JP2004516226A - Refractory hard alloy in powder form for electrode production - Google Patents

Refractory hard alloy in powder form for electrode production Download PDF

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JP2004516226A
JP2004516226A JP2002554621A JP2002554621A JP2004516226A JP 2004516226 A JP2004516226 A JP 2004516226A JP 2002554621 A JP2002554621 A JP 2002554621A JP 2002554621 A JP2002554621 A JP 2002554621A JP 2004516226 A JP2004516226 A JP 2004516226A
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hard alloy
refractory hard
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サバン ボワリ
マルコ ブルーイン
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    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer

Abstract

本発明は、０．１〜３０μｍの平均粒径を有し、かつそれぞれグレインの凝集物で形成されている粒子を含んでなる粉末形態の耐火硬質合金であって、各グレインが、式（Ｉ）：ＡｘＢｙＸｚ（式中、Ａは遷移金属であり、Ｂはジルコニウム、ハフニウム、バナジウム、ニオビウム、タンタル、クロム、モリブデン、マンガン、タングステン及びコバルトから成る群より選択される金属であり、Ｘはホウ素又は炭素であり、ｘは０．１〜３の範囲、ｙは０〜３の範囲、かつｚは１〜６の範囲である）の耐火硬質合金のナノ結晶を含むことを特徴とする粉末形態の耐火硬質合金に関する。本発明の粉末形態の耐火硬質合金は、熱溶着又は粉末冶金による電極の製造用に好適である。The present invention is a refractory hard alloy in powder form comprising particles having an average particle size of 0.1 to 30 μm and each formed of agglomerates of grains, each grain having the formula (I) ): A x B y X z (where A is a transition metal and B is a metal selected from the group consisting of zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, manganese, tungsten and cobalt.) , X is boron or carbon, x is in the range of 0.1 to 3, y is in the range of 0 to 3, and z is in the range of 1 to 6). Powdered refractory hard alloy. The powdered refractory hard alloy of the present invention is suitable for producing electrodes by heat welding or powder metallurgy.

Description

【０００１】
発明の分野
本発明は、金属電気分解用の電極の分野における改良に関する。さらに詳細には、本発明は、このような電極製造用の粉末形態の耐火硬質合金に関する。
【０００２】
背景技術
アルミニウムは、慣習的に約９５０℃までの温度で溶融氷晶石（Ｎａ２ＡｌＦ６）中に溶解しているアルミナの電気分解によってホール−エール還元セル内で製造される。ホール−エールセルは、典型的に耐火材料の絶縁ライニングを備えたスチールシェルを有し、順次電極の溶融成分と接触する既焼成炭素ブロック製ライニングを有する。炭素ライニングはカソード基材として働き、溶融アルミニウムプールはカソードとして働く。アノードは、消費性炭素電極であり、通常コークスか焼によって製造された既焼成炭素である。
【０００３】
ホール−エールセル内での電気分解の間に、炭素アノードが消費されて、ＣＯ及びＣＯ２のような温室効果ガスの発生をもたらす。アノードは、周期的に変えなければならず、材料の浸食がアノード−カソード距離を変え、電極抵抗による電圧を高める。カソード側では、炭素ブロックが浸食及び電解質浸透を受ける。グラファイト構造内でナトリウム挿入が起こり、カソード炭素ブロックの膨潤及び変形をもたらす。電極間の電圧の増加は、該プロセスのエネルギー効率に逆効果を及ぼす。
【０００４】
電極材料として、ＴｉＢ２のような耐火硬質合金について広範囲の研究が行われている。ＴｉＢ２及び他の耐火硬質合金は、実際にアルミニウムに不溶性で、低い電気抵抗を有し、かつアルミニウムによって濡れる。しかし、ＴｉＢ２及び他の同様の耐火硬質合金は高い融点を有し、かつ高度に共有結合性なので、これら材料の造形は難しい。
【０００５】
発明の開示
従って、本発明の目的は、上記欠点を克服し、かつ熱溶着又は粉末冶金による電極の製造に好適な粉末形態の耐火硬質合金を提供することである。
本発明の一局面により、０．１〜３０μｍの平均粒径を有し、かつそれぞれグレインの凝集物で形成されている粒子を含んでなる粉末形態の耐火硬質合金であって、各グレインが、次式：
ＡｘＢｙＸｚ （Ｉ）
（式中、Ａは遷移金属であり、Ｂはジルコニウム、ハフニウム、バナジウム、ニオビウム、タンタル、クロム、モリブデン、マンガン、タングステン及びコバルトから成る群より選択される金属であり、Ｘはホウ素又は炭素であり、ｘは０．１〜３の範囲、ｙは０〜３の範囲、かつｚは１〜６の範囲である）の耐火硬質合金のナノ結晶を含むことを特徴とする粉末形態の耐火硬質合金が提供される。
【０００６】
本明細書で使用する場合、用語“ナノ結晶”は、１００ナノメーター以下のサイズを有する結晶を表す。
本明細書で使用する場合、表現“熱溶着”は、粉末粒子をトーチランプ内に注入し、かつ基材上に噴霧する技法を指す。粒子は高速度を得、飛行経路中に部分的又は全体的に溶融する。基材表面上の液滴の凝固によって皮膜が造られる。このような技法の例としては、プラズマスプレー、アークスプレー及び高速オキシ−燃料が挙げられる。
【０００７】
本明細書で使用する場合、表現“粉末冶金”は、バルク粉末をコンパクション又は造形後焼結工程によって所望形状のプレフォームに変換する技法を指す。コンパクションは、例えば冷一軸圧縮、冷等圧圧縮又は熱等圧圧縮のように、粉末に圧力を加える技法を意味する。造形は、粉末充填又はスラリーキャスティングのような、外部圧力を加えないで行う技法を意味する。
【０００８】
本発明は、その別の局面では、上記したような粉末形態の耐火硬質合金の製造方法をも提供する。本発明の方法は、以下の工程：
ａ）遷移金属及び遷移金属含有化合物から成る群より選択される第１試薬を供給する工程；
ｂ）ホウ素、ホウ素含有化合物、炭素及び炭素含有化合物から成る群より選択される第２試薬を供給する工程；
ｃ）ジルコニウム、ジルコニウム含有化合物、ハフニウム、ハフニウム含有化合物、バナジウム、バナジウム含有化合物、ニオビウム、ニオビウム含有化合物、タンタル、タンタル含有化合物、クロム、クロム含有化合物、モリブデン、モリブデン含有化合物、マンガン、マンガン含有化合物、タングステン、タングステン含有化合物、コバルト及びコバルト含有化合物から成る群より選択される任意の第３試薬を供給する工程；及び
ｄ）前記第１、第２及び第３試薬を高エネルギーボールミル粉砕に供し、それらの間に固体反応と、０．１〜３０μｍの平均粒径を有し、各粒子が上で定義した式（Ｉ）の耐火硬質合金のナノ結晶を含んでなる各グレインの凝集物で形成されている粒子の形成とを引き起こす工程；
を含む。
【０００９】
本明細書で使用する場合、表現“高エネルギーボールミル粉砕”は、約４０時間内で、式（Ｉ）の耐火硬質合金のナノ結晶グレインを含んでなる前記粒子を形成できるボールミル粉砕プロセスを指す。
【００１０】
図面の説明
添付図面では、図１は、実施例１で得られた粉末形態の耐火硬質合金のＸ線回折を示す。
発明の実施の形態
式（Ｉ）の耐火硬質合金の典型例としては、ＴｉＢ１．８、ＴｉＢ２、ＴｉＢ２．２、ＴｉＣ、Ｔｉ０．５Ｚｒ０．１Ｂ２、Ｔｉ０．９Ｚｒ０．１Ｂ２、Ｔｉ０．５Ｈｆ０．５Ｂ２及びＺｒ０．８Ｖ０．２Ｂ２が挙げられる。ＴｉＢ２が好ましい。
上記第１試薬として使用しうる好適な遷移金属の例としては、チタン、クロム、ジルコニウム及びバナジウムが挙げられる。チタンが好ましい。ＴｉＨ２、ＴｉＡｌ３、ＴｉＢ及びＴｉＣｌ２のようなチタン含有化合物も使用できる。
上記第２試薬として使用しうる好適なホウ素含有化合物の例としては、ＡｌＢ２、ＡｌＢ１２、ＢＨ３、ＢＮ、ＶＢ、Ｈ２ＢＯ３及びＮａ２Ｂ４Ｏ７が挙げられる。ホウ素含有化合物又は炭素含有化合物のどちらかとして炭化四ホウ素（Ｂ４Ｃ）を使用することもできる。
上記第３試薬として使用しうる好適な化合物の例としては、ＨｆＢ２、ＶＢ２、ＮｂＢ２、ＴａＢ２、ＣｒＢ２、ＭｏＢ２、ＭｎＢ２、Ｍｏ２Ｂ５、Ｗ２Ｂ５、ＣｏＢ、ＺｒＣ、ＴａＣ、ＷＣ及びＨｆＣが挙げられる。
【００１１】
好ましい実施形態によれば、本発明の方法の工程（ｄ）は、８〜２５Ｈｚ、好ましくは約１７Ｈｚの振動数で操作する振動ボールミルで行う。１５０〜１５００ｒ．ｐ．ｍ．、好ましくは約１０００ｒ．ｐ．ｍ．の速度で操作する回転ボールミルで行うこともできる。
別の好ましい実施形態によれば、工程（ｄ）は、アルゴン若しくはヘリウムを含むガス雰囲気のような不活性ガス下、又は水素、アンモニア若しくは炭化水素を含むガス雰囲気のような反応性ガス雰囲気下で行い、ダングリングボンドを飽和させ、それによって耐火硬質合金の酸化を防止する。アルゴン、ヘリウム又は水素の雰囲気が好ましい。粒子を保護膜で被覆するか、又はＭｇ若しくはＣａのような犠牲元素を該試薬と混ぜることもできる。さらに、工程（ｄ）の間にＹ２Ｏ３のような焼結助剤を添加することができる。
【００１２】
チタン及びホウ素又は炭素が化学量論量で存在するＴｉＢ２又はＴｉＣの特定の場合、この２種の化合物を出発原料として使用することができる。従って、それらを直接高エネルギーボールミル粉砕に供して、０．１〜３０μｍの平均粒径を有し、各粒子が、それぞれＴｉＢ２又はＴｉＣのナノ結晶を含むグレインの凝集物で形成されている粒子の形成を引き起こすことができる。
上述した高エネルギーボールミル粉砕により、非化学量論又は化学量論組成のどちらかを有する粉末形態の耐火硬質合金を得ることができる。
【００１３】
本発明の粉末形態の耐火硬質合金は、熱溶着又は粉末冶金による電極の製造用に好適である。耐火硬質合金の特性のため、金属電気分解時の毒性及び温室効果ガスの排出が低減し、かつ電極の寿命が延び、ひいては維持コストが低減する。より狭くかつ一定の内部電極距離も可能であり、それによって電極の抵抗降下を減少させる。
【００１４】
以下、非限定的な例によって本発明を説明する。
実施例１
約１７Ｈｚの振動数で操作するＳＰＥＸ８０００（商標）振動ボールミルを用い、ボール対粉末質量比４．５：１で、硬化鋼るつぼ内３．４５ｇのチタンと１．５５ｇのホウ素をボールミル粉砕することによってＴｉＢ２粉末を製造した。制御されたアルゴン雰囲気下で操作して酸化を防止した。るつぼを閉じ、ゴム製Ｏリングで封印した。５時間の高エネルギーボールミル粉砕後、添付図面のＸ線回折パターンに示されるようにＴｉＢ２構造が形成された。ＴｉＢ２の構造は、空間群Ｐ６／ｍｍｍ（１９１）を有する六方晶系である。粒径は、１〜５μｍの間で変化し、Ｘ線回折で測定した結晶サイズは、約３０ｎｍだった。
【００１５】
実施例２
５時間に代えて２０時間ボールミル粉砕を行うこと以外、実施例１に記載の同一手順及び同一操作条件下でＴｉＢ２粉末を製造した。生成した粉末は、実施例１で得られたものと同様だった。しかし、結晶サイズは小さかった（約１６ｎｍ）。
実施例３
チタンとグラファイトを粉砕すること以外、実施例１に記載の同一手順及び同一操作条件下でＴｉＣ粉末を製造した。
実施例４
５時間に代えて２０時間ボールミル粉砕を行うこと以外、実施例１と同一操作条件下で二ホウ化チタンをボールミル粉砕することによってＴｉＢ２粉末を製造した。初期構造は維持されたが、結晶サイズは１５ｎｍに縮小した。
【００１６】
実施例５
ＴｉＢ１．８粉末は、３．６ｇのチタンと１．４ｇのホウ素を粉砕すること以外、実施例１に記載の同一手順に従い、同一操作条件下で製造した。
実施例６
ＴｉＢ１．８粉末は、３．４ｇのチタンと１．７ｇのホウ素を粉砕すること以外、実施例１に記載の同一手順に従い、同一操作条件下で製造した。
実施例７
Ｔｉ０．５Ｚｒ０．５Ｂ２粉末は、１．９ｇのチタンと、３．１ｇの二ホウ化ジルコニウムと、０．８ｇのホウ素を粉砕すること以外、実施例１に記載の同一手順に従い、同一操作条件下で製造した。
【００１７】
実施例８
Ｔｉ０．９Ｚｒ０．１Ｂ２粉末は、２．９ｇのチタンと、０．６ｇのジルコニウムと、１．５ｇのホウ素を粉砕すること以外、実施例１に記載の同一手順に従い、同一操作条件下で製造した。
実施例９
Ｔｉ０．５Ｈｆ０．５Ｂ２粉末は、０．９ｇのチタンと、３．３ｇのハフニウムと、０．８ｇのホウ素を粉砕すること以外、実施例１に記載の同一手順に従い、同一操作条件下で製造した。
実施例１０
Ｚｒ０．８Ｖ０．２Ｂ２粉末は、３．５ｇのジルコニウムと、０．５ｇのバナジウムと、１．０ｇのホウ素を粉砕すること以外、実施例１に記載の同一手順に従い、同一操作条件下で製造した。
【図面の簡単な説明】
【図１】実施例１で得られた粉末形態の耐火硬質合金のＸ線回折を示す。[0001]
FIELD OF THE INVENTION The present invention relates to improvements in the field of electrodes for metal electrolysis. More particularly, the invention relates to a powdered refractory hard alloy for the production of such electrodes.
[0002]
BACKGROUND ART Aluminum is conventionally produced in a Whole-Ale reduction cell by electrolysis of alumina dissolved in molten cryolite (Na 2 AlF 6 ) at temperatures up to about 950 ° C. . Whole-Ale cells typically have a steel shell with an insulating lining of a refractory material, and have a lining made of calcined carbon block that is in sequential contact with the molten components of the electrodes. The carbon lining acts as the cathode substrate, and the molten aluminum pool acts as the cathode. The anode is a consumable carbon electrode, usually calcined carbon produced by coke calcination.
[0003]
Hall - during the electrolysis in the Eruseru, is consumed carbon anodes results in the generation of greenhouse gases such as CO and CO 2. The anode must be changed periodically; material erosion changes the anode-cathode distance and increases the voltage due to electrode resistance. On the cathode side, the carbon block undergoes erosion and electrolyte penetration. Sodium insertion occurs within the graphite structure, resulting in swelling and deformation of the cathode carbon block. Increasing the voltage between the electrodes has a negative effect on the energy efficiency of the process.
[0004]
As the electrode material, extensive studies have been conducted on refractory hard metal such as TiB 2. TiB 2 and other refractory hard metal actually insoluble in aluminum, have a low electrical resistance, and wet by aluminum. However, shaping TiB 2 and other similar refractory hard alloys is difficult because of their high melting points and the high degree of covalent bonding.
[0005]
DISCLOSURE OF THE INVENTION Accordingly, it is an object of the present invention to overcome the above disadvantages and to provide a refractory hard alloy in powder form suitable for the production of electrodes by thermal welding or powder metallurgy.
According to one aspect of the present invention, a powdered refractory hard alloy having an average particle size of 0.1 to 30 μm, and comprising particles each formed of agglomerates of grains, wherein each grain is: The following formula:
A x B y X z (I )
Wherein A is a transition metal, B is a metal selected from the group consisting of zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, manganese, tungsten and cobalt, and X is boron or carbon. X is in the range of 0.1 to 3, y is in the range of 0 to 3 and z is in the range of 1 to 6). Is provided.
[0006]
As used herein, the term "nanocrystal" refers to a crystal having a size of 100 nanometers or less.
As used herein, the expression "thermal welding" refers to a technique in which powder particles are injected into a torch lamp and sprayed onto a substrate. The particles gain high velocities and melt partially or completely during the flight path. A film is created by the solidification of droplets on the substrate surface. Examples of such techniques include plasma spray, arc spray and high speed oxy-fuel.
[0007]
As used herein, the expression "powder metallurgy" refers to a technique that transforms a bulk powder into a preform of a desired shape by a compaction or post-sintering sintering process. Compaction refers to the technique of applying pressure to a powder, such as cold uniaxial, cold isostatic or hot isostatic pressing. Shaping refers to a technique performed without the application of external pressure, such as powder filling or slurry casting.
[0008]
In another aspect, the present invention also provides a method for producing a powdered refractory hard alloy as described above. The method of the present invention comprises the following steps:
a) providing a first reagent selected from the group consisting of a transition metal and a transition metal-containing compound;
b) providing a second reagent selected from the group consisting of boron, boron-containing compounds, carbon and carbon-containing compounds;
c) zirconium, zirconium containing compound, hafnium, hafnium containing compound, vanadium, vanadium containing compound, niobium, niobium containing compound, tantalum, tantalum containing compound, chromium, chromium containing compound, molybdenum, molybdenum containing compound, manganese, manganese containing compound, Supplying an optional third reagent selected from the group consisting of tungsten, a tungsten-containing compound, cobalt and a cobalt-containing compound; and d) subjecting the first, second and third reagents to high energy ball milling, During the solid reaction and formed from agglomerates of each grain comprising nanocrystals of the refractory hard alloy of the formula (I) as defined above, having an average particle size of 0.1 to 30 μm. Causing the formation of particles that are present;
including.
[0009]
As used herein, the expression "high energy ball milling" refers to a ball milling process capable of forming said particles comprising nanocrystalline grains of a refractory hard alloy of formula (I) in about 40 hours.
[0010]
Description of the drawings In the accompanying drawings, FIG. 1 shows the X-ray diffraction of the powdered refractory hard alloy obtained in Example 1.
Typical examples of refractory hard metal embodiment <br/> formula invention (I) are, TiB 1.8, TiB 2, TiB 2.2, TiC, Ti 0.5 Zr 0.1 B 2, Ti 0.9 Zr 0.1 B 2 , Ti 0.5 Hf 0.5 B 2 and Zr 0.8 V 0.2 B 2 . TiB 2 is preferred.
Examples of suitable transition metals that can be used as the first reagent include titanium, chromium, zirconium, and vanadium. Titanium is preferred. TiH 2, TiAl 3, titanium-containing compounds such as TiB and TiCl 2 can also be used.
The above examples of suitable boron-containing compounds which may be used as the second reagent, AlB 2, AlB 12, BH 3, BN, VB, H 2 BO 3 and Na 2 B 4 O 7 and the like. It is also possible to use either a to carbide four boron of the boron-containing compound or carbon-containing compound (B 4 C).
The above Examples of suitable compounds which may be used as the third reagent, HfB 2, VB 2, NbB 2, TaB 2, CrB 2, MoB 2, MnB 2, Mo 2 B 5, W 2 B 5, CoB, ZrC , TaC, WC and HfC.
[0011]
According to a preferred embodiment, step (d) of the method of the invention is carried out on a vibrating ball mill operating at a frequency of 8 to 25 Hz, preferably about 17 Hz. 150-1500 r. p. m. , Preferably about 1000 r. p. m. It can also be performed with a rotary ball mill operating at a speed of.
According to another preferred embodiment, step (d) is performed under an inert gas, such as a gas atmosphere containing argon or helium, or under a reactive gas atmosphere, such as a gas atmosphere containing hydrogen, ammonia or hydrocarbons. Doing so saturates the dangling bonds, thereby preventing oxidation of the refractory hard alloy. An atmosphere of argon, helium or hydrogen is preferred. The particles can be coated with a protective film or a sacrificial element such as Mg or Ca can be mixed with the reagent. Further, a sintering aid such as Y 2 O 3 can be added during step (d).
[0012]
When titanium and boron or carbon certain of TiB 2 or TiC is present in stoichiometric amounts, it may use this two compounds as starting material. Therefore, they are subjected directly to high-energy ball milling to obtain particles having an average particle size of 0.1 to 30 μm, each particle being formed by agglomerates of grains containing TiB 2 or TiC nanocrystals, respectively. Can be formed.
The high energy ball milling described above can provide a powdered refractory hard alloy having either a non-stoichiometric or stoichiometric composition.
[0013]
The powdered refractory hard alloy of the present invention is suitable for producing electrodes by heat welding or powder metallurgy. Due to the properties of refractory hard alloys, toxicity and greenhouse gas emissions during metal electrolysis are reduced, and the life of the electrodes is extended, thus reducing maintenance costs. Narrower and more constant internal electrode distances are also possible, thereby reducing the electrode resistance drop.
[0014]
The invention will now be described by way of non-limiting examples.
Example 1
By ball milling 3.45 g titanium and 1.55 g boron in a hardened steel crucible using a SPEX 8000 ™ vibrating ball mill operating at a frequency of about 17 Hz and a ball to powder mass ratio of 4.5: 1. It was prepared TiB 2 powder. Operating under a controlled argon atmosphere, oxidation was prevented. The crucible was closed and sealed with a rubber O-ring. After 5 hours of high energy ball milling, a TiB 2 structure was formed as shown in the X-ray diffraction pattern in the accompanying drawings. Structure of TiB 2 is a hexagonal system having a space group P6 / mmm (191). The particle size varied between 1-5 μm and the crystal size measured by X-ray diffraction was about 30 nm.
[0015]
Example 2
A TiB 2 powder was produced under the same procedure and under the same operating conditions as described in Example 1, except that ball milling was performed for 20 hours instead of 5 hours. The resulting powder was similar to that obtained in Example 1. However, the crystal size was small (about 16 nm).
Example 3
Except for grinding titanium and graphite, a TiC powder was produced under the same procedure and under the same operating conditions as described in Example 1.
Example 4
TiB 2 powder was produced by ball milling titanium diboride under the same operating conditions as in Example 1 except that ball milling was performed for 20 hours instead of 5 hours. The initial structure was maintained, but the crystal size was reduced to 15 nm.
[0016]
Example 5
TiB 1.8 powder was prepared according to the same procedure described in Example 1 and under the same operating conditions, except that 3.6 g of titanium and 1.4 g of boron were ground.
Example 6
TiB 1.8 powder was prepared according to the same procedure described in Example 1 and under the same operating conditions, except that 3.4 g of titanium and 1.7 g of boron were ground.
Example 7
The Ti 0.5 Zr 0.5 B 2 powder was prepared according to the same procedure described in Example 1 except that 1.9 g of titanium, 3.1 g of zirconium diboride and 0.8 g of boron were ground. Manufactured under the same operating conditions.
[0017]
Example 8
The Ti 0.9 Zr 0.1 B 2 powder was prepared according to the same procedure as described in Example 1, except that 2.9 g of titanium, 0.6 g of zirconium and 1.5 g of boron were ground. Manufactured under conditions.
Example 9
The Ti 0.5 Hf 0.5 B 2 powder was prepared according to the same procedure described in Example 1, except that 0.9 g of titanium, 3.3 g of hafnium, and 0.8 g of boron were ground. Manufactured under conditions.
Example 10
The Zr 0.8 V 0.2 B 2 powder was prepared according to the same procedure described in Example 1, except that 3.5 g of zirconium, 0.5 g of vanadium, and 1.0 g of boron were ground. Manufactured under conditions.
[Brief description of the drawings]
FIG. 1 shows an X-ray diffraction of the powdered refractory hard alloy obtained in Example 1.

Claims (45)

０．１〜３０μｍの平均粒径を有し、かつそれぞれグレインの凝集物で形成されている粒子を含んでなる粉末形態の耐火硬質合金であって、各グレインが、次式：
ＡｘＢｙＸｚ （Ｉ）
（式中、Ａは遷移金属であり、Ｂはジルコニウム、ハフニウム、バナジウム、ニオビウム、タンタル、クロム、モリブデン、マンガン、タングステン及びコバルトから成る群より選択される金属であり、Ｘはホウ素又は炭素であり、ｘは０．１〜３の範囲、ｙは０〜３の範囲、かつｚは１〜６の範囲である）の耐火硬質合金のナノ結晶を含むことを特徴とする粉末形態の耐火硬質合金。A powdered refractory hard alloy having an average particle size of 0.1 to 30 [mu] m and comprising particles each formed of agglomerates of grains, each grain having the following formula:
A x B y X z (I )
Wherein A is a transition metal, B is a metal selected from the group consisting of zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, manganese, tungsten and cobalt, and X is boron or carbon. X is in the range of 0.1 to 3, y is in the range of 0 to 3 and z is in the range of 1 to 6). . Ａが、チタン、クロム、ジルコニウム及びバナジウムから成る群より選択される遷移金属である、請求項１に記載の粉末形態の耐火硬質合金。The powdered refractory hard alloy of claim 1, wherein A is a transition metal selected from the group consisting of titanium, chromium, zirconium and vanadium. Ａがチタンであり、Ｘがホウ素であり、かつｙが０である、請求項２に記載の粉末形態の耐火硬質合金。3. The powdered refractory hard alloy of claim 2, wherein A is titanium, X is boron, and y is 0. ｘが１であり、かつｚが１．８である、請求項３に記載の粉末形態の耐火硬質合金。 4. The powdered refractory hard alloy of claim 3, wherein x is 1 and z is 1.8. ｘが１であり、かつｚが２である、請求項３に記載の粉末形態の耐火硬質合金。 4. The powdered refractory hard alloy of claim 3, wherein x is 1 and z is 2. ｘが１であり、かつｚが２．２である、請求項３に記載の粉末形態の耐火硬質合金。 4. The powdered refractory hard alloy of claim 3, wherein x is 1 and z is 2.2. Ａがチタンであり、Ｘが炭素であり、かつｙが０である、請求項２に記載の粉末形態の耐火硬質合金。The powdered refractory hard metal alloy of claim 2, wherein A is titanium, X is carbon, and y is 0. ｘが１であり、かつｚが１である、請求項７に記載の粉末形態の耐火硬質合金。The powdered refractory hard alloy of claim 7, wherein x is 1 and z is 1. Ａがチタンであり、Ｂがジルコニウム又はハフニウムであり、Ｘがホウ素であり、かつｙが０以外である、請求項２に記載の粉末形態の耐火硬質合金。The powdered refractory hard alloy of claim 2, wherein A is titanium, B is zirconium or hafnium, X is boron and y is other than zero. Ｂがジルコニウムであり、ｘが０．５であり、ｙが０．５であり、かつｚが２である、請求項９に記載の粉末形態の耐火硬質合金。10. The powdered refractory hard alloy of claim 9, wherein B is zirconium, x is 0.5, y is 0.5, and z is 2. Ｂがジルコニウムであり、ｘが０．９であり、ｙが０．１であり、かつｚが２である、請求項９に記載の粉末形態の耐火硬質合金。10. The powdered refractory hard alloy of claim 9, wherein B is zirconium, x is 0.9, y is 0.1, and z is 2. Ｂがハフニウムであり、ｘが０．５であり、ｙが０．５であり、かつｚが２である、請求項２に記載の粉末形態の耐火硬質合金。The powdered refractory hard alloy of claim 2, wherein B is hafnium, x is 0.5, y is 0.5, and z is 2. Ａがジルコニウムであり、Ｂがバナジウムであり、Ｘがホウ素であり、かつｙが０以外である、請求項２に記載の粉末形態の耐火硬質合金。The powdered refractory hard alloy of claim 2 wherein A is zirconium, B is vanadium, X is boron, and y is other than zero. ｘが０．８であり、ｙが０．２であり、かつｚが２である、請求項１３に記載の粉末形態の耐火硬質合金。 14. The powdered refractory hard alloy of claim 13, wherein x is 0.8, y is 0.2, and z is 2. 前記平均粒径が、１〜５μｍの範囲である、請求項１に記載の粉末形態の耐火硬質合金。The powdered refractory hard alloy according to claim 1, wherein the average particle size is in a range of 1 to 5 μm. 請求項１に記載の粉末形態の耐火硬質合金の製造方法であって、以下の工程：
ａ）遷移金属及び遷移金属含有化合物から成る群より選択される第１試薬を供給する工程；
ｂ）ホウ素、ホウ素含有化合物、炭素及び炭素含有化合物から成る群より選択される第２試薬を供給する工程：
ｃ）ジルコニウム、ジルコニウム含有化合物、ハフニウム、ハフニウム含有化合物、バナジウム、バナジウム含有化合物、ニオビウム、ニオビウム含有化合物、タンタル、タンタル含有化合物、クロム、クロム含有化合物、モリブデン、モリブデン含有化合物、マンガン、マンガン含有化合物、タングステン、タングステン含有化合物、コバルト及びコバルト含有化合物から成る群より選択される任意の第３試薬を供給する工程；及び
ｄ）前記第１、第２及び第３試薬を高エネルギーボールミル粉砕に供し、それらの間に固体反応と、０．１〜３０μｍの平均粒径を有し、各粒子が請求項１に記載の式（Ｉ）の耐火硬質合金のナノ結晶を含んでなる各グレインの凝集物で形成されている粒子の形成とを引き起こす工程；
を含む方法。A method for producing a refractory hard alloy in powder form according to claim 1, comprising the following steps:
a) providing a first reagent selected from the group consisting of a transition metal and a transition metal-containing compound;
b) providing a second reagent selected from the group consisting of boron, boron containing compounds, carbon and carbon containing compounds:
c) zirconium, zirconium containing compound, hafnium, hafnium containing compound, vanadium, vanadium containing compound, niobium, niobium containing compound, tantalum, tantalum containing compound, chromium, chromium containing compound, molybdenum, molybdenum containing compound, manganese, manganese containing compound, Supplying an optional third reagent selected from the group consisting of tungsten, a tungsten-containing compound, cobalt and a cobalt-containing compound; and d) subjecting the first, second and third reagents to high energy ball milling, A solid reaction and an agglomerate of each grain having an average particle size of 0.1 to 30 μm, each particle comprising nanocrystals of the refractory hard alloy of formula (I) according to claim 1. Causing the formation of formed particles;
A method that includes 前記第１試薬が、チタン、クロム、ジルコニウム及びバナジウムから成る群より選択される遷移金属を含む、請求項１６に記載の方法。17. The method of claim 16, wherein said first reagent comprises a transition metal selected from the group consisting of titanium, chromium, zirconium and vanadium. 前記遷移金属がチタンである、請求項１７に記載の方法。The method according to claim 17, wherein the transition metal is titanium. 前記第１試薬が、ＴｉＨ２、ＴｉＡｌ３、ＴｉＢ及びＴｉＣｌ２から成る群より選択されるチタン含有化合物を含む、請求項１６に記載の方法。Wherein the first reagent, TiH 2, TiAl 3, are selected from TiB the group consisting of TiCl 2 comprising a titanium-containing compound The method of claim 16. 前記第２試薬がホウ素を含む、請求項１６に記載の方法。17. The method of claim 16, wherein said second reagent comprises boron. 前記第２試薬が、ＡｌＢ２、ＡｌＢ１２、ＢＨ３、ＢＮ、ＶＢ２、Ｈ２ＢＯ３及びＮａ２Ｂ４Ｏ７から成る群より選択されるホウ素含有化合物を含む、請求項１６に記載の方法。Said second reagent comprises AlB 2, AlB 12, BH 3 , BN, VB 2, H 2 BO 3 and Na 2 B 4 O 7 boron-containing compound selected from the group consisting of, according to claim 16 Method. 前記第２試薬が炭素を含む、請求項１６に記載の方法。17. The method of claim 16, wherein said second reagent comprises carbon. 前記第２試薬が炭化四ホウ素を含む、請求項１６に記載の方法。17. The method of claim 16, wherein said second reagent comprises tetraboron carbide. 前記第３試薬が、ＨｆＢ２、ＶＢ２、ＮｂＢ２、ＴａＢ２、ＣｒＢ２、ＭｏＢ２、ＭｎＢ２、Ｍｏ２Ｂ５、Ｗ２Ｂ５、ＣｏＢ、ＺｒＣ、ＴａＣ、ＷＣ及びＨｆＣから成る群より選択される化合物を含む、請求項１６に記載の方法。The third reagent, HfB 2, VB 2, NbB 2, TaB 2, CrB 2, MoB 2, MnB 2, Mo 2 B 5, W 2 B 5, CoB, ZrC, TaC, from the group consisting of WC and HfC 17. The method of claim 16, comprising a selected compound. 工程（ｄ）を、８〜２５Ｈｚの振動数で操作する振動ボールミル内で行う、請求項１６に記載の方法。17. The method of claim 16, wherein step (d) is performed in a vibrating ball mill operating at a frequency between 8 and 25 Hz. 前記振動ボールミルを約１７Ｈｚの振動数で操作する、請求項２５に記載の方法。26. The method of claim 25, wherein the vibrating ball mill operates at a frequency of about 17 Hz. 工程（ｄ）を、１５０〜１５００ｒ．ｐ．ｍ．の速度で操作する回転ボールミル内で行う、請求項１６に記載の方法。Step (d) is performed at 150 to 1500 r. p. m. 17. The method of claim 16, wherein the method is performed in a rotating ball mill operating at a speed of. 前記回転ボールミルを約１０００ｒ．ｐ．ｍ．の速度で操作する、請求項２７に記載の方法。The rotating ball mill is rotated at about 1000 rpm. p. m. 28. The method of claim 27, operating at a speed of. 工程（ｄ）を、不活性ガス雰囲気下で行う、請求項１６に記載の方法。17. The method according to claim 16, wherein step (d) is performed under an inert gas atmosphere. 前記不活性ガス雰囲気が、アルゴン又はヘリウムを含む、請求項２９に記載の方法。30. The method of claim 29, wherein said inert gas atmosphere comprises argon or helium. 工程（ｄ）を、反応性ガス雰囲気下で行う、請求項１６に記載の方法。17. The method according to claim 16, wherein step (d) is performed under a reactive gas atmosphere. 前記反応性ガス雰囲気が、水素、アンモニア又は炭化水素を含む、請求項３１に記載の方法。32. The method of claim 31, wherein the reactive gas atmosphere comprises hydrogen, ammonia, or a hydrocarbon. 工程（ｄ）を、約５時間行う、請求項１６に記載の方法。17. The method of claim 16, wherein step (d) is performed for about 5 hours. 工程（ｄ）の間に、焼結助剤を添加する、請求項１６に記載の方法。17. The method according to claim 16, wherein a sintering aid is added during step (d). 請求項５又は８に記載の粉末形態の耐火硬質合金の製造方法であって、ＴｉＢ２又はＴｉＣを高エネルギーボールミル粉砕に供し、０．１〜３０μｍの平均粒径を有し、各粒子がＴｉＢ２又はＴｉＣのナノ結晶を含んでなる各グレインの凝集物で形成されている粒子の形成を引き起こす工程を含む方法。A method of manufacturing a refractory hard metal in powder form according to claim 5 or 8, provided the TiB 2 or TiC to high-energy ball milling, a mean particle size of 0.1 to 30 [mu] m, each particle TiB which comprises the step of causing the formation of the particles being formed by aggregates of each grain comprising a nanocrystal of 2 or TiC. 前記高エネルギーボールミル粉砕を、８〜２５Ｈｚの振動数で操作する振動ボールミル内で行う、請求項３５に記載の方法。36. The method of claim 35, wherein the high energy ball milling is performed in a vibrating ball mill operating at a frequency between 8 and 25 Hz. 前記振動ボールミルを、約１７Ｈｚの振動数で操作する、請求項３６に記載の方法。37. The method of claim 36, wherein the vibrating ball mill operates at a frequency of about 17 Hz. 前記高エネルギーボールミル粉砕を、１５０〜１５００ｒ．ｐ．ｍ．の速度で操作する回転ボールミル内で行う、請求項３５に記載の方法。The high energy ball mill pulverization is performed at 150 to 1500 r. p. m. 36. The method of claim 35, wherein the method is performed in a rotating ball mill operating at a speed of. 前記回転ボールミルを、約１０００ｒ．ｐ．ｍ．の速度で操作する、請求項３８に記載の方法。The rotating ball mill is rotated at about 1000 rpm. p. m. 39. The method of claim 38, operating at a speed of. 前記高エネルギーボールミル粉砕を、不活性ガス雰囲気下で行う、請求項３５に記載の方法。The method according to claim 35, wherein the high energy ball milling is performed under an inert gas atmosphere. 前記不活性ガス雰囲気が、アルゴン又はヘリウムを含む、請求項４０に記載の方法。41. The method of claim 40, wherein said inert gas atmosphere comprises argon or helium. 前記高エネルギーボールミル粉砕を、反応性ガス雰囲気下で行う、請求項３５に記載の方法。The method according to claim 35, wherein the high energy ball milling is performed under a reactive gas atmosphere. 前記反応性ガス雰囲気が、水素、アンモニア又は炭化水素を含む、請求項４２に記載の方法。43. The method of claim 42, wherein said reactive gas atmosphere comprises hydrogen, ammonia or a hydrocarbon. 前記高エネルギーボールミル粉砕を、約２０時間行う、請求項３５に記載の方法。36. The method of claim 35, wherein the high energy ball milling is performed for about 20 hours. 前記高エネルギーボールミル粉砕の間に、焼結助剤を添加する、請求項３５に記載の方法。36. The method of claim 35, wherein a sintering aid is added during the high energy ball milling.
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