JPH08311584A - Refractory superalloy - Google Patents
Refractory superalloyInfo
- Publication number
- JPH08311584A JPH08311584A JP7286135A JP28613595A JPH08311584A JP H08311584 A JPH08311584 A JP H08311584A JP 7286135 A JP7286135 A JP 7286135A JP 28613595 A JP28613595 A JP 28613595A JP H08311584 A JPH08311584 A JP H08311584A
- Authority
- JP
- Japan
- Prior art keywords
- alloy
- superalloy
- iridium
- melting point
- tantalum
- 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.)
- Granted
Links
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- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は、高融点超合金に関す
るものである。さらに詳しくは、この発明は、発電用ガ
スタービン、ジェットエンジン、ロケットエンジン等の
タービンブレード、タービンベーン等に用いられる耐熱
部材として有用な高融点超合金に関するものである。FIELD OF THE INVENTION This invention relates to high melting point superalloys. More specifically, the present invention relates to a high melting point superalloy useful as a heat-resistant member used for turbine blades and turbine vanes of power generation gas turbines, jet engines, rocket engines and the like.
【０００２】[0002]
【従来の技術とその課題】従来より、タービンブレード
やタービンベーン等の高温機器に用いられる耐熱部材と
してはＮｉ基超合金が用いられている。このＮｉ基超合
金の融点は１３００℃前後であり、従って、実用的な強
度を有することのできる温度範囲、つまり耐用温度は１
１００℃程度である。しかしながら、発電用ガスタービ
ン、ジェットエンジン、ロケットエンジン等の高温機器
の出力や熱効率をさらに向上させるためには、燃焼ガス
温度を上昇させなければならず、このためには従来より
用いられているＮｉ基超合金の耐用温度１１００℃より
さらに高い耐用温度を有する耐熱部材が必要である。2. Description of the Related Art Conventionally, Ni-base superalloys have been used as heat-resistant members used in high-temperature equipment such as turbine blades and turbine vanes. The melting point of this Ni-base superalloy is around 1300 ° C. Therefore, the temperature range within which it has practical strength, that is, the service temperature is 1
It is about 100 ° C. However, in order to further improve the output and thermal efficiency of high-temperature equipment such as a gas turbine for power generation, a jet engine, and a rocket engine, it is necessary to raise the combustion gas temperature. There is a need for a heat-resistant member having a service temperature higher than the service temperature of the base superalloy of 1100 ° C.
【０００３】従来より、このような高い耐用温度を有す
る耐熱部材としてタングステン、ニオブ、モリブデン、
タンタル等の高融点合金が研究されている。しかしなが
ら、これらの合金は、真空中や不活性ガス中など酸化の
生じない雰囲気中においては十分な高温強度を有する
が、大気中や燃焼ガス中など酸化の生じる雰囲気中にお
いては急速に酸化消耗してしまうため上記のような高温
機器の部材としては用いることができないという欠点が
ある。Conventionally, as heat resistant members having such a high service temperature, tungsten, niobium, molybdenum,
High melting point alloys such as tantalum have been studied. However, these alloys have sufficient high-temperature strength in an atmosphere where oxidation does not occur, such as in vacuum or in an inert gas, but are rapidly consumed by oxidation in an atmosphere where oxidation occurs, such as in the air or in combustion gas. Therefore, there is a drawback that it cannot be used as a member of the above high temperature equipment.
【０００４】そこでこの発明は、上記のような従来技術
の欠点を解決するために創案されたものであり、従来の
超合金よりもさらに高い耐用温度の高温強度特性と、さ
らに優れた耐酸化特性とを有する、新しい高融点超合金
を提供することを目的としている。Therefore, the present invention was devised in order to solve the above-mentioned drawbacks of the prior art, and has a high temperature strength property with a higher service temperature and a further excellent oxidation resistance property than conventional superalloys. It is intended to provide a new high melting point superalloy having
【０００５】[0005]
【課題を解決するための手段】この発明は、上記の課題
を解決するものとして、イリジウム、ロジウムまたはこ
れらの混合物に、ニオブ、タンタル、ハフニウム、ジル
コニウム、ウラン、バナジウム、チタンおよびアルミニ
ウムの１種または２種以上の元素が添加された合金であ
って、ＦＣＣ構造とＬ１2 構造との２つの結晶を有する
ことを特徴とする高融点超合金を提供する。In order to solve the above-mentioned problems, the present invention provides iridium, rhodium or a mixture thereof with one of niobium, tantalum, hafnium, zirconium, uranium, vanadium, titanium and aluminum, or Provided is a high melting point superalloy which is an alloy to which two or more elements are added and which has two crystals of an FCC structure and an L1 2 structure.
【０００６】またこの発明は、上記超合金において、ニ
オブ、タンタル、ハフニウム、ジルコニウム、ウラン、
バナジウム、チタンおよびアルミニウムの１種または２
種以上のイリジウムへの添加量を２原子％以上２２原子
％以下とすることもその態様としている。The present invention also provides the above superalloys containing niobium, tantalum, hafnium, zirconium, uranium,
One or two of vanadium, titanium and aluminum
It is also an aspect that the amount of iridium added is 2 at% or more and 22 at% or less.
【０００７】[0007]
【作用】この発明においては、上記の通り、イリジウ
ム、ロジウムまたはこれらの混合物に、ニオブ、タンタ
ル、ハフニウム、ジルコニウム、ウラン、バナジウム、
チタン、アルミニウムを単独に、もしくは複合的に添加
することにより、ＦＣＣ構造とＬ１2 構造との２つの結
晶を有する高い耐用温度の高温強度特性と優れた耐酸化
特性の高融点超合金とすることができる。In the present invention, as described above, iridium, rhodium or a mixture thereof is added to niobium, tantalum, hafnium, zirconium, uranium, vanadium,
To obtain a high melting point superalloy having two crystals of an FCC structure and an L1 2 structure and having high service temperature high temperature strength characteristics and excellent oxidation resistance characteristics by adding titanium or aluminum alone or in combination. You can
【０００８】この発明の高融点超合金の高温強度は、２
つの結晶がお互いに整合して存在する時に、その整合界
面が転位の移動を妨げることにより最大となる。イリジ
ウムに添加される元素の単独、あるいは複合的な添加量
が２原子％以下で得られる合金はＦＣＣ構造の結晶のみ
の単相組織となりやすく、また、添加量が２２原子％を
超えると得られる合金はＬ１2 構造の結晶のみの単相結
晶となりやすい。このため十分な高温強度を得ることが
できにくい。従って、元素の添加量は２原子％以上２２
原子％以下とすることが好ましい。The high temperature superalloy of the present invention has a high temperature strength of 2
When two crystals are in alignment with each other, the alignment interface is maximized by hindering dislocation movement. An alloy obtained by adding an element added to iridium alone or in a composite amount of 2 atomic% or less is likely to have a single-phase structure with only FCC structure crystals, and is obtained when the added amount exceeds 22 atomic%. The alloy is likely to be a single-phase crystal having only L1 2 structure crystals. Therefore, it is difficult to obtain sufficient high temperature strength. Therefore, the addition amount of the element is 2 atomic% or more 22
It is preferably at most atomic%.
【０００９】なお、ＦＣＣ構造とＬｌ2 構造の２相から
なる本発明合金の結晶構造を実質的に保つ範囲内で、他
の合金元素を添加して、特性をさらに向上させてもよ
い。たとえば、耐熱鋼やＮｉ基超耐熱合金などの耐熱材
料に通常添加され、高温強度向上に有効であることが広
く知られているモリブデン、タングステン、レニウムな
どの強化元素を単独にあるいは複合的に添加してもよ
い。イリジウムまたはロジウムの一部をルテニウム、パ
ラジウム、プラチナ、オスミウムなどにて置換すること
も高温強度向上に有効である。また、合金の融点を若干
下げるが、イリジウムまたはロジウムの全部をパラジウ
ムまたはプラチナで置換することも可能である。Incidentally, other alloying elements may be added within the range of substantially maintaining the crystal structure of the alloy of the present invention having two phases of FCC structure and Ll 2 structure to further improve the characteristics. For example, strengthening elements such as molybdenum, tungsten, and rhenium, which are commonly added to heat-resistant materials such as heat-resistant steel and Ni-base superalloys and are widely known to be effective in improving high-temperature strength, are added individually or in combination. You may. Substituting a part of iridium or rhodium with ruthenium, palladium, platinum, osmium, etc. is also effective for improving high temperature strength. It is also possible to replace all of the iridium or rhodium with palladium or platinum, while slightly lowering the melting point of the alloy.
【００１０】耐酸化性と耐高温腐食性の向上を目的とし
て、クロム、レニウムなど耐熱合金の耐酸化性や耐高温
腐食性の向上に一般に効果のある元素を単独もしくは複
合的に添加してもよい。また、耐熱鋼やＮｉ基超耐熱合
金に通常添加され、多結晶材として用いる場合の粒界強
度向上に有効であることが広く知られている炭素、ホウ
素などを単独にあるいは複合的に添加してもよい。For the purpose of improving oxidation resistance and high temperature corrosion resistance, elements generally effective for improving the oxidation resistance and high temperature corrosion resistance of heat-resistant alloys such as chromium and rhenium may be added alone or in combination. Good. In addition, carbon, boron, etc., which are commonly added to heat-resistant steels and Ni-base superalloys and widely known to be effective for improving the grain boundary strength when used as a polycrystalline material, are added individually or in combination. May be.
【００１１】さらに、イリジウムの一部をニッケル、コ
バルトなど廉価で比重の小さい金属元素で置換し、合金
の価格や比重を低減することもできる。さらに、Ｎｉ基
超耐熱合金の強度向上の目的で行われている一方向凝固
法や単結晶凝固法、あるいは粉末冶金成形法を適用して
組織制御を行ってもよい。２相合金に通常適用される溶
体化処理やその後の時効処理などの熱処理や、加工熱処
理などを施して、ミクロ組織を制御して特性向上を図る
ことができる。Further, a part of iridium can be replaced with a metal element such as nickel or cobalt which is inexpensive and has a low specific gravity to reduce the price and specific gravity of the alloy. Further, the structure may be controlled by applying the unidirectional solidification method, the single crystal solidification method, or the powder metallurgical molding method, which is performed for the purpose of improving the strength of the Ni-base superalloy. A heat treatment such as a solution treatment or an aging treatment that is usually applied to a two-phase alloy, a work heat treatment, or the like can be performed to control the microstructure and improve the characteristics.
【００１２】いずれにしても、イリジウム、ロジウムま
たはこれらの混合物をベースとし実質的にＦＣＣ構造と
Ｌｌ2 構造の２相からなるこの発明の合金が新しい合金
系の基本となる可能性がある。以下、実施例を示し、さ
らに詳しくこの発明の構成と作用効果について説明す
る。もちろんこの発明は以下の例によって限定されるも
のではない。In any case, the alloy of the present invention based on iridium, rhodium or a mixture thereof and consisting essentially of two phases of FCC structure and Ll 2 structure may be the basis of a new alloy system. Examples will be shown below, and the configuration and operational effects of the present invention will be described in more detail. Of course, the present invention is not limited to the following examples.
【００１３】[0013]
【実施例】イリジウムに、ニオブ、チタン、及びアルミ
ニウムを、また、ロジウムにニオブおよびタンタルをそ
れぞれ単独で１５原子％添加し、アーク溶解法により合
金を生成する。これにより生成された５種類の合金を、
耐熱強度特性について、従来のＮｉ基超合金であるＭａ
ｒＭ２４７と比較する。また、耐酸化特性について、Ｍ
ａｒＭ２４７、純イリジウム、ニオブ合金、タンタル合
金、モリブデン合金、タングステン合金と比較する。耐
熱強度特性については、１２００℃および１８００℃に
おいて圧縮試験を行った。図１は、圧縮歪みと応力との
関係を示した図である。この図１から明らかなように、
この発明のイリジウムまたはロジムウをベースとした高
融点超合金は、外部からの変形に対して非常に高い応力
（縦軸ＭＰａ）を示し、よって、従来のＮｉ基超合金に
比べて非常に優れた強度特性を有することがわかる。ま
た、耐酸化特性については、１５００℃における１時間
の酸化消耗量を計測した。表１は、各合金の酸化消耗量
と１２００℃における０．２％耐力（ＭＰａ）とを示し
たものである。この表１から明らかなように、この発明
の高融点超合金は、従来のＭａｒＭ２４７、純イリジウ
ム、ニオブ合金、タンタル合金、モリブデン合金、タン
グステン合金に比べ、同等のまたはより優れた強度を有
しながら非常に優れた耐酸化特性をも有することがわか
る。EXAMPLE Niobium, titanium, and aluminum were added to iridium, and niobium and tantalum were added to rhodium individually at 15 atom%, and an alloy was produced by an arc melting method. The five kinds of alloys produced by this are
Regarding the heat resistance property, Ma, which is a conventional Ni-based superalloy
Compare with rM247. Regarding the oxidation resistance, M
Compare with arM247, pure iridium, niobium alloy, tantalum alloy, molybdenum alloy, and tungsten alloy. Regarding the heat resistance strength characteristics, a compression test was performed at 1200 ° C and 1800 ° C. FIG. 1 is a diagram showing the relationship between compressive strain and stress. As is clear from FIG. 1,
The high melting point superalloy based on iridium or rhodium according to the present invention exhibits a very high stress (vertical axis MPa) against external deformation, and thus is extremely superior to the conventional Ni-based superalloy. It can be seen that it has strength characteristics. As for the oxidation resistance, the amount of oxidation consumption at 1500 ° C. for 1 hour was measured. Table 1 shows the oxidative consumption of each alloy and the 0.2% proof stress (MPa) at 1200 ° C. As is clear from Table 1, the high melting point superalloy of the present invention has the same or superior strength as the conventional MarM247, pure iridium, niobium alloy, tantalum alloy, molybdenum alloy, and tungsten alloy. It can be seen that it also has very good oxidation resistance.
【００１４】[0014]
【表１】 [Table 1]
【００１５】[0015]
【発明の効果】この発明は、以上詳しく説明した通り、
高い耐用温度の高温強度特性と優れた耐酸化特性を有す
る高融点超合金を製造することができる。As described in detail above, the present invention has the following advantages.
It is possible to produce a high melting point superalloy having high-temperature strength characteristics of high service temperature and excellent oxidation resistance characteristics.
【図１】この発明の高融点超合金と従来の超合金の歪み
−応力曲線を示した図である。FIG. 1 is a diagram showing strain-stress curves of a high melting point superalloy of the present invention and a conventional superalloy.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 丸子 智弘 茨城県つくば市千現１丁目２番１号 科学 技術庁金属材料技術研究所内 (72)発明者 中沢 静夫 茨城県つくば市千現１丁目２番１号 科学 技術庁金属材料技術研究所内 (72)発明者 村上 秀之 茨城県つくば市千現１丁目２番１号 科学 技術庁金属材料技術研究所内 (72)発明者 原田 広史 茨城県つくば市千現１丁目２番１号 科学 技術庁金属材料技術研究所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomohiro Maruko 1-2-1, Sengen, Tsukuba-shi, Ibaraki Inside the Institute for Materials Research, Metal Science and Technology Agency (72) Shizuo Nakazawa 1-2-1, Sengen, Tsukuba-shi, Ibaraki Prefecture Issue Inside the Institute for Metals Technology, Agency for Science and Technology (72) Hideyuki Murakami 1-2-1, Sengen, Tsukuba City, Ibaraki Prefecture Inside Institute for Institute for Materials Materials, Science and Technology Agency (72) Hiroshi Harada 1-2, Sengen, Tsukuba, Ibaraki No. 1 within the Research Institute for Metals, Science and Technology Agency
Claims (2)
合物に、ニオブ、タンタル、ハフニウム、ジルコニウ
ム、ウラン、バナジウム、チタンおよびアルミニウムの
１種または２種以上の元素が添加された合金であって、
ＦＣＣ構造とＬ１2 構造との２つの結晶構造を有するこ
とを特徴とする高融点超合金。1. An alloy in which one or more elements of niobium, tantalum, hafnium, zirconium, uranium, vanadium, titanium and aluminum are added to iridium, rhodium or a mixture thereof,
A high melting point superalloy having two crystal structures, an FCC structure and an L1 2 structure.
ニウム、ウラン、バナジウム、チタンおよびアルミニウ
ムの１種または２種以上の元素の添加量が２原子％以上
２２原子％以下である請求項１の高融点超合金。2. The refractory material having a high melting point according to claim 1, wherein the addition amount of one or more elements of niobium, tantalum, hafnium, zirconium, uranium, vanadium, titanium and aluminum is 2 atomic% or more and 22 atomic% or less. alloy.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP28613595A JP3146341B2 (en) | 1995-03-15 | 1995-11-02 | High melting point superalloy |
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7-55688 | 1995-03-15 | ||
| JP5568895 | 1995-03-15 | ||
| JP28613595A JP3146341B2 (en) | 1995-03-15 | 1995-11-02 | High melting point superalloy |
| US08/616,198 US6071470A (en) | 1995-03-15 | 1996-03-15 | Refractory superalloys |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08311584A true JPH08311584A (en) | 1996-11-26 |
| JP3146341B2 JP3146341B2 (en) | 2001-03-12 |
Family
ID=27295671
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP28613595A Expired - Lifetime JP3146341B2 (en) | 1995-03-15 | 1995-11-02 | High melting point superalloy |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3146341B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0992614A1 (en) * | 1998-10-02 | 2000-04-12 | Asea Brown Boveri AG | Coatings for turbine components |
| JP2005179782A (en) * | 2003-12-23 | 2005-07-07 | General Electric Co <Ge> | High temperature alloy, and article made and repaired therewith |
| WO2006011591A1 (en) * | 2004-07-29 | 2006-02-02 | Ngk Insulators, Ltd. | Lightweight heat resistant material for power generation gas turbine |
| WO2007091576A1 (en) * | 2006-02-09 | 2007-08-16 | Japan Science And Technology Agency | Iridium-based alloy with high heat resistance and high strength and process for producing the same |
| JP2008248322A (en) * | 2007-03-30 | 2008-10-16 | Ishifuku Metal Ind Co Ltd | HEAT RESISTANT Ir BASE ALLOY |
| WO2013065340A1 (en) * | 2011-11-04 | 2013-05-10 | 田中貴金属工業株式会社 | HIGHLY HEAT-RESISTANT HIGH-STRENGTH Rh-BASED ALLOY AND METHOD FOR PRODUCING SAME |
Citations (2)
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|---|---|---|---|---|
| JPS5388684A (en) * | 1976-12-08 | 1978-08-04 | Johnson Matthey Co Ltd | Oxidation and reduction catalyst |
| JPH01119595A (en) * | 1987-11-02 | 1989-05-11 | Tanaka Kikinzoku Kogyo Kk | Material for single crystal growing crucible |
-
1995
- 1995-11-02 JP JP28613595A patent/JP3146341B2/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5388684A (en) * | 1976-12-08 | 1978-08-04 | Johnson Matthey Co Ltd | Oxidation and reduction catalyst |
| JPH01119595A (en) * | 1987-11-02 | 1989-05-11 | Tanaka Kikinzoku Kogyo Kk | Material for single crystal growing crucible |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0992614A1 (en) * | 1998-10-02 | 2000-04-12 | Asea Brown Boveri AG | Coatings for turbine components |
| JP2005179782A (en) * | 2003-12-23 | 2005-07-07 | General Electric Co <Ge> | High temperature alloy, and article made and repaired therewith |
| WO2006011591A1 (en) * | 2004-07-29 | 2006-02-02 | Ngk Insulators, Ltd. | Lightweight heat resistant material for power generation gas turbine |
| JPWO2006011591A1 (en) * | 2004-07-29 | 2008-05-01 | 日本碍子株式会社 | Lightweight heat-resistant material for power generation gas turbine |
| JP5279187B2 (en) * | 2004-07-29 | 2013-09-04 | 日本碍子株式会社 | Lightweight heat-resistant material for power generation gas turbine |
| WO2007091576A1 (en) * | 2006-02-09 | 2007-08-16 | Japan Science And Technology Agency | Iridium-based alloy with high heat resistance and high strength and process for producing the same |
| US7666352B2 (en) | 2006-02-09 | 2010-02-23 | Japan Science And Technology Agency | Iridium-based alloy with high heat resistance and high strength and process for producing the same |
| JP4833227B2 (en) * | 2006-02-09 | 2011-12-07 | 独立行政法人科学技術振興機構 | High heat resistance, high strength Ir-based alloy and manufacturing method thereof |
| JP2008248322A (en) * | 2007-03-30 | 2008-10-16 | Ishifuku Metal Ind Co Ltd | HEAT RESISTANT Ir BASE ALLOY |
| WO2013065340A1 (en) * | 2011-11-04 | 2013-05-10 | 田中貴金属工業株式会社 | HIGHLY HEAT-RESISTANT HIGH-STRENGTH Rh-BASED ALLOY AND METHOD FOR PRODUCING SAME |
| US9605334B2 (en) | 2011-11-04 | 2017-03-28 | Tanaka Kikinzoku Kogyo K.K. | Highly heat-resistant and high-strength Rh-based alloy and method for manufacturing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3146341B2 (en) | 2001-03-12 |
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