JPS5819737B2 - High hardness sintered body for tools and its manufacturing method - Google Patents

Description

【発明の詳細な説明】 立方晶型窒化硼化（Ｃｕｂｉｃ ＢＮ以下ＣＢＮと略す
）はダイヤモンドに次ぐ高硬度の物質であり、超高圧高
温下で合成される。DETAILED DESCRIPTION OF THE INVENTION Cubic boron nitride (Cubic BN, hereinafter abbreviated as CBN) is a material with a hardness second only to diamond, and is synthesized under ultra-high pressure and high temperature.

現在既に研削用砥粒として防用されており、また切削用
途にはＣＢＮを金属Ｃｏなどで結合した焼結体が一部に
防用されている。Currently, it is already being used as abrasive grains for grinding, and some sintered bodies made of CBN bonded with metal Co or the like are also used for cutting purposes.

このＣＢＮを金属で結合した焼結体は切削工具として防
用した場合、結合金属相の高温での軟化による耐摩耗性
の低下や、被剛材金属が溶着し易すい為に工具が損傷す
るといった欠点がある。When this sintered body of CBN bonded with metal is used as a cutting tool, the wear resistance decreases due to the softening of the bonded metal phase at high temperatures, and the tool is damaged because the rigid material metal tends to weld. There are drawbacks such as:

本発明は、このような金属で結合した焼結体でなくミ高
強度で耐熱性に優れた硬質化合物を結合相とした工具用
途に適した新らしいＣＢＮ焼結体に関するものである。The present invention relates to a new CBN sintered body that is suitable for tool use and uses a hard compound having high strength and excellent heat resistance as a binder phase instead of such a sintered body bonded with metal.

ＣＢＮｉ高Ｎｉであるとともに高温下においても金属と
友応し難く、また高い熱伝導率を有する物質である。CBNi is a material that is high in Ni, difficult to interact with metals even at high temperatures, and has high thermal conductivity.

これ等の特性は切削工具等の工具材の基本的な要求特性
でもある。These characteristics are also the basic required characteristics of tool materials such as cutting tools.

このようなＣＢＨの特徴を年かした焼結体を得る為には
、例えばＣＢＮ粉采のみを焼結することが考えられる。In order to obtain a sintered body that takes advantage of the characteristics of CBH, it is conceivable to sinter only CBN powder, for example.

しかしＣＢＮのみからなる焼結体を得る為には極めて高
い圧力と温度が必要であり、ダイヤモンド合成に用いら
れるような超高圧、高温装置を用いても装置の耐用回数
が制限され、現状では工業的な生産は困難である。However, in order to obtain a sintered body made only of CBN, extremely high pressure and temperature are required. production is difficult.

発明者等はＣＢＮに済当な結合材とな名物質を加えて工
業的に生産可能であり、且つＣＢＮの有する優れた特徴
をできる限り生かした焼結体を得ることを考え本発明に
到達した。The inventors arrived at the present invention by adding a suitable binder and well-known substance to CBN to obtain a sintered body that can be produced industrially and that makes the most of the excellent characteristics of CBN. did.

本発明あ焼結体ではＣＢＮに窒化アルミニウム（以下Ａ
′ｔＮと記す）を結合材として加える。In the sintered body of the present invention, aluminum nitride (hereinafter referred to as A) is added to CBN.
'tN) is added as a binder.

Ａ４Ｎはその純粋なものばＢｅＯに匹適する高い熱伝導
率添布し、また鉄属金属等の金属に対して高温でも反応
しない耐熱化合物である。A4N has a high thermal conductivity comparable to that of BeO in its pure form, and is a heat-resistant compound that does not react with metals such as ferrous metals even at high temperatures.

しかし比較的に高温下での蒸気圧が高く、その純粋なも
のは通常のホットプレスでは緻密な焼結体が得られ難く
、また硬度もマイクロビッカース硬度で約Ｌ２００程度
であり、アルミナやＷＣ，’ＴｉＣ等の工具材に用いら
れる他の化合物に比較すると低く、それ自体では工具用
途に適さない。However, its vapor pressure is relatively high at high temperatures, and it is difficult to obtain a dense sintered body using normal hot pressing when it is pure.Also, its hardness is approximately L200 in terms of micro Vickers hardness, and it is difficult to obtain a dense sintered body using a pure material such as alumina, WC, etc. 'It is low in comparison with other compounds used in tool materials such as TiC, and is not suitable for tool use by itself.

発明者等はＣＢＨに各種の化合物を加えた焼結体を試作
したが、ＡｔＮを加えた場合は小量の添加でもＣＢＮの
焼結性が著しく改善され、ＣＢＮの含有量が８０％以上
の緻密な焼結体が容易に得られることを見出した。The inventors prototyped sintered bodies by adding various compounds to CBH, and when AtN was added, the sinterability of CBN was significantly improved even with a small amount of addition, and the CBN content was 80% or more. It has been found that a dense sintered body can be easily obtained.

第１図はＣＢＮの含有量が異なる焼結体についてその硬
度を測定した結果である。FIG. 1 shows the results of measuring the hardness of sintered bodies with different CBN contents.

ＣＢＮは平均粒度３μのものを使用し、酸素含有量が重
量で０．９％のＡＡＮ粉末を混合して超高圧下で焼結し
て試料を作成したものである。CBN with an average particle size of 3 μm was used, and the sample was prepared by mixing AAN powder with an oxygen content of 0.9% by weight and sintering it under ultra-high pressure.

ＣＢＮ含有量が体積で８０％を越えると焼結体の硬度は
顕著に高くなる。When the CBN content exceeds 80% by volume, the hardness of the sintered body increases significantly.

ＣＢＨの含有量が体積で７０％以下のものは硬度２２０
０程度である。If the CBH content is 70% or less by volume, the hardness is 220.
It is about 0.

ＡＡＮの添加によってＣＢＮ含有量が犬である緻密で高
硬度の焼結体が得られる理由は次の如く考えられる。The reason why a dense and highly hard sintered body with a high CBN content can be obtained by adding AAN is considered as follows.

ＡＡＮはＣＢＮに対して高温高圧下では変形し易すく、
焼結時にＣＢＮ粒間の空隙に塑性流動により浸入して緻
密化の役割を果す。AAN is more easily deformed than CBN under high temperature and high pressure.
During sintering, it penetrates into the voids between CBN grains due to plastic flow and plays the role of densification.

しかしこの作用ばＣＢＮより相対的に高温高圧下で変形
し易い他の物質についても言えることである。However, this effect also applies to other materials that are more easily deformed at high temperatures and pressures than CBN.

ＡｔＮの特徴的な作用はこの他にあるものと考えられる
。It is thought that there are other characteristic effects of AtN.

先ずＡＡＮは大方晶型窒化硼素をＣＢＮが安定な高温、
高圧下でＣＢＮに変換せしめる触媒作用を有すことが知
られている。First, AAN is made of mostly cubic boron nitride at a high temperature where CBN is stable.
It is known to have a catalytic action that converts it into CBN under high pressure.

ＣＢＮの含有量が犬である粉末を焼結する際には高温、
高圧下における焼結時にはＣＢＮ粒子が相互に接触する
状態まで緻密化されたとしても粒子一つ一つを見ると静
水圧的な応力下におかれているわけではなく、接触点以
外の部分の圧力は低いものと思われる。High temperature when sintering powder whose CBN content is high;
Even if the CBN particles are densified to the point where they are in contact with each other during sintering under high pressure, if you look at each particle individually, they are not under hydrostatic stress, and the parts other than the contact points are The pressure seems to be low.

このように焼結時においてばＣＢＮ粒子の全体が等しい
圧力、温度下にあるわけではなく、その一部は大方晶型
窒化硼素へ逆変態することが考えられる。As described above, during sintering, not all of the CBN particles are under the same pressure and temperature, and it is thought that a part of them undergoes reverse transformation into largely cubic boron nitride.

例えば米国特許第３，２３３，９８８号においてはＣＢ
Ｎ粒子のみを超高圧下で焼結した場合、六方晶型窒化硼
素が焼結体中に残留していることが示されている。For example, in U.S. Patent No. 3,233,988, CB
It has been shown that when only N particles are sintered under ultra-high pressure, hexagonal boron nitride remains in the sintered body.

発明者等の実験によってもこのことは確認されており、
前記した第１図に示したＡＡＮの含有量の異なる焼結体
と同−ＣＢＮ粉末を開用してＡｔＮを添加せず超高圧下
焼結したものは大方晶型窒化硼素が焼結体中に生成して
いることが検出された。This has been confirmed by experiments conducted by the inventors.
The sintered bodies with different AAN contents shown in Fig. 1 and those sintered under ultra-high pressure using the same -CBN powder without adding AtN have mostly cubic boron nitride in the sintered bodies. was detected to be generated.

また本発明のＡＡＮを含むものには六方晶型窒化硼素は
検出されなかった。Furthermore, no hexagonal boron nitride was detected in the sample containing AAN of the present invention.

このことからＡ４Ｎは焼結時においてＣＢＮの逆変態を
防止する作用を有しているとみられる。From this, it appears that A4N has the effect of preventing reverse transformation of CBN during sintering.

更に発明者等ばＡＡＮを添加した焼結体について詳しく
調べた結果焼結体中の結合相として存在するＡ／ＬＮは
純粋なＡ、／、Ｎではなく、焼結時にＣＢＮと反応して
硼素Ｂを固溶した相であることを見出した。Furthermore, the inventors investigated in detail the sintered body containing AAN, and found that the A/LN present as a binder phase in the sintered body was not pure A, N, but reacted with CBN during sintering to form boron. It was found that the phase contained B as a solid solution.

調査の為原料粉末として粒径１００μ前後の粗粒ＡｔＮ
を用いてＣＢＨ粉と混合しこれを超高圧下で焼結した。Coarse AtN with a particle size of around 100μ was used as the raw material powder for the investigation.
was used to mix with CBH powder, and this was sintered under ultra-high pressure.

焼結体中の粗粒Ａ７Ｎ相についてオージェ電子分光分析
装置を用いて分析した結果ＡｔＮ相中にＢが存在するこ
とが確認された。As a result of analyzing the coarse A7N phase in the sintered body using an Auger electron spectrometer, it was confirmed that B was present in the AtN phase.

Ｘ線回折による調査ではＣＢＮとＡｔＮに相当する回折
線のみが検出され、焼結体中に存在するＡ４Ｎは結晶型
は純粋なＡｔＮと等しく、Ａ／、原子の一部をＢが置換
した構造のものと推定される。In the investigation by X-ray diffraction, only diffraction lines corresponding to CBN and AtN were detected, and the crystal type of A4N present in the sintered body is the same as pure AtN, and it has a structure in which A/ and some of the atoms are replaced by B. It is presumed to be from

またこの焼結体中におけるＡＡＮ相のマイクロビッカー
ス硬度を測定したところ、２，０００〜２，２００の値
を示した。Furthermore, when the micro-Vickers hardness of the AAN phase in this sintered body was measured, it showed a value of 2,000 to 2,200.

純粋なＡ／、Ｎのみの焼結体では硬度は１，２００程度
であり、この焼結体でばＡ７Ｎ相がＢを固溶することに
より硬度が上昇したものと考えられる。A pure sintered body containing only A/N has a hardness of about 1,200, and it is thought that the hardness of this sintered body is increased due to the solid solution of B in the A7N phase.

このことは第１図に示したＣＢＮ含有量を変えた場合の
焼結体の硬度変化からも裏付けられる。This is also supported by the change in hardness of the sintered body when the CBN content is changed, as shown in FIG.

即ち結合相の硬度に大きく依存すると考えられるＣＢＨ
の含量が体積で７０％以下の焼結体の硬度はほぼ２，２
００の一定値に近づいている。In other words, CBH is considered to be largely dependent on the hardness of the binder phase.
The hardness of a sintered body with a content of 70% or less by volume is approximately 2.2
It is approaching a constant value of 00.

このようにＣＢＮは添加したＡｔＮと焼結時に反応する
。In this way, CBN reacts with the added AtN during sintering.

このことによりまた焼結が促進されるものと考えられる
。It is believed that this also promotes sintering.

以上述べた如く本発明の焼結体ではＣＢＮの結合材とし
てＡＡＮを用いることにより、焼結性が著しく改善され
、ＣＢＮの有する工具材としての特性を生かした焼結体
が得られる。As described above, by using AAN as a binder for CBN in the sintered body of the present invention, the sinterability is significantly improved, and a sintered body that takes advantage of the properties of CBN as a tool material can be obtained.

更に焼結体の結合相であるＡ４Ｎ相はＢを固溶すること
によ虱硬度の高い化合物に転化し、高硬度の焼結体が得
られる。Furthermore, the A4N phase, which is the binder phase of the sintered body, is converted into a compound with high lice hardness by solid solution of B, and a sintered body with high hardness is obtained.

切削工具等の工具材として使用される本発明の焼結体は
ＣＢＮの含有量が体積で８０％以上９９％以下のもので
ある。The sintered body of the present invention used as a tool material such as a cutting tool has a CBN content of 80% or more and 99% or less by volume.

８０％未満では第１図に見られるように硬度が相対的に
低く、工具としての性能も他の工具材に比較して顕著に
優れているとは言えない。If it is less than 80%, the hardness is relatively low as shown in FIG. 1, and the performance as a tool cannot be said to be significantly superior compared to other tool materials.

また９９％を越えると焼結性が悪くなる。Moreover, if it exceeds 99%, sinterability will deteriorate.

また焼結体中のＣＢＨの粒度が１０μ以下のものが工具
としての性能が優れている。Further, a sintered body with a particle size of CBH of 10 μm or less has excellent performance as a tool.

１０μを越えるとＣＢＮの含有量が９０％を越える焼結
体では焼結性が悪い。If the CBN content exceeds 10μ, sinterability is poor in a sintered body with a CBN content of more than 90%.

また焼結体を切削工具として用いたときには被削材の面
粗度はＣＢＮ粒子の粒径が細いものほど良い結果が得ら
れる。When the sintered body is used as a cutting tool, the finer the CBN particle size, the better the surface roughness of the workpiece.

本発明の焼結体の製造に当って防用するＡ／ｌ、Ｎ原料
粉末は酸素含有量の少ないものを使用する必要がある。In producing the sintered body of the present invention, it is necessary to use powders with low oxygen content as the A/L and N raw material powders used for protection.

実験によるとＡ４Ｎ中の酸素含有量が３％を越えると焼
結性が阻害される。Experiments have shown that when the oxygen content in A4N exceeds 3%, sinterability is inhibited.

これは恐ら＜ＣＢＮとＡ、ｆｆＮの焼結時における反応
が抑制される為と考えられる。This is probably because the reaction between CBN, A, and ffN during sintering is suppressed.

また超高圧下で焼結する工程においてもできる限り粉末
が酸化することのないように脱気された密閉容器中にＣ
ＢＮとＡＡＮの混合粉末またはその型押体を封入して焼
結する必要がある。In addition, even in the process of sintering under ultra-high pressure, carbon dioxide is stored in a degassed closed container to prevent the powder from oxidizing as much as possible.
It is necessary to encapsulate and sinter a mixed powder of BN and AAN or a stamped body thereof.

超高圧下焼結に使用する装置はベルト型、ガードル型の
ダイヤモンド合成に用いられる超高圧装置である。The equipment used for ultra-high pressure sintering is a belt-type or girdle-type ultra-high pressure apparatus used for diamond synthesis.

焼結における圧力、温度条件は第２図図に示したＣＢＨ
の安定領域で行なう。The pressure and temperature conditions for sintering are as shown in Figure 2.
Perform this in the stable region of

ＡｔＮの添加量やＣＢＮ原料粉末の粒度等によっても異
なるが圧力は約４０ｋｂ以上、温度は約１，２００℃以
上で保持時間は５分以上で行なう方が好ましい。The pressure is preferably about 40 kb or more, the temperature is about 1,200° C. or more, and the holding time is 5 minutes or more, although it varies depending on the amount of AtN added and the particle size of the CBN raw material powder.

尚本発明の焼結体の結合相中にはＢを含むＡｔＮ以外の
もの、例えばＦｅ 、Ｃｏ 、Ｎｉ 、Ｃｕ 等の金
属やＷＣ，ＴｉＣ，ＴｉＮ等周期律表第４ａ、５ａ、６
ａ族金属の炭化物、窒化物、硼化物やＡ４０３，８１３
Ｎ４等の耐熱耐摩耗性の化合物を含むものであっても良
い。The binder phase of the sintered body of the present invention contains B-containing substances other than AtN, such as metals such as Fe, Co, Ni, and Cu, as well as metals such as WC, TiC, TiN, etc. of Periodic Table 4a, 5a, and 6.
Group A metal carbides, nitrides, borides and A403,813
It may also contain a heat-resistant and wear-resistant compound such as N4.

但しその量は本発明の焼結体の特性を大きく低下せしめ
ない範囲であり、結合相の体積割合でＡ７Ｎの量以下、
即ち５０％以下０．１％以上が好ましい。However, the amount is within a range that does not significantly reduce the properties of the sintered body of the present invention, and the volume percentage of the binder phase is less than or equal to A7N,
That is, it is preferably 50% or less and 0.1% or more.

以下実施例により更に具体的に説明する。This will be explained in more detail below with reference to Examples.

実施例 １ 平均粒度３μのＣＢＮ粉末と一３２５メツシュのＡ７Ｎ
粉末を第１表の組成に配合した。Example 1 CBN powder with average particle size of 3μ and A7N with 1325 mesh
The powders were formulated to the composition shown in Table 1.

尚Ａ／、Ｎ粉末の不純物酸素の含有量は０．９重量％で
ある。The content of impurity oxygen in the A/N powder is 0.9% by weight.

溶媒としてアセトンを使用してボールミル混合後、粉末
を２ｔ／ｉで型押成型し直径１０ｍｍ厚さ１．５ｍｍの
ペレットを作成した。After mixing in a ball mill using acetone as a solvent, the powder was pressed at 2t/i to form pellets with a diameter of 10 mm and a thickness of 1.5 mm.

この粉末をＴｉ製の容器に入れ、脱気後型子ビームによ
り溶接密閉した。This powder was placed in a container made of Ti, and after degassing, the container was welded and sealed using a mold beam.

この容器をガードル型超高圧装置内に装入した。This container was placed in a girdle type ultra-high pressure device.

圧力媒体としてはパイロフィライトを用い、加熱には黒
鉛ヒーターを使用した。Pyrophyllite was used as the pressure medium, and a graphite heater was used for heating.

先ず圧力を５５ｋｂに昇圧し、次いで温度を１５００℃
に十−けた。First, the pressure was increased to 55kb, and then the temperature was increased to 1500℃.
It was ten digits.

１０分間保持したのちに温度を下げ、降圧して試料を回
収した。After holding for 10 minutes, the temperature was lowered and the pressure was lowered to collect the sample.

得られた焼結体をダイヤモンド砥石で研削後ダイヤモン
ドペーストでラッピングし、ビッカース硬度を測定した
。The obtained sintered body was ground with a diamond grindstone and then wrapped with diamond paste, and its Vickers hardness was measured.

測定荷重は１０ｋｇである。The measured load was 10 kg.

結果は第１表及び第１図に示した。本発明の焼結体Ｆを
使用して切削加工用のバイトを作成した。The results are shown in Table 1 and Figure 1. A cutting tool for cutting was created using the sintered body F of the present invention.

圧延ロールに用いられるショアー硬度８０のチルド鋳鉄
をこのバイトを用いて切削速度１ｏ ｏ ｍ／ｆ’ｒ、
切込み１ｍｍ、送り０．５ｍｍ／回転で切削した。Chilled cast iron with a shore hardness of 80 used for rolling rolls can be cut using this cutting tool at a cutting speed of 1 o m/f'r,
Cutting was performed with a depth of cut of 1 mm and a feed rate of 0.5 mm/rotation.

比較の為に市販のＣｏを主体とする金属を結合材とする
ＣＢＮ焼結体で作成したバイトを用いて同一条件でテス
トした。For comparison, a test was conducted under the same conditions using a commercially available cutting tool made of a CBN sintered body whose binder was a metal mainly composed of Co.

本発明の焼結体Ｆを用いたものは２０分間切削してバイ
トの逃げ面摩耗中が０．２籠であった。In the case of using the sintered body F of the present invention, the flank wear of the cutting tool was 0.2 cages after cutting for 20 minutes.

比較した市販のＣＢＮ焼結体は１０分で同一摩耗に達し
た。The commercially available CBN sintered body compared reached the same wear in 10 minutes.

実施例 ２ 第２表の組成に各粉末を配合した。Example 2 Each powder was blended into the composition shown in Table 2.

防用したＣＢＮ原料粉末及びＡｔＮ粉末は実施例１と同
一のものである。The CBN raw material powder and AtN powder used were the same as in Example 1.

実施例１と同様にして圧力５５ｋｂ、温度１４００℃に
２０分間保持して焼結体を得た。A sintered body was obtained in the same manner as in Example 1 by maintaining the pressure at 55 kb and the temperature at 1400° C. for 20 minutes.

各々の焼結体について荷重１０ｋｇで測定したビッカー
ス硬度を第２表に示した。Table 2 shows the Vickers hardness of each sintered body measured under a load of 10 kg.

実施例 ３ 平均粒度１μのＣＢＮ粉末と酸素含有量１．９％の一３
２５メツシュＡ４Ｎ粉末を体積％で９５％。Example 3 CBN powder with an average particle size of 1μ and oxygen content of 1.9%
25 mesh A4N powder at 95% by volume.

５％の割合に配合し、湿式ボールミル混合した〇この混
合粉末を２ｔ／ｉの圧力で型押成型し、直径１０龍、厚
さ］、、５ｍｍのベレットを作成した。This mixed powder was mixed in a wet ball mill at a ratio of 5% and was pressed and molded at a pressure of 2 t/i to form a pellet with a diameter of 10 mm and a thickness of 5 mm.

実施例１と同様のＴｉ製容器に予じめ焼結された直径１
０１ｎｒ／Ｌ１厚さ３ｍｍのＷＣ−７％Ｃｏ超硬合金円
板を入れ、これに接して直径１０ｍｇ、厚さ５０μのＴ
ａ板を置き、その上ζこ前記型押体を重ねて置いた。Diameter 1 pre-sintered into a Ti container similar to Example 1
01nr/L1 A WC-7%Co cemented carbide disk with a thickness of 3mm is inserted, and a T with a diameter of 10mg and a thickness of 50μ is placed in contact with it.
A plate was placed, and the embossed body was placed on top of it.

容器を脱気後密閉し、実施例１と同様にして圧力５５ｋ
ｂ、温度１５００℃で１０分間保持して焼結した。After degassing the container, seal it and apply the pressure to 55k in the same manner as in Example 1.
b. Sintering was carried out by holding at a temperature of 1500°C for 10 minutes.

回収された焼結体は厚さ約１ ｍｍのＣＢＮ焼結体の層
がＷＣ−７％Ｃｏ超硬合金の円板ζこ強固に接合されて
いた。In the recovered sintered body, a layer of CBN sintered body with a thickness of approximately 1 mm was firmly joined to a disk ζ of WC-7% Co cemented carbide.

これを切断して断面を観察したところ、ＣＢＮ焼結体層
と超硬合金の接合界面はＴａＣの厚さ約５０μの層が介
在していた。When this was cut and the cross section was observed, it was found that a TaC layer with a thickness of about 50 μm was interposed at the bonding interface between the CBN sintered body layer and the cemented carbide.

ＣＢＮ焼結体部を研摩してビッカース硬度を測定したと
ころ、硬度は４，２００であった。When the CBN sintered body was polished and its Vickers hardness was measured, the hardness was 4,200.

【図面の簡単な説明】[Brief explanation of drawings]

第１図はＡＡＮを結合材とするＣＢＮ焼結体についてＣ
ＢＨの含有量と硬度の関係を示したものである。 第２図は本発明の焼結体の製造条件を説明する為のもの
でＣＢＨの圧力、温度相図上の安定存在領域を示す。 第２図中人は立方晶窒化硼素安定域、Ｂは六方晶窒化硼
素安定域である。Figure 1 shows the CBN sintered body using AAN as the binder.
It shows the relationship between BH content and hardness. FIG. 2 is for explaining the manufacturing conditions of the sintered body of the present invention, and shows the stable existence region on the pressure and temperature phase diagram of CBH. In Fig. 2, the center indicates the cubic boron nitride stability region, and B indicates the hexagonal boron nitride stability region.

Claims (1)

【特許請求の範囲】 １ 粒度１０μ以下の立方晶型窒化硼素を容積で８０％
以上９９％以下含有し、残部が硼素を固溶した窒化アル
ミニウムまたは更に体積割合で該窒化アルミニウムの５
０％、以下０．１％以上のＦｅ。 Ｃｏ、Ｎｉ、Ｃｕの金属や周期律表４ａ、５ａ、６ａ族
金属の炭化物、窒化物、硼化物やＡ４！０３．Ｓｉ３Ｎ
４の耐熱性化合物を含む結合相からなる工具用高硬度焼
結体。 ２ 粒度１０μ以下の立方晶型窒化硼素粉末と酸素含有
量が重量で３％以下の窒化アルミニウム粉末、または該
窒化アルミニウムの体積量５０％以下０．１％以上のＦ
ｅ ｓ Ｎ ｉｓ Ｃｏ ｓ Ｃｕの金属や周期律表
４ａ、５ａ、６ａ族金属の炭化物、窒化物、硼化物、Ａ
４０３，８１３Ｎ４から選ばれた耐熱性化合物粉末を混
合し、これを粉状でもしくは型押成型後、容器内に密閉
し、この容器を超高圧装置に装入し、立方晶型窒化硼素
が安定な、圧力４０ｋｂ以上、温度１２００℃以上の超
高圧、高温下において立方晶型窒化硼素と窒化アルミニ
ウムを反応せしめると同時に焼結することを特徴とする
立方晶型窒化硼素を容積で８０％以上９９％以下で残部
が硼素を固溶した窒化アルミニウムまたは窒化アルミニ
ウムを主体とし、この窒化アルミニウムに上記割合の上
記金属寸たは上記化合物を含む結合相からなる工具用高
硬度焼結体の製造方法。[Claims] 1. 80% by volume of cubic boron nitride with a particle size of 10μ or less
Aluminum nitride containing 99% or more and the remainder containing boron as a solid solution, or further 5% by volume of the aluminum nitride.
0%, below 0.1% or more Fe. Metals such as Co, Ni, and Cu, carbides, nitrides, borides, and A4!03. Si3N
A high-hardness sintered body for tools consisting of a binder phase containing a heat-resistant compound of No. 4. 2. Cubic boron nitride powder with a grain size of 10μ or less and aluminum nitride powder with an oxygen content of 3% or less by weight, or F with a volumetric content of 50% or less and 0.1% or more of the aluminum nitride.
e s Nis Co s Cu metals, carbides, nitrides, borides of metals from groups 4a, 5a, and 6a of the periodic table, A
A heat-resistant compound powder selected from 403, 813N4 is mixed, this is powdered or after molding, it is sealed in a container, and this container is charged into an ultra-high pressure device, and the cubic boron nitride is stabilized. The cubic boron nitride is reacted with aluminum nitride at an ultra-high pressure of 40 kb or more and a temperature of 1200°C or more and is sintered at the same time.99 A method for producing a high-hardness sintered body for tools, which is mainly composed of aluminum nitride or aluminum nitride in which boron is dissolved as a solid solution in an amount of % or less, and a binder phase containing the above-mentioned metal dimensions or the above-mentioned compound in the aluminum nitride in the above-mentioned proportion.