JPH0478584B2 - - Google Patents
Info
- Publication number
- JPH0478584B2 JPH0478584B2 JP58123855A JP12385583A JPH0478584B2 JP H0478584 B2 JPH0478584 B2 JP H0478584B2 JP 58123855 A JP58123855 A JP 58123855A JP 12385583 A JP12385583 A JP 12385583A JP H0478584 B2 JPH0478584 B2 JP H0478584B2
- Authority
- JP
- Japan
- Prior art keywords
- sintered body
- solid solution
- powder
- sintering
- hardness
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 150000001875 compounds Chemical class 0.000 claims description 39
- 229910052751 metal Inorganic materials 0.000 claims description 23
- 239000006104 solid solution Substances 0.000 claims description 21
- 239000000203 mixture Substances 0.000 claims description 15
- 238000000354 decomposition reaction Methods 0.000 claims description 10
- 238000001330 spinodal decomposition reaction Methods 0.000 claims description 9
- 229910052776 Thorium Inorganic materials 0.000 claims description 8
- 229910052735 hafnium Inorganic materials 0.000 claims description 8
- 229910052758 niobium Inorganic materials 0.000 claims description 8
- 229910052715 tantalum Inorganic materials 0.000 claims description 8
- 229910052720 vanadium Inorganic materials 0.000 claims description 8
- 229910052726 zirconium Inorganic materials 0.000 claims description 8
- 229910052719 titanium Inorganic materials 0.000 claims description 7
- 150000004767 nitrides Chemical class 0.000 claims description 6
- 230000002950 deficient Effects 0.000 claims description 2
- 239000000843 powder Substances 0.000 description 29
- 239000012071 phase Substances 0.000 description 24
- 238000005245 sintering Methods 0.000 description 23
- 239000002184 metal Substances 0.000 description 21
- 239000007858 starting material Substances 0.000 description 13
- 239000011230 binding agent Substances 0.000 description 10
- 238000005260 corrosion Methods 0.000 description 10
- 230000007797 corrosion Effects 0.000 description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- 239000000463 material Substances 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 6
- 239000002131 composite material Substances 0.000 description 6
- 238000002156 mixing Methods 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 5
- 239000011812 mixed powder Substances 0.000 description 5
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- 230000001590 oxidative effect Effects 0.000 description 5
- 238000001816 cooling Methods 0.000 description 4
- 238000005520 cutting process Methods 0.000 description 4
- 238000000227 grinding Methods 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- -1 iron group metals Chemical class 0.000 description 4
- 150000001247 metal acetylides Chemical class 0.000 description 4
- 238000000465 moulding Methods 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 238000004453 electron probe microanalysis Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000000737 periodic effect Effects 0.000 description 3
- 239000010935 stainless steel Substances 0.000 description 3
- 229910001220 stainless steel Inorganic materials 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 2
- 229920006311 Urethane elastomer Polymers 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000011195 cermet Substances 0.000 description 2
- 238000000280 densification Methods 0.000 description 2
- 239000008187 granular material Substances 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical compound CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 description 2
- 150000002736 metal compounds Chemical class 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229910052755 nonmetal Inorganic materials 0.000 description 2
- 239000012188 paraffin wax Substances 0.000 description 2
- 238000005191 phase separation Methods 0.000 description 2
- 238000010298 pulverizing process Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 210000004243 sweat Anatomy 0.000 description 2
- DSSYKIVIOFKYAU-XCBNKYQSSA-N (R)-camphor Chemical compound C1C[C@@]2(C)C(=O)C[C@@H]1C2(C)C DSSYKIVIOFKYAU-XCBNKYQSSA-N 0.000 description 1
- FFRBMBIXVSCUFS-UHFFFAOYSA-N 2,4-dinitro-1-naphthol Chemical compound C1=CC=C2C(O)=C([N+]([O-])=O)C=C([N+]([O-])=O)C2=C1 FFRBMBIXVSCUFS-UHFFFAOYSA-N 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- 241000723346 Cinnamomum camphora Species 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- CZMRCDWAGMRECN-UGDNZRGBSA-N Sucrose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO)O1 CZMRCDWAGMRECN-UGDNZRGBSA-N 0.000 description 1
- 229930006000 Sucrose Natural products 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229960000846 camphor Drugs 0.000 description 1
- 229930008380 camphor Natural products 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000001513 hot isostatic pressing Methods 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 235000014655 lactic acid Nutrition 0.000 description 1
- 239000004310 lactic acid Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229910052573 porcelain Inorganic materials 0.000 description 1
- 238000001272 pressureless sintering Methods 0.000 description 1
- 238000007639 printing Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 229910052979 sodium sulfide Inorganic materials 0.000 description 1
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000005720 sucrose Substances 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
Description
本発明は、実質的に金属相からなる結合相を含
有してなく、耐熱性、耐酸化性、耐摩耗性、耐食
性、熱伝導性及び電気伝導性の優れた硬質相から
なる高硬度焼結体に関する。
従来、周期律表の4a，5a，6a族の遷移金属中
にＣ，Ｎ，Ｏの非金属元素を固溶した侵入型化合
物は難焼結性材料であり、このままでは1600℃以
下の温度で緻密に焼結できないために鉄族金属を
添加して共晶反応による液相焼結を行い緻密化促
進と同時に強度を向上させた超硬合金が実用化さ
れている。この超硬合金、サーメツト等の複合合
金は、鉄族金属からなる結合相を有しているため
に高温高応力下で使用すると結合相の軟化に起因
して塑性変形が進行したり、耐摩耗性が低下した
り、又鉄族金属からなる結合相の熱膨張率と4a，
5a，6a族金属の化合物からなる硬質相の熱膨張
率との差に起因すると考えられる熱亀裂が生じた
り、更に化学薬品及び腐食性ガス雰囲気中で使用
すると結合相である鉄族金属が腐食して使用でき
なくなるという問題がある。
本発明の高硬度焼結体は、上記のような問題点
を解決したもので、実質的に金属からなる結合相
を含有してなく高硬度、低比重で熱伝導性、電気
伝導性、耐食性及び耐酸化性に優れた焼結体を提
供するものである。即ち本発明の高硬度焼結体
は、Ti，Zr，Hf，Ｖ，Nb，Ta，Thの炭化物、
窒化物、酸化物の中から選ばれた２種以上を組合
わせた固溶体化合物からなり、該固溶体化合物が
スピノーダル分解又はバイノーダル分解による変
調構造の組織になつている焼結体である。
本発明の高硬度焼結体は、Ti，Zr，Hf，Ｖ，
Nb，Ta，Thの炭化物、窒化物、酸化物の内、
金相学的に全率固溶（ここで記載の全率固溶と
は、スピノーダル分解又はバイノーダル分解が起
る組成成分比からなることを示す）する２種以上
を組合わせることによつてスピノーダル分解又は
バイノーダル分解を発生させ、実質的に金属から
なる結合相を含有してなくても1600℃以下の低い
温度で緻密な焼結体にして実用可能な靱性と高硬
度、低比重でしかも熱伝導性、電気伝導性、耐食
性及び耐酸化性に優れるようにしたものである。
Ti，Zr，Hf，Ｖ，Nb，Ta，Thの炭化物、窒化
物、酸化物の中の２種以上を組合わせてスピノー
ダル分解又はバイノーダル分解を発生しない組成
比では、略2000℃以上の高温焼結にする必要が生
じ得られる焼結体の結晶粒子は粗大化して焼結体
の諸特性を低下させるために金相学的に全率固溶
する２種の化合物の内、１種を５モル％以上存在
させる組成比にしてスピノーダル分解又はバイノ
ーダル分解を発生させることが望ましい。スピノ
ーダル分解又はバイノーダル分解を起こさせる組
成比にすると低温で緻密な焼結体になるために焼
結体の結晶粒子が微細となつて一層高硬度、高靱
性及び耐熱性の傾向が高まる。
スピノーダル分解又はバイノ−ダル分解による
変調構造の組織とは、金属及び／又は非金属の含
有量の異なつた２相以上の固溶体化合物が周期的
に繰り返して並んだ組織からなつている。具体的
には、例えばTiC−TiN−VC固溶体化合物の場
合、Ti及び／又はＶの含有量の多い固溶体化合
物と少ない固溶体化合物、もしくはＣ及び／又は
Ｎの含有量の多い固溶体化合物と少ない固溶体化
合物、あるいはこれらが両方組合わされた固溶体
化合物の中の２つ以上の固溶体化合物が存在し、
この２つ以上の固溶体化合物の相が周期的に繰り
返して並んだ組織である。
本発明の高硬度焼結体は、金属からなる結合相
を含有していないことから耐食性が著しく優れて
おり、4a族の金属化合物を主体にして窒素含有
量の多い焼結体にすることによつて美麗な黄金色
の色調になり、しかも高硬度で耐スクラツチ性に
優れており、低密度であることから時計用外装部
品、釣り具部品等の装飾品用部品に利用できる。
又、本発明の高硬度焼結体は、電気伝導性が優れ
ているために放電加工も容易であることから複雑
な形状の加工も可能で、耐食性、高硬度であるこ
とを加味するとノズル、メカニカルシール、サポ
ートホールド治具、印字ピン用ガイド、摺動部材
等並びに窒素含有量の多い焼結体は、ガラス溶解
用モールド、レンズ成形用耐熱モールド、磁器ヘ
ツド基盤、テープカツター等と耐摩耗性材料とし
て利用できる。更に本発明の高硬度焼結体は、熱
伝導性が優れており、金属からなる結合相を含有
していないので被削材との耐反応性も良いことか
ら硬質黒鉛、樹脂等の非鉄金属の切削用工具にも
利用できるものである。
本発明の高硬度焼結体の製造するための出発原
料は、微細粒子を使用する程焼結過程において化
合物中の金属原子及び侵入型の非金属原子が相互
拡散してスピノーダル分解又はバイノーダル分解
による相分離現象を起し易くなつて、焼結を促進
するために一層低温での焼結が可能となり、この
ために焼結体の結晶粒子が微細になつて高硬度、
高靱性化の傾向が高くなる。このことから出発原
料は、10μm以下特に0.1μm以下のものが望まし
いが酸化等が生じるための取扱い上から2μm以下
のものが望ましい。出発原料が粗粒のときは、混
合粉砕を強化すればよいがこのときには不純物の
混入が多くなる傾向になるので用途によつて使い
分ける必要がある。出発原料の構成は、(a)Ti，
Zr，Hf，Ｖ，Nb，Ta，Thの金属粉末の中の２
種以上からなる混合粉末を用いて雰囲気調整によ
り反応焼結する方法、(b)Ti，Zr，Hf，Ｖ，Nb，
Ta，Thの金属粉末の１種以上とTi，Zr，Hf，
Ｖ，Nb，Ta，Thの炭化物粉末、窒化物粉末、
酸化物粉末及びこれらの相互固溶体化合物粉末の
１種以上とからなる混合粉末を用いて雰囲気調整
により反応焼結する方法、(c)Ti，Zr，Hf，Ｖ，
Nb，Ta，Thの炭化物、窒化物、酸化物の単一
化合物粉末及びこれらの相互固溶体化合物粉末か
らなる混合粉末を用いて非酸化性雰囲気中で焼結
する方法が考えられる。この内(a)，(b)の金属粉末
の混入したものを出発原料とするのは、反応焼結
時間が長くなつたり、焼結体の中に金属が残存し
て耐食性及び硬さを低下させるために(c)の構成を
出発原料とするのが望ましい。(c)の構成の中でも
複合化合物粉末のみを出発原料とするよりも複合
化合物粉末と単一化合物粉末又は単一化合物粉末
と単一化合物粉末を出発原料とする組合わせがよ
く、特に焼結過程での固相拡散による緻密化と同
時にスピノーダル分解又はバイノーダル分解によ
る相分離現象を生じさせて低温で焼結し、微細粒
子による変調構造の組織からなる焼結体にするた
めには２種以上の単一化合物粉末を出発原料とし
て使用する。さらに、例えばこの出発原料を使用
し、焼結条件の制御、具体的には焼結温度に保持
した後、焼結温度から約800℃まで冷却速度を速
めて、約800℃から再度1200〜1450℃まで昇温す
ると、より速やかに変調構造の組織からなる焼結
体にすることができる。この出発原料として使用
する単一化合物粉末又は複合化合物粉末は、金属
元素と非金属元素のモル比が同一である化学量論
組成であつても侵型元素である炭素、窒素、酸素
の非金属が欠乏又は過剰に固溶した非化学量論組
織であつても本発明の高硬度焼結体が得られる。
本発明の高硬度焼結体の製造工程の内、出発原
料の混合粉砕は、ステンレス製容器、超硬合金を
内張りした容器又はウレタンゴムを内張りした容
器を使用してステンレス製ボール、超硬合金製ボ
ール又は表面被覆したボールと共に混合粉砕す
る。粉砕効果を高めて出発原料を微細化するに
は、ステンレス製容器又は超硬合金を内張りした
容器を使用して超硬合金製ボールと共に混合粉砕
するのがよく、又、アセトン、ヘキサン、ベンゼ
ン、アルコール等の有機溶媒を加えて湿式混合粉
砕するのがよい。耐食性及び高温での耐摩耗性を
利用する用途向け等で主として金属からなる不純
物を考慮する必要があるときはウレタンゴムで内
張りした容器を使用して表面被覆したボールと共
に混合するのがよい。不純物は、混合粉砕工程か
ら混入する比率が高く、混合粉砕工程で使用する
超硬合金の内、超硬合金の主成分である4a，5a，
6a族金属化合物が不純物として混入するのは割
合問題がないのに対して超硬合金の結合相である
鉄族金属の混入は２体積％以下出来れば１体積％
以下にするのが望ましい。
本発明の高硬度焼結体の製造工程の内、混合粉
末の成形は、混合粉砕した粉末を黒鉛モールドに
充填して非酸化性雰囲気中でホツトプレスする方
法、又は混合粉砕した粉末にパラフイン、カンフ
ア等の成形助剤を添加して必要ならば顆粒状にし
た後金型モールドに充填して加圧成形したり、も
しくはラバープレス等の静水圧加圧によつて成形
する。このようにして成形した粉末圧粉体を直接
焼結したり、又は粉末圧粉体を焼結温度よりも低
い温度で予備焼結した後切断、研削、切削等の機
械加工を施してから焼結することもできる。
本発明の高硬度焼結体の製造工程の内、焼結
は、非酸化性雰囲気中で無加圧焼結又は加圧焼結
したり並びに減圧状又は真空中で焼結することが
できる。特に窒素元素の含有した焼結体を得ると
きには、脱窒の防止からN2ガスを含有した非酸
化性雰囲気中で焼結することが望ましい。更に上
記条件で焼結したものを熱間静水圧加圧法
（HIP）によつて再処理することにより一層緻密
で高靱性の焼結体にすることもできる。
以下に実施例に従つて本発明の高硬度焼結体を
具体的に説明する。
実施例 １
平均粒度0.2〜3μmの各種単一化合物粉末を所
定の割合に配合し、この配合粉末に３〜５％のパ
ラフインを成形助剤として添加後アセトン溶媒
中、WC基超硬合金製ボールを用いてステンレス
容器にて混合粉砕した。得られた混合粉末から溶
媒を蒸発乾燥後、この混合粉末を1t／cm2〜5t／cm2
の加圧力で成形し、10-3〜10-2mmＨｇの真空又は
非酸化性ガス雰囲気中1300℃〜1600℃の温度で30
〜90分保持後、このそれぞれの焼結温度から800
℃までに冷却する冷却速度を約300℃／分とし、
800℃から再度1300〜1450℃（焼結温度より100〜
150℃低温に）に昇温し、10〜15時間保持して本
発明品を得た。各試料の配合組成及び焼結条件を
第１表に示し、得られた各試料の焼結体の諸特性
を第２表に示した。
比較として、焼結温度から炉冷（約50℃／分）
し、比較品１及び２を得た。この比較品１及び２
の配合組成及び焼結条件を第１表に、焼結体の諸
特性を第２表に併記した。
The present invention is a high-hardness sintered material that does not contain a binder phase that is substantially made of a metal phase and is made of a hard phase that has excellent heat resistance, oxidation resistance, abrasion resistance, corrosion resistance, thermal conductivity, and electrical conductivity. Regarding the body. Conventionally, interstitial compounds in which nonmetallic elements such as C, N, and O are dissolved in transition metals of groups 4a, 5a, and 6a of the periodic table are difficult-to-sinter materials, and as they are, they cannot be sintered at temperatures below 1600℃. Because it cannot be sintered densely, cemented carbide alloys have been put into practical use in which iron group metals are added and liquid phase sintering is performed through eutectic reaction to promote densification and improve strength at the same time. Composite alloys such as cemented carbide and cermets have a binder phase made of iron group metals, so when used under high temperature and high stress conditions, plastic deformation progresses due to the softening of the binder phase, resulting in poor wear resistance. The thermal expansion coefficient of the binder phase made of iron group metal and 4a,
Thermal cracks may occur, which is thought to be due to the difference in thermal expansion coefficient of the hard phase consisting of compounds of group 5a and 6a metals.Furthermore, if used in a chemical or corrosive gas atmosphere, the iron group metal, which is the binder phase, may corrode. The problem is that it becomes unusable. The high-hardness sintered body of the present invention solves the above-mentioned problems, and does not contain a binder phase substantially made of metal, has high hardness, low specific gravity, and has good thermal conductivity, electrical conductivity, and corrosion resistance. and a sintered body with excellent oxidation resistance. That is, the high hardness sintered body of the present invention contains carbides of Ti, Zr, Hf, V, Nb, Ta, and Th,
It is a sintered body made of a solid solution compound that is a combination of two or more selected from nitrides and oxides, and the solid solution compound has a modulated structure structure due to spinodal decomposition or binodal decomposition. The high hardness sintered body of the present invention includes Ti, Zr, Hf, V,
Among carbides, nitrides, and oxides of Nb, Ta, and Th,
Spinodal decomposition or binodal decomposition or It generates binodal decomposition and can be made into a compact sintered body at a low temperature of 1600℃ or less even without containing a binder phase consisting essentially of metal.It has toughness, high hardness, low specific gravity, and thermal conductivity. , which has excellent electrical conductivity, corrosion resistance, and oxidation resistance.
If two or more of the carbides, nitrides, and oxides of Ti, Zr, Hf, V, Nb, Ta, and Th are combined at a composition ratio that does not cause spinodal decomposition or binodal decomposition, high-temperature sintering at approximately 2000°C or higher Since it becomes necessary to sinter, the crystal grains of the resulting sintered body become coarse and the various properties of the sintered body deteriorate, one of the two types of compounds that are completely dissolved in metallurgy is added at 5 mol %. It is desirable to cause spinodal decomposition or binodal decomposition to occur at a composition ratio greater than or equal to the above. When the composition ratio is set to cause spinodal decomposition or binodal decomposition, a dense sintered body is formed at a low temperature, so that the crystal grains of the sintered body become finer and tend to have higher hardness, higher toughness, and higher heat resistance. The modulated structure resulting from spinodal decomposition or binodal decomposition consists of a structure in which solid solution compounds of two or more phases with different metal and/or nonmetal contents are arranged in a periodic manner. Specifically, for example, in the case of a TiC-TiN-VC solid solution compound, a solid solution compound with a high content of Ti and/or V and a solid solution compound with a low content, or a solid solution compound with a high content of C and/or N and a solid solution compound with a low content. , or there are two or more solid solution compounds in the solid solution compound in which both of these are combined,
It is a structure in which phases of two or more solid solution compounds are arranged in a periodic manner. The high-hardness sintered body of the present invention has extremely excellent corrosion resistance because it does not contain a metal binder phase, and it is possible to make the sintered body mainly composed of group 4a metal compounds and with a high nitrogen content. As a result, it has a beautiful golden color, has high hardness and excellent scratch resistance, and has a low density, so it can be used for decorative parts such as watch exterior parts and fishing gear parts.
In addition, the high hardness sintered body of the present invention has excellent electrical conductivity and is easy to perform electric discharge machining, so it is possible to process complicated shapes. Mechanical seals, support holding jigs, guides for printing pins, sliding parts, etc., as well as sintered bodies with high nitrogen content, are used as wear-resistant materials for glass melting molds, heat-resistant molds for lens molding, porcelain head bases, tape cutters, etc. It can be used as Furthermore, the high-hardness sintered body of the present invention has excellent thermal conductivity, and since it does not contain a metal binder phase, it has good reaction resistance with work materials, so it can be used with non-ferrous metals such as hard graphite and resin. It can also be used for cutting tools. The starting material for producing the high-hardness sintered body of the present invention is such that the finer particles are used, the more metal atoms and interstitial nonmetal atoms in the compound interdiffuse during the sintering process, resulting in spinodal decomposition or binodal decomposition. This makes it easier for phase separation to occur, making it possible to sinter at even lower temperatures to promote sintering, which results in finer crystal grains in the sintered body, resulting in higher hardness and higher hardness.
The tendency towards higher toughness increases. For this reason, it is desirable that the starting material has a diameter of 10 μm or less, especially 0.1 μm or less, but it is preferably 2 μm or less from the viewpoint of handling since oxidation may occur. When the starting material is coarse particles, the mixing and pulverization may be strengthened, but since this tends to increase the amount of impurities mixed in, it is necessary to use them appropriately depending on the purpose. The composition of the starting materials is (a) Ti,
2 in metal powders of Zr, Hf, V, Nb, Ta, Th
A method of reaction sintering by adjusting the atmosphere using a mixed powder consisting of more than 1 species, (b) Ti, Zr, Hf, V, Nb,
One or more types of Ta, Th metal powder and Ti, Zr, Hf,
V, Nb, Ta, Th carbide powder, nitride powder,
A method of reaction sintering by adjusting the atmosphere using a mixed powder consisting of an oxide powder and one or more of these mutual solid solution compound powders, (c) Ti, Zr, Hf, V,
A possible method is to sinter in a non-oxidizing atmosphere using a powder mixture of single compound powders of carbides, nitrides, and oxides of Nb, Ta, and Th, and powders of mutual solid solution compounds thereof. Among these, using materials mixed with metal powder (a) and (b) as starting materials may result in a longer reaction sintering time, or may cause metals to remain in the sintered body, reducing corrosion resistance and hardness. In order to achieve this, it is desirable to use the composition (c) as a starting material. Among configurations (c), a combination of a composite compound powder and a single compound powder, or a combination of a single compound powder and a single compound powder as a starting material is better than using only a composite compound powder as a starting material, especially during the sintering process. In order to produce a sintered body with a modulated structure of fine particles by sintering at a low temperature by causing a phase separation phenomenon by spinodal decomposition or binodal decomposition at the same time as densification by solid phase diffusion, two or more types of A single compound powder is used as starting material. Furthermore, for example, using this starting material, controlling the sintering conditions, specifically holding it at the sintering temperature, increasing the cooling rate from the sintering temperature to about 800 °C, and then increasing the cooling rate from about 800 °C to 1200 to 1450 °C again. When the temperature is raised to .degree. C., a sintered body having a modulated structure can be formed more quickly. Even if the single compound powder or composite compound powder used as the starting material has a stoichiometric composition in which the molar ratio of metallic elements and nonmetallic elements is the same, the nonmetallic powder of carbon, nitrogen, and oxygen, which are erosive elements, The high hardness sintered body of the present invention can be obtained even if it has a non-stoichiometric structure in which the solid solution is deficient or excessive. In the manufacturing process of the high-hardness sintered body of the present invention, the starting materials are mixed and pulverized using a stainless steel container, a container lined with cemented carbide, or a container lined with urethane rubber. Mix and grind together with manufactured balls or surface-coated balls. In order to improve the grinding effect and make the starting materials finer, it is best to use a stainless steel container or a container lined with cemented carbide to mix and grind together with cemented carbide balls. It is preferable to add an organic solvent such as alcohol and perform wet mixing and pulverization. When it is necessary to consider impurities mainly made of metal, such as for applications that utilize corrosion resistance and high-temperature abrasion resistance, it is best to use a container lined with urethane rubber and mix with surface-coated balls. A high proportion of impurities are mixed in during the mixing and grinding process, and among the cemented carbide used in the mixing and grinding process, 4a, 5a, which is the main component of cemented carbide,
While there is no problem with the ratio of group 6a metal compounds mixed as impurities, the mixing of iron group metals, which are the binder phase of cemented carbide, should be 2% by volume or less, preferably 1% by volume.
It is desirable to do the following. In the manufacturing process of the high-hardness sintered body of the present invention, the mixed powder can be formed by filling the mixed and pulverized powder into a graphite mold and hot pressing it in a non-oxidizing atmosphere, or by adding paraffin or camphor to the mixed and pulverized powder. If necessary, it is made into granules by adding a molding aid such as, for example, granules, and then filled into a metal mold and molded under pressure, or molded by isostatic pressure using a rubber press or the like. The powder compact formed in this way can be directly sintered, or the powder compact can be pre-sintered at a temperature lower than the sintering temperature and then subjected to mechanical processing such as cutting, grinding, cutting, etc., and then sintered. It can also be tied. In the manufacturing process of the high-hardness sintered body of the present invention, sintering can be performed by pressureless sintering or pressure sintering in a non-oxidizing atmosphere, or by sintering under reduced pressure or in a vacuum. Particularly when obtaining a sintered body containing nitrogen element, it is desirable to sinter in a non-oxidizing atmosphere containing N 2 gas to prevent denitrification. Furthermore, a sintered body sintered under the above conditions can be reprocessed by hot isostatic pressing (HIP) to produce a sintered body that is even denser and has higher toughness. EXAMPLES The high-hardness sintered body of the present invention will be specifically described below with reference to Examples. Example 1 Various single compound powders with an average particle size of 0.2 to 3 μm were blended in a predetermined ratio, and after adding 3 to 5% paraffin as a molding aid to the blended powder, a WC-based cemented carbide ball was formed in an acetone solvent. The mixture was mixed and ground in a stainless steel container. After the solvent is evaporated and dried from the obtained mixed powder, this mixed powder is 1 t/cm 2 to 5 t/cm 2
Molding at a pressure of 10 -3 to 10 -2 mmHg or a non-oxidizing gas atmosphere at a temperature of 1300℃ to 1600℃ for 30 minutes.
After holding for ~90 min, this respective sintering temperature is
The cooling rate to cool down to ℃ is approximately 300℃/min,
From 800℃ again to 1300~1450℃ (100~100℃ higher than sintering temperature)
The temperature was raised to 150° C.) and maintained for 10 to 15 hours to obtain a product of the present invention. Table 1 shows the composition and sintering conditions of each sample, and Table 2 shows the properties of the sintered body of each sample. For comparison, furnace cooling (approximately 50℃/min) from sintering temperature
Comparative products 1 and 2 were obtained. These comparative products 1 and 2
The compounding composition and sintering conditions are listed in Table 1, and the properties of the sintered body are listed in Table 2.
【表】【table】
【表】
第２表に示した諸特性の内、耐食性試験は塩化
ナトリウム、硫化ナトリウム、尿素、シヨ糖、ア
ンモニア水、乳酸からなるPH3.9〜5.0に調整し
た人工汗に各試料を浸漬して鏡面研摩面の腐食状
態を観察したものである。
尚、第２表の本発明品１〜９及び比較品１〜２
の組織構造をEPMA分析により調べたところ、
本発明品１〜９は、２相以上の固溶体化合物が規
則的に配列されているのに対し、比較品１及び２
は全体が均一な１相からなつていた。
実施例 ２
平均粒度0.2〜3μmの各種単一化合物粉末及び
複合化合物粉末を所定の割合に配合し、実施例１
と同様にして焼結体を得た。各試料の配合組成及
び焼結条件を第３表に示し、得られた各試料の焼
結体の諸特性を実施例１と同様にして求め、その
結果を第４表に示した。
EPMA分析により調べた所、第４表の本発明
品10〜14は２相以上の固溶体化合物が規則的に配
列されているのに対し、比較品３は全体が均一な
１相からなつていた。[Table] Among the various properties shown in Table 2, the corrosion resistance test was performed by immersing each sample in artificial sweat containing sodium chloride, sodium sulfide, urea, sucrose, aqueous ammonia, and lactic acid, adjusted to a pH of 3.9 to 5.0. The corrosion state of the mirror-polished surface was observed. In addition, the present invention products 1 to 9 and comparative products 1 to 2 in Table 2
When the organizational structure of the was investigated by EPMA analysis, it was found that
Inventive products 1 to 9 have solid solution compounds of two or more phases arranged regularly, whereas comparative products 1 and 2
The whole consisted of one uniform phase. Example 2 Various single compound powders and composite compound powders with an average particle size of 0.2 to 3 μm were blended at a predetermined ratio, and Example 1
A sintered body was obtained in the same manner as above. The composition and sintering conditions of each sample are shown in Table 3, and the various properties of the sintered body of each sample obtained were determined in the same manner as in Example 1, and the results are shown in Table 4. When investigated by EPMA analysis, it was found that inventive products 10 to 14 in Table 4 had two or more phases of solid solution compounds arranged regularly, whereas comparative product 3 consisted of one homogeneous phase as a whole. .
【表】【table】
【表】
実施例 ３
平均粒度0.5〜5μmの不定比化合物からなる単
一化合物粉末及び複合化合物粉末を所定の割合に
配合し、実施例１と同様にして焼結体を得た。各
試料の配合組成及び焼結条件を第５表に示し、得
られた各試料の焼結体の諸特性を実施例１と同様
にして求め、その結果を第６表に示した。
EPMA分析により調べた所、第６表の本発明
品15〜21は２相以上の固溶体化合物が規則的に配
列されているのに対し、比較品４，５は全体が均
一な１相からなつていた。[Table] Example 3 A sintered body was obtained in the same manner as in Example 1 by blending a single compound powder and a composite compound powder made of non-stoichiometric compounds with an average particle size of 0.5 to 5 μm in a predetermined ratio. The composition and sintering conditions of each sample are shown in Table 5, and the various properties of the sintered body of each sample obtained were determined in the same manner as in Example 1, and the results are shown in Table 6. According to EPMA analysis, inventive products 15 to 21 in Table 6 have solid solution compounds of two or more phases arranged regularly, whereas comparative products 4 and 5 consist of a uniform single phase throughout. was.
【表】【table】
【表】
以上実施例１，２，３と比較に市販の超硬合金
及びサーメツトを人工汗による耐食試験を行つた
ところ市販の超硬合金及びサーメツトは金属結合
相が腐食して曇りが生じた。又実施例１の試料番
号８，９、実施例２の試料番号14、実施例３の試
料番号21の焼結体の鏡面状態は、美麗な黄金色系
の色調であつた。本発明の２相以上でなる変調構
造組織の焼結体は、従来の１相の固溶体化合物の
焼結体に比べて硬度、抵抗力、破壊靱性値及びヤ
ング率が顕著に高く優れていた。このような諸特
性から本発明の高硬度焼結体は、装飾品用材料、
切削工具用部品及び種々の耐摩耗用部品にと産業
上応用範囲の広い材料である。[Table] In comparison with Examples 1, 2, and 3, commercially available cemented carbide and cermet were subjected to a corrosion resistance test using artificial sweat. As a result, the commercially available cemented carbide and cermet were cloudy due to corrosion of the metal bonding phase. . The mirror surfaces of the sintered bodies of sample numbers 8 and 9 of Example 1, sample number 14 of Example 2, and sample number 21 of Example 3 had a beautiful golden yellow tone. The sintered body of the present invention having a modulated structure consisting of two or more phases had significantly higher hardness, resistance, fracture toughness, and Young's modulus than the conventional sintered body of a single-phase solid solution compound. Due to these characteristics, the high hardness sintered body of the present invention can be used as a material for decorative items,
It is a material with a wide range of industrial applications, including parts for cutting tools and various wear-resistant parts.
Claims (1)
窒化物及び酸化物の中から選ばれた２種以上でな
る固溶体化合物からなり、該固溶体化合物がスピ
ノーダル分解又はバイノーダル分解による変調構
造の組織になつていることを特徴とする高硬度焼
結体。 ２ 上記固溶体化合物が金属元素に対して非金属
元素の欠乏又は過剰である非化学量論組成からな
ることを特徴とする特許請求の範囲第１項記載の
高硬度焼結体。[Claims] 1 Carbide of Ti, Zr, Hf, V, Nb, Ta, Th,
A high-hardness sintered body comprising a solid solution compound composed of two or more selected from nitrides and oxides, the solid solution compound having a modulated structure structure due to spinodal decomposition or binodal decomposition. 2. The high-hardness sintered body according to claim 1, wherein the solid solution compound has a non-stoichiometric composition in which nonmetallic elements are deficient or in excess of metallic elements.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58123855A JPS6016867A (en) | 1983-07-07 | 1983-07-07 | High hardness sintered body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58123855A JPS6016867A (en) | 1983-07-07 | 1983-07-07 | High hardness sintered body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6016867A JPS6016867A (en) | 1985-01-28 |
| JPH0478584B2 true JPH0478584B2 (en) | 1992-12-11 |
Family
ID=14871061
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58123855A Granted JPS6016867A (en) | 1983-07-07 | 1983-07-07 | High hardness sintered body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6016867A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60118674A (en) * | 1983-11-30 | 1985-06-26 | 東芝タンガロイ株式会社 | Heat resistant high hardness sintered body |
| US4910171A (en) * | 1987-03-26 | 1990-03-20 | Agency Of Industrial Science And Technology | Titanium hafnium carbide-boride metal based ceramic sintered body |
| JP7226446B2 (en) * | 2018-07-17 | 2023-02-21 | 住友電気工業株式会社 | sintered body |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5426810A (en) * | 1977-08-01 | 1979-02-28 | Sumitomo Electric Industries | Sintered body for tool and method of making same |
-
1983
- 1983-07-07 JP JP58123855A patent/JPS6016867A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5426810A (en) * | 1977-08-01 | 1979-02-28 | Sumitomo Electric Industries | Sintered body for tool and method of making same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6016867A (en) | 1985-01-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4320204A (en) | Sintered high density boron carbide | |
| EP2165990B1 (en) | Dense boron carbide ceramic and process for producing the same | |
| EP0170889B1 (en) | Zrb2 composite sintered material | |
| JP2628200B2 (en) | TiCN-based cermet and method for producing the same | |
| JPS6159391B2 (en) | ||
| US7648675B2 (en) | Reaction sintered zirconium carbide/tungsten composite bodies and a method for producing the same | |
| JPH0478584B2 (en) | ||
| JP2863829B2 (en) | High toughness, high strength, high hardness alumina-based composite material | |
| JPH07502072A (en) | Boron carbide-copper cermet and its manufacturing method | |
| JP3213903B2 (en) | Tantalum carbide based sintered body and method for producing the same | |
| JPS63286549A (en) | Nitrogen-containing titanium carbide-base sintered alloy having excellent resistance to plastic deformation | |
| JPS6059195B2 (en) | Manufacturing method of hard sintered material with excellent wear resistance and toughness | |
| JP2684250B2 (en) | Silicon nitride sintered body and method for producing the same | |
| JPH0687656A (en) | Sintered compact based on tantalum-containing multiple compound and its production | |
| JPH03290356A (en) | Aluminum oxide based ceramics having high toughness and strength and production thereof | |
| JP2001179508A (en) | Cutting tool | |
| JP3366696B2 (en) | Manufacturing method of high strength cermet | |
| JPS60103148A (en) | Boride-base high-strength sintered hard material | |
| JPS60131867A (en) | High abrasion resistance superhard material | |
| JPH0547509B2 (en) | ||
| JP2782524B2 (en) | High density phase boron nitride based reaction sintered body and method for producing the same | |
| JPH0559481A (en) | Sintered hard alloy having high hardness | |
| JPH0545549B2 (en) | ||
| KR820001538B1 (en) | Process for preparing titanium carbide-tungsten carbide base powder for cemented carbide alloys | |
| JPH09239605A (en) | Ticn group cermet tool and its manufacture |