between the layers, while if either of the thin layers exceeds 1 μm, T, i O
It is impossible for the N O thin layer and the M2 O The thickness of the layer was determined to be 0.1 to 1 μm.

■ Total layer thickness If the total layer thickness is less than 1 μm, the desired cutting life cannot be secured, while if the total layer thickness exceeds 20 μm, not only will further property improvement effects not be achieved, but the hard coating layer It takes a long time to form, making it impractical.
The total layer thickness of the hard coating layer was determined to be 1 to 20 μm.

Note that in order for the Ti0NO thin layer and the TiO3 thin layer to simultaneously participate in cutting and to ensure the desired cutting life, four or more layers must be alternately laminated.

In addition, the thickness of the thin layer constituting the hard coating layer is 0.1 to 1 μm.
They may be mutually varied within a range of m, and in this case, if the layer thickness is gradually made thinner toward the inside, the cutting performance will be further improved.

Further, the hard coating layer in the surface-coated cemented carbide member of Invention 9 is prepared by first placing the cemented carbide member or the surface-coated cemented carbide member in a chemical vapor deposition apparatus heated to a temperature of 900 to 1200°C. Tict as a reaction gas, hydrocarbons, Co, N2. MCt3,11.1H21 oxidizing gas (CO2, etc.) is introduced to chemically vaporize TiC0 and/or TiNO by introducing a mixed gas such as N2 and N2. AA by introducing a mixed gas such as
Formation rate of chemical vapor deposition of 203: 0.005-0.05
.mu.m/min), and is formed by repeating these two steps alternately and continuously or intermittently until a predetermined layer thickness of 1 to 20 .mu.m is reached.

Next, the surface-coated cemented carbide member of the present invention will be specifically explained by comparing examples and comparative examples.

Example 1 1000 indexable chips of P30 grade were prepared as cemented carbide members, these chips were installed in a heat-resistant alloy reaction vessel, and the chips were heated in an Ar atmosphere at a temperature of 1.
After heating to 100°C, a mixed gas consisting of TiC44 + CotN21 and N2 was added at a flow rate of 40/! ,/tomo,
After introducing the pressure crab into the container for 30 minutes under the condition of 200 torr and subsequently removing the residual gas in the container with a vacuum pump, a mixed gas consisting of tact3+ CO2 and N2 was introduced into the container at a pressure of 200 torr at a flow rate of 3547 m1n.
rr condition for 30 minutes, these two steps are alternately repeated 5 times each, and finally, by cooling in an Ar atmosphere, a material having a composition formula of T1Co, 2No60o, z and each individual layer is formed. a TiCN0 thin layer with a thickness of 0.5 μm;
A hard coating layer (total layer thickness:
A surface-coated indexable chip of the present invention (hereinafter referred to as a coated chip of the present invention) having a diameter of 5 μm was produced.

The coated chip of the present invention obtained as a result and the coating layer have a layer thickness:
Regarding the conventional surface coated indexable tip (hereinafter referred to as conventional coated tip) consisting of a 5 μm 712o3 single layer,
Work material: J-work S-8N5-8NC hardness HB: 210),
Cutting speed: 150m/mm, depth of cut 11.5, feed:
0.45 g/rev, Chip shape: SNMN4
A cutting test was conducted under 32 conditions and the life time was measured.

As a result, the coated chip of the present invention exhibited a life time of 50 minutes, whereas the conventionally coated chip exhibited a very short life time of only 10 minutes.

Example 2 Throw-away tips of the types shown in Table 1 were prepared as cemented carbide members and surface-coated cemented carbide members, and a A coated chip of the present invention was manufactured by forming a hard coating layer having the structure and layer thickness shown in the table.

Next, regarding the resulting coated chips of the present invention, work material: JIS-Fe12 (hardness HB: 180), cutting speed:
250m/breaking, depth of cut: 2mm, feed: -0.55m
++! / rev, Chip shape: SNMN 432
When a cutting test was conducted under the following conditions and the life time was measured, each exhibited an extremely long life time as shown in Table 1, and exhibited excellent cutting performance.

As mentioned above, the surface-coated cemented carbide member of the present invention has a top surface layer made of TiNO, which has excellent flank wear resistance.
It is composed of alternating layers of thin layers and thin M2O3 layers with excellent rake face wear resistance, so during cutting,
Both of these groove layers are simultaneously involved in providing excellent cutting performance over a long period of time in both the characteristics of lhK'''67'', relief resistance, 0 wear resistance''''''104''), and 1-side wear resistance. It shows itself.

Claims (2)

[Claims] (1) The hard phase is mainly elements 4a and 5a of the periodic table. and a cemented carbide member composed of one or more of carbides and nitrides of group 6a metals, while the binder phase is mainly composed of one or more of iron group metals. , on its surface, the compositional formula: T1 (C knee
-yNxOy),! ,. (However, 0≦X≦0.75, 0.05≦y≦0.5
゜x-1-y≦0.8.0.8≦2≦1.0). Made of one or two of titanium carbonate and titanium carbonitride that satisfy the following, the thickness of the layer is 0.1 to 1 μm
A hard coating layer with a total thickness of 0.5 to 20 μm is formed by laminating four or more layers of aluminum oxide and thin layers of aluminum oxide with a thickness of 0.1 to 1 μm. Surface-coated cemented carbide parts for cutting tools. (2) The hard phase is mainly composed of one or more carbides and nitrides of metals in Groups 4a+5a, - and 6a of the Periodic Table of Elements, while the binder phase is mainly composed of one metal in the iron group. or titanium carbide, titanium nitride, titanium carbonitride,
In a surface-coated cemented carbide member coated with a single layer or a multilayer of two or more of titanium carbonate and titanium carbonitride oxide, the surface thereof further has a composition formula: T l (Ox ,,,x −y N x
Oy) Z + (However, 0≦X≦o, 75, o
, o 5≦y≦0.5゜x −1−y≦0.8 , 0.
8≦2≦1.0). A thin layer consisting of one or two of titanium carbonate and titanium carbonitride that satisfies the following, and a thin layer with a layer thickness of 0.1 to 1 μm and a layer of aluminum oxide with a layer thickness of 0.1 to 1 μm. Laminated with 4 or more layers alternating with thin layers, and the total layer thickness is 0.
．． A surface-coated cemented carbide member for a cutting tool formed with a hard coating layer of 5 to 20 μm.