JPS5918458B2 - M↓2B↓Boride-based cermet material containing type 5 boride - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a sintered material whose basic composition is a powder obtained by mixing one or more boride powders selected from M2B5 type borides of W2B5 and MO2B5 and metal powder as a binder. It is a sintered body made by adding one or more metal diborides, metal borides, carbides, nitrides, oxides, and silicides to these basic compositions, and has high density, high strength, and hardness. It concerns a new material with excellent heat resistance.

Metal borides, particularly metal diborides, generally have a high melting point, high hardness, and a golden color, and are therefore expected to be useful for cutting tools, watch frames, and the like.

Therefore, as is well known, attempts have been made to sinter a powder that is a mixture of two or more types of diboride metal powder and metal powder and use it for cutting tool materials or watch frame materials ( Japanese Patent Publication No. 51-30213).

However, the sintered material obtained using the known mixed powder has a defect in that the bending strength is 70 to 85 Ky/mm2, which is 1 m2.

In particular, sintered bodies with as high a transverse rupture strength as possible are desired for use as cutting tools, wear-resistant tools, wear-resistant mechanical parts, and heat-resistant mechanical parts.

On the other hand, the present inventors have conducted research on boride-based cermets containing W2B52Mo2B5.
W2B5. It was found that a high-strength material can be obtained by using Mo2B5 as an additive, and based on this knowledge, the present invention was developed.

That is, the present invention deals with M of W2 B5, Mo2 B5
At least one type of boride selected from 2B5 type borides and N12Cot with a weight coefficient of 50 or more
The basic composition is a sintered material consisting of Fe, Mo, Cr, W, Ti, Cu binder, or a mixture thereof, and T
iB2, CrB21 TaB21 MnB2)
MoB22 NbB22VB% metal diboride, CrB,
TaB, NbB, metal monoboride of VB, TiC, VC,
TaC, Ta2C, NbC.

Mo2C, MoC, WC, W2C, ZrC carbide, T
iN.

TaNtTa2NtZrN)VN, NbNtMo2N nitride, Ta02TiO2TiO2, Ti2O3, Zr
Oxide of O2, Mo5t2 tZrst2, T181
The present invention provides a sintered material containing one or more additives selected from the following silicides.

The metal powder of the binder material used in the present invention is 0% based on the total weight.
．． It is appropriate to add it in a range of 1 to 50% by weight.

If this amount is less than 0.1 weight factor, sufficient mechanical strength cannot be obtained, and if it exceeds 50 weight factor, heat resistance will decrease.

The metal diboride as an additive component can be added in an amount of 1 to 95% by weight.

If the weight is less than 1%, the mechanical strength cannot be improved sufficiently, and if it exceeds 95%, the sinterability will deteriorate.

Further, when adding metal monoboride as an additive component, it is appropriate to add it in an amount of 0.1 to 40 weight percent based on the total weight of the sintered body.

If this amount is less than 0.1 factor, sufficient improvement in mechanical strength cannot be achieved, and if it exceeds 40 factors, sinterability deteriorates.

Further, the additive components carbide, nitride, oxide, and silicide can be added in any desired mixture, but the total amount of addition is 0.1 to 40 weight equivalents.

In order to manufacture the boride-based cermet of the present invention, a powder containing one or more types of M2B5 type borides and a predetermined amount of binder powder, or
Type B - After adding one or more additives selected from metal borides, carbides, nitrides, silicides, and oxides, mix well and fill a mold such as a graphite mold with this mixed powder. death,
50 Ky/crit or more in vacuum, argon, or a neutral or reducing atmosphere such as hydrogen gas, preferably 200 Ky/cI? 10 under pressure around L
A sintered body can be produced by heating at 00°C or higher (in most cases, the optimal temperature range is 1700 to 1800°C).

Furthermore, a sintered body can also be produced by molding these mixed powders in a mold and firing them under normal pressure in a neutral or reducing atmosphere.

In addition, M2B, a type boride and metal diboride, -metal boride, carbide, nitride, oxide silicide are mixed, and the sintered body is preformed and sintered, and the binder is fused. The desired sintered body can also be manufactured by a so-called infiltration method in which a liquid is infiltrated.

The sintered cermet material obtained in this way has a relative density of
It has excellent mechanical strength, hardness, and heat resistance, making it ideal as a material for cutting tools, heat engine parts, rocket materials, etc.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 To 94 parts by weight of W2B5 powder, 5 parts by weight of Mo2B5 powder and 1 part by weight of Co powder were added and mixed thoroughly.

Next, put this mixed powder into a graphite mold and place it in a vacuum for 20 minutes.
It was heated at 1800° C. for 30 minutes while pressurizing to 0 KP/7.

In this way, the relative density is 100% and the transverse rupture strength is 160 K.
W/in2 room temperature Vickers hardness 2200 K? /mm2
．． Vickers hardness at 1000℃: 900 Ky/mm”
A sintered body was obtained.

The composition, sintering conditions, and characteristics of the sintered body of the sample thus obtained are shown in the following table.

Claims (1)

[Claims] 1. Intended for use as cutting tools, wear-resistant tools, wear-resistant mechanical parts, heat-resistant mechanical parts, and M2 of W2B5 and Mo2B5.
At least one type of boride selected from B5 type borides, and Ni and C in a proportion of 0.1 to 50% by weight based on the total weight.
A boride-based cermet material with high strength and high hardness, which is made by sintering a mixed powder with one or more binders selected from O, Fe, Mo, Cr, W, Ti, and Cu. 2 For cutting tools, wear-resistant tools, wear-resistant mechanical parts, heat-resistant mechanical parts, and M2 of W2B5 and Mo2B5.
At least one type of boride selected from B5 type borides, and Ni, Co in a weight ratio of 0.1 to 50 relative to the total weight.
, Fe, Mo, Cr, W, Ti, and one or more metal powder binders selected from Cu, and metal diboride is added to the mixture in an amount of 1 to 95% by weight. carbide, nitride,
High-strength and high-hardness porcelain made by sintering a mixed powder containing one or more additives selected from silicides and oxides in the range of 0.1 to 40% by weight. Chemical cermet material.