JPS58209554A - Multiple coating material and its manufacture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a material coated with a hard substance, particularly a multi-coated material effective in wear resistance and chipping resistance, and a method for producing the same.

Conventionally, WCC cemented carbide TiC-based cermets and TiN abrasive cermets have been coated with hard substances to improve their wear resistance.

However, although it is called wear resistance, there are three types of wear: abrasive wear seen on the flank, wear caused by chemical reaction with the rigid material seen in some parts of the crater, and oxidative wear seen mainly as boundary wear. Materials with high hardness are effective for abrasive wear, materials with high chemical stability are effective for crater wear, and materials with high oxidation resistance and thermal conductivity F1 are effective for boundary wear. It is known that

For this reason, conventionally, instead of coating with a single layer of carbide, nitride, etc.,
A method in which each layer is coated with a hard material that has different properties.

(2) A method of coating a solid solution of two to three types of hard substances having different properties, such as carbonitride, has been used as a method of improving wear resistance.

However, in the case of ■ above, of course, for example,
Although the outer layer has good abrasion resistance at the flank part, phenomena such as deterioration in abrasion resistance at a part of the crater occur, so no improvement in abrasion resistance can be expected.

In addition, since it is coated with a considerable thickness of different materials with different coefficients of thermal expansion, it is unavoidable that it is susceptible to thermal fluctuations and is prone to breakage during cutting.

Furthermore, in the case of (2) above, there is a problem in that solid solutions of different types of sandy materials generally tend to enhance the disadvantages of the hard materials rather than promoting their respective characteristics.

Therefore, neither method (1) or (2) above could be said to be an effective improvement method.

The object of the present invention is to improve the above-mentioned drawbacks of the prior art and provide a new coring tool with excellent wear resistance and chipping resistance.

The present invention is characterized in that a coating layer made of TiN and 1"IB is formed on the surface of a WC early-setting hard alloy, a TiC-based cermet, or a "TIN-based cermet" with a single layer thickness of 1 μm or more, preferably 0.1 μm or more. Ti to a total thickness of less than 5 μm and 2 to 15 μm
It is characterized by being coated with at least 6 layers, preferably 20 layers, of N, Ti and B2 alternately.

The material according to the invention has a monolayer thickness of less than 1 μm, preferably less than 0.5 μm, so that T
It becomes possible to cover the drawbacks of iN, and ultimately the strain between the coating material layers is uniformly distributed, stress concentration is eliminated, and thermal shock resistance is improved. Furthermore, since TiB2 has high hardness and excellent thermal conductivity, it significantly improves not only flank wear resistance but also boundary wear resistance. However, T
iB2 has a high affinity with iron-based alloys, so when cutting steel or cast iron, it tends to cause crater wear when used alone, but in the present invention, it is coated with multiple thin layers. , this drawback can be avoided.

In addition, in the present invention, the order in which the coating layers are stacked is base material, T
I N, T+ B2, Ti N, Ti B2
, . . . , the base material, Ti 82 , T
IN, TI B2.

Any order of TiN may be used.

The manufacturing method according to the present invention, particularly the method for forming a coating layer, uses a gas containing Ti, H and N, by chemical vapor deposition method.
For example, by intermittently introducing a mixed gas of TiC+3, T2, and N2 and a gas containing Ti, H, and B, such as a mixed gas of T1Cl, H, and BCI, it is possible to easily and effectively form multiple coatings. is possible.

Furthermore, as is conventionally known, when chemical vapor deposition is used, the Ti NM film formation temperature is approximately 970°C, T
The iB2 film formation temperature is as low as 920°C.

Therefore, when switching from TiN coating to TiB2 coating, or conversely from TiB2 coating to TiN coating, it is necessary to change the coating temperature, and at this time, it is inevitable that abnormal growth of the coating particles will occur, and the properties of the coating will change. This causes deterioration.

However, the inventors of the present application found that when gas is mixed intermittently, the frequency of nucleation of precipitated particles from the gas phase increases, but the growth rate slows down.Based on this, the present invention was completed. . Therefore, in the present invention, it is desirable to mix the gas intermittently, and this provides the excellent effect of being able to obtain fine particles even if the temperature at which TiB2 is coated is chosen to be the same as that for FiN. .

In this case, it is of course possible to apply an electromagnetic field to activate the plasma state.

Further, in the present invention, the number of multiple coating layers is at least 8 or more, preferably 20 or more. If there are less than 8 layers, the effect of the multiple coating described above cannot be sufficiently exhibited. In addition, the thickness of each single layer is adjusted to uniformly distribute the strain between the coating material layers.
The thickness is preferably 1 μm or less, preferably 0.511 m or less. This is because if the thickness exceeds 1 μm, the fracture resistance deteriorates.

Example 1 WC-6%CO cemented carbide was coated with T+N, r; B2 coating 19 with each layer having a thickness of 0.1 μm and a total thickness of 6 μm. This chip is used as a sample.

At the same time, as a comparative material, T! N
The upper layer was coated with a TiB2 film having a total thickness of 6 μm, each having a thickness of 3 μm. This chip is designated as sample B. A cutting test was conducted on these two types of samples under the following cutting conditions: Work material: 80 M3 Cutting speed: 200 m/'min Feed: 0.3 mm/rev Depth of cut: 2 mm. While the comparative B chip reached the end of its life due to wear of the flank after 17 minutes, the A chip according to the present invention showed good cutting performance even after 55 minutes of cutting.

Example 2 WC-8%TiC-8%TaC-6%CO TiB2. TiN coating 0.0511m each layer 18
A coating of μm was coated. This chip is designated as sample C. At the same time, the same cemented carbide 4- was used as a comparison material with TiB in the lower layer.
Add 3μ of TiN to each soil layer.

A film having a thickness of 5 μm, 9 squares, and 18 μm was coated. Let this chip be the sample [].

Next, these two types of samples were subjected to the above intermittent cutting conditions.
' rev depth of cut 1.5+nn+ Work material 80M3 10mm wide (cutting j) was performed. D tip of comparison material was 40
The impact C' was lost, but the C of the present invention is 1 of 700 times!
I hit (did not result in b deficiency).

As described above, according to the present invention, T! N.

11 [Multiple coating of 32 thin films in alternation]
Su-tai)? I' is a coated cemented carbide that is highly wear-resistant and impact resistant.
What to do/J Furukawano L1
1! Osamu Ichinari Jinji

Claims (1)

[Claims] 1. ``vVC group if!
and 11B2, the middle layer has a thickness of 1 μm.
A multi-coated material having a thickness of 18 m or more and having an I9 of 12 to 11 μm, reduced to an intersecting Tj of 12 to 11 μm, and 8 to 1 or more multi-coated. 2. The multi-coated material according to item 1, characterized in that the Jv of the single layer is 5 μm or less. 3.1 The number of covered @ layers is 20 or more ↓. 1. The multi-coated N slope according to item 1 or item 21ji. 4. WC-based cemented carbide, 1'iC-based cermet. Next, the TiN-based lead was charged as a substrate and placed in a 4-unit furnace.
l' i , tl and N with 1[n・Ij gas and -[
1. A method for producing a multi-coated material, which comprises alternately and intermittently introducing a gas containing 1°H &;