JPH06504830A - hardened valve - Google Patents
hardened valveInfo
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- JPH06504830A JPH06504830A JP4503928A JP50392892A JPH06504830A JP H06504830 A JPH06504830 A JP H06504830A JP 4503928 A JP4503928 A JP 4503928A JP 50392892 A JP50392892 A JP 50392892A JP H06504830 A JPH06504830 A JP H06504830A
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C19/00—Alloys based on nickel or cobalt
- C22C19/03—Alloys based on nickel or cobalt based on nickel
- C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
- C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
- C22C19/055—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 20% but less than 30%
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L3/00—Lift-valve, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces; Parts or accessories thereof
- F01L3/02—Selecting particular materials for valve-members or valve-seats; Valve-members or valve-seats composed of two or more materials
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B3/00—Engines characterised by air compression and subsequent fuel addition
- F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Lift Valve (AREA)
- Powder Metallurgy (AREA)
- Sliding Valves (AREA)
- Forging (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるため要約のデータは記録されません。 (57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】 硬化肉盛した弁 技術分野 本発明は、弁、特にニッケル系合金製の弁座区域を備えた可動弁部材を含む、内 燃機関用の排気弁に関する。[Detailed description of the invention] hardened valve Technical field The present invention relates to a valve, particularly an internal valve member comprising a movable valve member with a valve seat area made of a nickel-based alloy. This invention relates to an exhaust valve for a combustion engine.
内燃機関用排気弁中の弁座に使用する材料組成の選択は、問題とするエンジンの 運転の信頼性に関して、および排気弁の寿命に、したがって必要な保守作業の程 度に関して、以前から重要な問題である。The choice of material composition for the valve seat in an internal combustion engine exhaust valve depends on the engine in question. Regarding reliability of operation and the service life of the exhaust valve and therefore the amount of maintenance work required. This has been an important issue for some time.
内燃機関では、作動シリンダー内の燃焼により、硬質粒子からなるコークス化残 留物が生じ、その硬質粒子が排気弁を通って運ばれ、それらの粒子が閉鎖弁座間 に詰まり、弁座面に窪み跡を付けることがある。この様な傷跡により、最初は良 く知られている様に局所的な洩れが生じ、次いでそこを通り抜けて燃焼が起こり 、弁座面が腐食により劣化することがある。In internal combustion engines, combustion in the working cylinder produces coked residue consisting of hard particles. The hard particles are carried through the exhaust valve and the particles are deposited between the closing valve seats. may become clogged, leaving dents on the valve seat surface. Such scars may initially cause As is well known, localized leakage occurs, through which combustion occurs. , the valve seat surface may deteriorate due to corrosion.
先行技術 弁座の材料は、窪み跡の形成を少なくする、または遅らせるために十分な硬度を 有するのが望ましい。大型の重燃料油を燃焼するディーゼルエンジンでは、近年 、ニッケル系の硬化肉盛材料アロイ５ｏがら弁座区域を製造する試みがなされて いるが、この材料は、最も重要な合金成分として１２％Ｃｒ、３．９％５ｉｓ２ ．９％Ｆｅ、２．２５％Ｂおよび０．５％Ｃを含む。アロイ５０は、望ましい硬 度に加えて、重燃料油ディーゼルエンジンの排気弁がさらされる腐食性の強い環 境に対して耐高温腐食性を示す。良好な耐腐食性に加えて、使用材料の非常に高 い機械的強度が必要とされる大孔径の、例えば６００〜９００■のシリンダーを 有するエンジンでは、運転経験から、硬化肉盛材料アロイ５０に放射上の亀裂が 生じ、そのために弁座を貫通する燃焼が起こる、あるいは危険な周辺部の亀裂が 生じる場合のあることが分かっている。その様な大きさのエンジンには、損傷の 危険性を無くすために、より延性の高い硬化肉盛材料であるステライト６、すな わちコバルト系合金が使用されるが、この合金は実際の環境下でアロイ５０より も耐高温腐食性が劣り、より短期間で使用中の弁の状態を検査することになる。prior art The valve seat material should have sufficient hardness to reduce or delay the formation of pit marks. It is desirable to have one. In recent years, diesel engines that burn large amounts of heavy fuel oil have Attempts have been made to manufacture the valve seat area from nickel-based hardfacing material Alloy 5O. However, this material contains 12% Cr and 3.9% 5is2 as the most important alloying components. ．． Contains 9% Fe, 2.25% B and 0.5% C. Alloy 50 has a desirable hardness. In addition to corrosion, the exhaust valves of heavy fuel oil diesel engines are exposed to Shows high temperature corrosion resistance against environmental conditions. In addition to good corrosion resistance, the very high For example, use a cylinder with a large hole diameter of 600 to 900 mm that requires high mechanical strength. Based on operating experience, in engines with resulting in combustion through the valve seat or dangerous peripheral cracks. It is known that this can occur. Engines of such size are subject to damage. To eliminate the risk, a more ductile hardfacing material such as Stellite 6 was used. In other words, a cobalt-based alloy is used, but this alloy has a higher resistance than Alloy 50 under actual conditions. However, the high-temperature corrosion resistance is poor, and the condition of the valve in use must be inspected for a shorter period of time.
硬化肉盛材料の硬度が高温で低下することは良く知られている。ステライト６の 硬度は室温で約３７０ＨＢで、５００℃の温度では約２９８ＨＢであり、対応す る温度で、アロイ５０の硬度は約５３０ ＨＢから４２０ＨＢに低下する。It is well known that the hardness of hardfacing materials decreases at high temperatures. Stellite 6's The hardness is about 370HB at room temperature and about 298HB at a temperature of 500℃, corresponding to At this temperature, the hardness of alloy 50 decreases from approximately 530 HB to 420 HB.
また、特に今日まで知られている、硬度の高いＮｉ系の硬化肉盛材料は一般的に 延性が悪く、または無く、したがって疲労強度特性が低いことも良く知られてい る。In addition, particularly the hardened Ni-based hardfacing materials known to date are generally It is also well known that ductility is poor or absent, and therefore fatigue strength properties are low. Ru.
これまで公知のＮｉ系合金では、好ましくはＢ、ＳＬおよびＣの成分を加えるこ とにより所望の硬度を得る。In the conventionally known Ni-based alloys, it is preferable to add the components B, SL and C. to obtain the desired hardness.
特に、該合金の構造中の金属ホウ化物は、それらの大きさおよび形状により硬化 肉盛の延性を非常に悪くし、すでに溶接中に、ある′いは短い、または長い加工 サイクルの後で亀裂を生じる危険性がある。In particular, the metal borides in the structure of the alloy are hardened due to their size and shape. The ductility of the build-up becomes very poor and the process is already done during welding, or short or long machining. There is a risk of cracking after cycling.
Ｂ含有量を分析値中で低減した、あるいは完全に無くした場合、合金の硬度を高 くするために、炭化物を広範囲に析出させることによりＣ含有量を増加する必要 があるが、析出した炭化物網目構造が同様に延性を著しく低下させる。If the B content is reduced in the analytical values or completely eliminated, the hardness of the alloy will increase. In order to reduce the carbon content, it is necessary to increase the C content by precipitating carbides over a wide range However, the precipitated carbide network structure also significantly reduces ductility.
上記の先行技術によるニッケル系合金の一般的な特徴は、約５００℃の運転温度 で高い硬度を得るためには、室温において著しく高い硬度を、したがって脆性を 合金に与える必要があることである。The general characteristics of the above-mentioned prior art nickel-based alloys include an operating temperature of approximately 500°C; In order to obtain high hardness at It is necessary to give to the alloy.
ＪＰ−Ａ−５９−９１４６（公開）には、合金を溶接できる様にするためにＡＩ 含有量が４．５％未満であるニッケル合金の弁が記載されている。この合金がＴ ｉ１ＷおよびＭＯを、０．５５％を超えるＣと組み合わせて含むことにより、炭 化物の析出により合金の硬度を高くすることができる。開示されている２％まで のＢ含有量は、硬度を高（するのにさらに大きく貢献する。しかし、非常に硬い 炭化物およびホウ化物が比較的軟らかいマトリックス相中に析出するので、合金 の微小硬度に変動があり、上記の様に、炭化物の網目構造も延性を低下させる。JP-A-59-9146 (published) describes the use of AI to enable welding of alloys. Valves of nickel alloys with a content of less than 4.5% are described. This alloy is T By including i1W and MO in combination with more than 0.55% C, carbon The hardness of the alloy can be increased by the precipitation of oxides. Up to 2% disclosed B content contributes even more to high hardness. However, very hard As carbides and borides precipitate in a relatively soft matrix phase, the alloy There are variations in the microhardness of the carbide, and as mentioned above, the carbide network structure also reduces ductility.
ＵＳ−Ａ−３，７９５，５１０は２０％Ｃｒ、５．５％ＡＩ、２．５％Ｔｉ、７ ．５％Ｆｅおよび０，１５％Ｃを含むニッケル合金を記載している。弁部分（ｐ ｒｏｐｅｒ）は、予め製造したニッケル合金製の半製品を炭素鋼製の残りの弁部 分に摩擦圧接することにより製造する。この合金は一般的な方法では溶接できず 、硬度は、本発明が目指す硬度より劣っている。US-A-3,795,510 is 20% Cr, 5.5% AI, 2.5% Ti, 7 ．． A nickel alloy containing 5% Fe and 0.15% C is described. Valve part (p roper) uses a pre-manufactured nickel alloy semi-finished product to replace the remaining valve part made of carbon steel. Manufactured by friction welding. This alloy cannot be welded using conventional methods. , the hardness is inferior to the hardness aimed at by the present invention.
本発明 本発明の目的は、あらゆる大きさのエンジンに使用でき、燃焼生成物に対する良 好な耐高温腐食性ならびに５００℃までの温度で高い硬度を有し、同時に十分な 延性を有し、機械的に高い負荷のかかる、周期的に運転する弁に応用できる、硬 化肉盛材料を備えた弁を提供することである。present invention It is an object of the present invention to be able to be used in engines of all sizes and to provide a It has good high temperature corrosion resistance as well as high hardness at temperatures up to 500℃, and at the same time has sufficient A hard material that is ductile and can be applied to cyclically operated valves that are subjected to high mechanical loads. It is an object of the present invention to provide a valve equipped with an overlay material.
そこで、冒頭に述べた弁は、本発明により、ニッケル系合金が、重量％で表して 、一般的に含まれる不純物は別にして、２０〜２４％Ｃｒ１０〜８％Ｗ、４〜７ ％ＡＩ、０．２〜０．５５％０１０〜１．８％Ｈｆ、０〜１、５９６Ｎｂ、 ０ 〜８．０％Ｍｏ、０〜１．２％Ｓｔおよび０〜１５％Ｆｅを含み、Ｗ含有量およ びＭＯＣ含有量合計で１０％を超えないことを特徴とする。Therefore, in the valve mentioned at the beginning, according to the present invention, the nickel-based alloy is , apart from commonly included impurities, 20-24% Cr10-8% W, 4-7 %AI, 0.2-0.55% 010-1.8% Hf, 0-1, 596Nb, 0 ~8.0%Mo, 0~1.2%St and 0~15%Fe, W content and and MOC content does not exceed 10% in total.
ここで驚くべきことに、この種の合金は望ましい特性を有することが分かった。It has now surprisingly been found that alloys of this type have desirable properties.
以前は、この様にアルミニウム含有量の高いニッケル系合金を溶接すると、溶接 金属中に極度の熱亀裂傾向が生じると共に、多層溶接では熱の影響を受けた区域 に亀裂が形成されることが一般的に認められている。そのため文献中では、３〜 ４％を超えるＡｔを含むＮｉ−Ｃｒ合金は、溶接不可能と記載されている。Previously, when welding nickel-based alloys with high aluminum content like this, welding There is an extreme thermal cracking tendency in the metal and in multi-layer welds the heat-affected area It is generally accepted that cracks form in Therefore, in the literature, 3~ Ni-Cr alloys containing more than 4% At are described as unweldable.
上記のＡＩ含有量を有する、本発明のＮ１−Ｃｒ−ＡＩ−Ｃ合金の溶接性により 、この種の合金の析出硬化機構を利用することができ、それによって金属開祖Ｎ Ｌ ａ Ａ １ （γ°）がコヒーレント硬度増加相（ｃｏｈｅｒｅｎｔ ｈ ａｒｄｎｅｓｓ Ｉｎｃｒｅａｓｉｎｇ ｐｈａｓｅ）として延性のＮｉマトリ ックス（γ）中に析出する。γ°相は基本γ相中に４５％もの、好ましくは少な くとも２０％の構造的な量で析出し、所望の高い強度および硬度を有する材料を 得ることができ、その強度および硬度は、正常に作動している排気弁がさらされ る温度範囲を含む２０〜６００℃の温度範囲内で大体一定である。Due to the weldability of the N1-Cr-AI-C alloy of the present invention having the above AI content, , it is possible to take advantage of the precipitation hardening mechanism of this type of alloy, thereby making metal founder N L a A 1 (γ°) is the coherent hardness increasing phase (coherent h Ductile Ni matrix (increasing phase) It precipitates in the box (γ). The γ° phase accounts for as much as 45%, preferably as little as 45%, in the basic γ phase. Precipitates in a structural amount of at least 20% to produce a material with the desired high strength and hardness. Its strength and hardness can be obtained by exposing a normally working exhaust valve to It remains approximately constant within the temperature range of 20 to 600°C, including the temperature range of 20 to 600°C.
合金のＣｒ含有量は、硫黄化合物が本質的な役割を果たす実際の環境下で合金の 耐腐食性が高くなければならない、という必要条件を満たす上で非常に大きく貢 献する。ＡＩが含まれることにより、弁座上にＡ １２０ ａおよびＣｒ２Ｏ３ の組合わせ表面層が形成され、この層により耐腐食性が強化され、その耐腐食性 は７５０℃以上の温度で特に改良される。窪み跡が発生して弁座上に洩れが生じ 、その漏れが局所的に、弁の一般的な作動温度よりも著しく高い表面温度を引き 起こす様な場合に、その耐腐食性の改良により、特に弁座の急速な劣化が防止さ れる。The Cr content of the alloy is determined by It makes a huge contribution to meeting the requirement of high corrosion resistance. dedicate By including AI, A120a and Cr2O3 are formed on the valve seat. A combination of surface layers is formed, which enhances the corrosion resistance and is particularly improved at temperatures above 750°C. Leaking occurs on the valve seat due to dent marks. , the leak locally causes a surface temperature significantly higher than the general operating temperature of the valve. Its improved corrosion resistance prevents rapid deterioration of the valve seat, especially when It will be done.
さらに、Ｃｒが含まれることにより、合金の強度増加に貢献する溶体化強化作用 （ｓｏｌｕｔｌｏｎ−ｓｔｒｅｎｇｔｈｅｎｌｎｇｅｆｆｅｃｔ）が得られる。Furthermore, the inclusion of Cr has a solution strengthening effect that contributes to increasing the strength of the alloy. (solutlon-strength effect) is obtained.
この溶体化強化作用は、相互に交換できるＭＯおよびＷを加えることにより、さ らに促進することができる。ＷおよびＭＯの総合有量は、合金の炭化物の形態が 悪影響を受けるので、１０％を超えてはならない。This solution strengthening effect can be enhanced by adding mutually exchangeable MO and W. can be further promoted. The total amount of W and MO depends on the carbide form of the alloy. It should not exceed 10% as it will have negative effects.
合金の硬度は、Ｃ含有量を調整し、それによって炭化物析出の量および形態に影 響を及ぼすことにより最終的に決定される。Ｃ含有量が０．２％未満である場合 、所望の硬度は得られず、Ｃ含有量が０．５５％を超えると、望ましい延性を得 るのが困難になる。０．３〜０．５５％の範囲のＣを含む合金が、弁材材として 使用するのに有利な硬度および延性の組合わせを有することが分かった。The hardness of the alloy adjusts the C content and thereby influences the amount and morphology of carbide precipitation. The final decision is made based on the influence of the When the C content is less than 0.2% , the desired hardness cannot be obtained, and when the C content exceeds 0.55%, the desired ductility cannot be obtained. It becomes difficult to An alloy containing C in the range of 0.3 to 0.55% is used as valve material. It has been found to have an advantageous combination of hardness and ductility for use.
市販のＮｉ、Ｃｒ、ＢおよびＳｔ硬化肉盛合金と対照的に、本発明の合金は、高 温静水圧（ＨＩ Ｐ）混合物の排気弁製造にも使用できるが、これは、合金の固 相温度（ｓｏｌｉｄｕｓ ｔｅｍｐｅｒａｔｕｒｅ）が弁の基礎材料の固相温度 に近いためであり、これがＨＩＰ製法を使用するための前提条件である 合金の延性は、炭化物の形態により大きく影響され、特に針状およびフレーク状 炭化物析出物は延性に好ましくない影響を与える。実際の合金に関しては、「中 国文字」と呼ばれる種類の不利な炭化物形態を形成する傾向は、Ｃ含有量と共に 段階的に増加することが確認されており、この理由からＣ含有量は０．６％を超 えるべきではない。In contrast to commercially available Ni, Cr, B and St hardfacing alloys, the alloy of the present invention has a high It can also be used to make exhaust valves for hot isostatic (HIP) mixtures, but this is due to the hardness of the alloy. The solidus temperature is the solidus temperature of the valve's base material. This is because it is close to , and this is a prerequisite for using the HIP method. The ductility of the alloy is greatly influenced by the morphology of the carbides, especially needle-like and flake-like Carbide precipitates have an unfavorable effect on ductility. Regarding the actual alloy, please refer to The tendency to form unfavorable carbide forms of the type called "national characters" increases with the C content. It has been confirmed that the C content increases gradually, and for this reason the C content exceeds 0.6%. It shouldn't be.
炭化物形態は、Ｉｆを１〜２％の量で加えることにより好ましい影響を受けるこ とが分かっている。Ｈｆの添加により、炭化物の形態はフレーク状および針状か ら、合金の延性を低下させる傾向の少ない、より丸い形状に変化する。しかし、 予期せぬことに、炭素含有量が５％を超える場合、炭化物の析出はＨｆの添加に より僅かに影響されるだけであり、したがってこの場合、Ｃ含有量を０，３５〜 ０，５０％に調節できるので好都合である。The carbide morphology can be favorably influenced by adding If in amounts of 1-2%. I know that. Due to the addition of Hf, the morphology of the carbide changes from flaky to acicular. It changes to a more rounded shape, which has less tendency to reduce the ductility of the alloy. but, Unexpectedly, when the carbon content exceeds 5%, carbide precipitation increases with the addition of Hf. and therefore in this case the C content from 0.35 to It is convenient because it can be adjusted to 0.50%.
その上驚くべきことに、Ｎｂを１．５％以下の量で加えた場合、合金の構造は、 特にゆっくりと凝固しつつある溶融物に関して、硬度を高くすることが確認され たが、これは恐ら＜Ｎｂが炭化物析出物の量を増加させる、および／または炭化 物組成を変えるためであろう。同時に、合金にＮｌ）を加えることにより、形態 の変わった炭化物が微分散した金属炭化物の形で生じることが確認されたが、こ れが合金の延性に好ましい影響を及はすと考えられる。Moreover, surprisingly, when Nb is added in amounts below 1.5%, the structure of the alloy is It has been found to increase hardness, especially for slowly solidifying melts. However, this is probably due to <Nb increasing the amount of carbide precipitates and/or This is probably to change the composition of the material. At the same time, by adding Nl) to the alloy, the morphology It was confirmed that unusual carbides occur in the form of finely dispersed metal carbides, but this It is thought that this has a favorable influence on the ductility of the alloy.
弁座区域を溶接により取り付ける場合、合金にＳｔを添加し、ケイ素の脱酸効果 により溶接特性を改良することができる。Ｓｉ含有量は０．８〜１．２％に固定 するのが好適である。しかし、驚くべきことに、該Ｓｉ含有量は、Ａ１含有量が ５〜５．５％を超える場合に、ＡＩ。When attaching the valve seat area by welding, St is added to the alloy to improve the deoxidation effect of silicon. The welding properties can be improved by this. Si content is fixed at 0.8-1.2% It is preferable to do so. However, surprisingly, the Si content is lower than the A1 content. AI if more than 5-5.5%.
Ｓｉ、Ｃｒおよび恐らくＣの濃度の高い共晶（ｅｕｔｅｃｔｉｃｕｍ）の形成を 引き起こすことが分かった。該共晶は、合金の残りの構造的元素よりも耐腐食性 が本質的に低いことが分かったので、該共晶相の量を約５％以下に制限するのが 望ましい。Formation of a eutectic with high concentrations of Si, Cr and possibly C I found out that it causes The eutectic is more corrosion resistant than the remaining structural elements of the alloy. Since it was found that the amount of the eutectic phase is essentially low, it is recommended to limit the amount of the eutectic phase to about 5% or less. desirable.
弁座区域を支持する弁部材は、一般的にオーステナイト系ステンレス鋼合金から 形成されている。弁座区域を溶接により取り付ける場合、鋼合金がニッケル系充 填材料に僅かに混入し、それによって、特に第一の取り付は溶接層において、１ ５９６を超えない量のＦｅが加えられる。The valve member supporting the valve seat area is typically made from an austenitic stainless steel alloy. It is formed. If the valve seat area is attached by welding, the steel alloy may be nickel-filled. slight contamination with the filler material, whereby the first installation in particular in the weld layer An amount of Fe not exceeding 596 is added.
２０％を超えない量のＦｅは、γ相に強化作用を及ぼすことができるが、同時に 耐腐食性は低下する。５％のＦｅ含有量ですでに、劣化した腐食特性の危険性が あり、したがって、最終的に溶接された層または弁座区域の表面に近い所におけ るＦｅ含有量は１０％を超えない、好ましくは５％未満にすべきである。Fe in amounts not exceeding 20% can exert a strengthening effect on the γ phase, but at the same time Corrosion resistance decreases. Already with a Fe content of 5% there is a risk of degraded corrosion properties. Yes, and therefore close to the surface of the final welded layer or valve seat area. The Fe content should not exceed 10%, preferably less than 5%.
Ｎｉ含有量が低いと析出硬化が低減し、合金の硬度が下がることがあるので、弁 の表面に近い区域では、合金は少なくとも５５％のＮｉを含むのが有利である。Low Ni content can reduce precipitation hardening and reduce the hardness of the alloy, so valve Advantageously, in the area close to the surface of the alloy, the alloy contains at least 55% Ni.
上に述べた様に、合金の硬度は、合金の高ＡＩ含有量がＮｉ系材料自体（Ｎｉマ トリックス）の硬度を増加させ、その硬度が高温で維持される析出硬化、および 基礎材料部分中の炭化物の析出の組合わせにより得られる。As mentioned above, the hardness of the alloy is determined by the high AI content of the alloy. precipitation hardening, which increases the hardness of the trix) and maintains that hardness at high temperatures; Obtained by a combination of carbide precipitation in the base material parts.
好ましい炭化物形態を維持するために、合金は、上記のＣ含有量に加えて、ある 最小量の炭化物形成剤を含むべきである。したがって、Ｈｆ５Ｎｂ、ＷおよびＭ ｏの含有量は少なくとも５％になるのが有利である。In order to maintain the preferred carbide morphology, the alloy, in addition to the above C content, has a It should contain a minimum amount of carbide formers. Therefore, Hf5Nb, W and M Advantageously, the content of o is at least 5%.
ここで本発明の様々な実施例を、一部図面を参照しながら詳細に説明するが、図 １〜４は、本発明の４種類の異なった合金を研削し、研磨した試料の、３２０倍 に拡大した写真を示す。Various embodiments of the present invention will now be described in detail with reference to some drawings. 1 to 4 are 320 times higher than the samples obtained by grinding and polishing four different alloys of the present invention. Shows an enlarged photo.
本発明の合金と以前から公知の弁座用合金を比較するための基準を得るために、 オーステナイト系ステンレス鋼製の、直径Ｄ＝２５０＋ｕ＋の弁頭の形の、幾何 学的形状が同一な４個の弁棒半製品を製造した。これらの棒部材を予熱した後、 それぞれの半製品に４種類の異なった合金を、移動アークを有するプラズマ溶接 および下記の溶接パラメータにより溶接した。In order to obtain a basis for comparing the alloy of the present invention with previously known valve seat alloys, Geometry in the form of a valve head of diameter D=250+u+ made of austenitic stainless steel Four valve stem semi-finished products with the same scientific shape were manufactured. After preheating these bar members, Plasma welding with moving arc of four different alloys into each semi-finished product and welded using the following welding parameters.
溶接粉末の粒子径 ５０〜１５０μ棗 溶着率 １．７ｋｇ／時間 溶接電流 １２０Ａ 溶接速度 約６０ ｓｍ／時間 溶接継ぎ目は３層により形成し、深さ８■、幅２５■で、継ぎ目の側方角度を６ ０°にした。Particle size of welding powder: 50-150μ Welding rate 1.7kg/hour Welding current 120A Welding speed: approx. 60 sm/hour The welded seam is made of three layers, with a depth of 8cm, a width of 25cm, and a lateral angle of 6cm. It was set to 0°.
製造した合金の分析結果を、表１に示す。表１において、ステライト６およびア ロイ５０は上述した合金であり、ＢＷＩ−５０の合金も同様に市販のニッケル合 金であり、Ｉ−１が本発明の合金である。Table 1 shows the analysis results of the manufactured alloy. In Table 1, Stellite 6 and A Roy 50 is the alloy mentioned above, and BWI-50 alloy is also a commercially available nickel alloy. gold, and I-1 is the alloy of the present invention.
表１ 溶接後、溶接継ぎ目表面を裏返し、キャピラー試験により欠陥を検査した。Table 1 After welding, the weld seam surface was turned over and inspected for defects by capillary testing.
次にブランクを炉中に入れ、２５０℃に加熱し、続いて水浴中、約４０℃の温度 で急冷した。ブランクを目視およびキャピラー試験で検査したところ、これらの 弁座材料に亀裂は発見されなかった。The blank is then placed in an oven and heated to 250 °C, followed by a water bath at a temperature of approximately 40 °C. It was rapidly cooled. Visual and capillary inspection of the blanks revealed that these No cracks were found in the valve seat material.
すべてのブランクを再度炉に戻して３５０℃に加熱し、続いてまず温度約７０℃ の水浴中で急冷し、次いで目視およびキャピラー試験で検査したところ、アロイ ５０に３箇所の放射状亀裂および幾つかの細かいひびが発見されたが、残りの３ 個に欠陥は無かった。All blanks were returned to the furnace again and heated to 350°C, followed by a first temperature of approx. 70°C. The alloy was quenched in a water bath and then inspected visually and by capillary test. Three radial cracks and some fine cracks were found in 50; There were no defects in the pieces.
３個の完全な試料を４５０℃に加熱し、温度衝撃試験を繰り返した。約７０℃の 水中で急冷した後、ＢＷＩ−５０に粗い網目状のひびが見られたが、残りの２個 は弁座区域に損傷は無かった。Three complete samples were heated to 450°C and the temperature shock test was repeated. Approximately 70℃ After quenching in water, coarse mesh cracks were observed on BWI-50, but the remaining two There was no damage to the valve seat area.
次いで、これらの２個を５２０℃に加熱し、約７０℃の水中で急冷し、続いて目 視およびキャピラー試験で検査したところ、ステライト６合金には多数の放射状 の小亀裂が見られ、Ｉ−１合金には弁座区域に放射状亀裂が１個発見された。残 りの３種類の合金における亀裂と反対に、Ｉ−１における亀裂は、亀裂の縁部が 丸くなった形の塑性変形の徴候が見・られた。These two pieces were then heated to 520°C, rapidly cooled in water at about 70°C, and then When examined by visual and capillary tests, the Stellite 6 alloy contains numerous radial Small cracks were observed in the I-1 alloy, and one radial crack was found in the valve seat area. Residue In contrast to the cracks in the three alloys, the crack in I-1 shows that the edges of the crack Signs of plastic deformation in a rounded shape were observed.
本発明のニッケル系合金は、驚くほど良好な溶接性、および完全にステライト６ に匹敵し、ニッケル合金のアロイ５０およびＢＷＩ−５０より著しく良い延性お よび耐亀裂性を示す。The nickel-based alloy of the present invention has surprisingly good weldability and is completely stellite 6 ductility and significantly better than the nickel alloys Alloy 50 and BWI-50. and crack resistance.
各弁棒片の弁座区域から放射状部分を切り取り、それらの部分に対して室温で、 弁座表面から様々な距離で、溶接のほぼ中央で硬度試験（ＨＶ２０）を行なった 。その結果を、表２に示す。Cut a radial section from the valve seat area of each valve stem piece and apply the Hardness tests (HV20) were conducted at various distances from the valve seat surface and approximately in the center of the weld. . The results are shown in Table 2.
表２ ニッケル系合金の硬度は、弁棒材料の弁座材料中への混入に敏感であり、溶融物 は急速に凝固し、そのために合金の組成の完全な均質化が妨げられるために、弁 座材料の外側半分の硬度は、予想される限界内で変動するものと思われる。Table 2 The hardness of nickel-based alloys is sensitive to the mixing of the valve stem material into the valve seat material, and The valve solidifies rapidly, which prevents complete homogenization of the alloy composition. The hardness of the outer half of the seat material is expected to vary within expected limits.
実施例２ 高温における合金の硬度を試験するために、いわゆるＨＩＰ製法（高温静水圧圧 縮）により粉末原料から、直径３ｃｌｖおよび長さ１６０ｓ＋ｓの棒状ブランク を製造し、そこから約８１厚の試験片を切り取り、硬度測定に使用した。これら の半製品は合金ステライト６および表１の１−１に相当する分析値を有するニッ ケル系合金で製造した。測定した硬度（ＨＢ１０／３０００／１５）を、表３に 示す。５００℃における高温硬度は、ステライトの場合に著しく低下する（２８ ％）が、本発明の合金の硬度はほんの僅か（３％）しか低下しないことが分かる 。Example 2 In order to test the hardness of alloys at high temperatures, the so-called HIP method (high temperature isostatic pressure A rod-shaped blank with a diameter of 3clv and a length of 160s+s is produced from powder raw material by A test piece with a thickness of approximately 81 cm was cut from the test piece and used for hardness measurement. these The semi-finished product is alloy stellite 6 and nickel having an analysis value corresponding to 1-1 in Table 1. Manufactured from Kel-based alloy. The measured hardness (HB10/3000/15) is shown in Table 3. show. The high-temperature hardness at 500°C is significantly reduced in the case of stellite (28 %), it can be seen that the hardness of the inventive alloy decreases only slightly (3%). .
表３ 硬度を表２の硬度と比較するために、ステライト６およびＩ−１の３個の試験片 の硬度測定（ＨＶ２０）を室温で行なったが、その結果を表４に示す。Table 3 In order to compare the hardness with the hardness in Table 2, three specimens of Stellite 6 and I-1 were The hardness measurement (HV20) was carried out at room temperature, and the results are shown in Table 4.
表４ 表２に示す約２０℃で測定したアロイ５０弁座材料の硬度４７３ＨＶは、その弁 座材料の加工温度では約２０％低下して３７８ＨＶになるのに対し、Ｉ−１合金 の硬度は作動温度で約４１３ＨＶになり、僅か３％しか低下し手作業のＴＩＧ溶 接により、本発明の異なった合金を、直径８０ｍｍで、厚さ２０■のオーステナ イト系ステンレス鋼製弁のブランクに溶接した。合金のだいたいの分析値を、表 ５に示す。Table 4 The hardness of the Alloy 50 valve seat material measured at about 20°C shown in Table 2 is 473HV. The processing temperature of the seat material decreases by about 20% to 378HV, whereas the I-1 alloy The hardness is approximately 413 HV at the operating temperature, which is only 3% lower than manual TIG melting. By contact, different alloys of the present invention are made into an austener with a diameter of 80 mm and a thickness of 20 mm. Welded to the blank of a stainless steel valve. The approximate analysis values of the alloy are shown in the table. 5.
各合金の２０℃および約５００℃における硬度測定（ＨＢ］、０／３０００／１ ５）を行なった。その結果を表５に示す。Hardness measurement (HB) of each alloy at 20°C and approximately 500°C, 0/3000/1 5) was performed. The results are shown in Table 5.
表５ 室温から約５００℃に加熱した時の硬度低下は、合金１−２で約２％、合金！− ５で約７％であることが分かる。Table 5 When heated from room temperature to approximately 500°C, the hardness decreases by approximately 2% for Alloy 1-2, and Alloy! − 5, it is about 7%.
さらに、各合金の研削し、研磨した試料を調製したが、図１〜４は、合金１−２ 〜Ｉ−５の試料の写真を示す。Furthermore, ground and polished samples of each alloy were prepared, and Figures 1 to 4 show alloy 1-2. - Photographs of samples of I-5 are shown.
図１で、合金１−２中に、恐ら（ＡＩＳＳｔＳＣｒおよびＣを含む共晶ペロブス カイトからなる球状の黒い析出物と共に、アルミニウムを含まない金属炭化物の 細長い軽い析出物が見られる。延性がより高い合金は、炭化物析出物を少なくす ることにより得られる。In Figure 1, alloy 1-2 contains a eutectic perovs containing (AISStSCr and C). Aluminum-free metal carbides with spherical black precipitates consisting of kites. Elongated light precipitates are visible. More ductile alloys produce fewer carbide precipitates. It can be obtained by
図２の合金Ｉ−３は、セルを有し、その中で物質が一様に結晶格子配向している 、明らかなデンドライト構造を示している。デンドライトアームの間に、幾つか のペロブスカイトの析出物および金属炭化物の析出物がある。Alloy I-3 in Figure 2 has cells in which the material is uniformly oriented in the crystal lattice. , showing an obvious dendrite structure. Some between the dendrite arms There are perovskite precipitates and metal carbide precipitates.
この合金は、恐らく良好な延性と共に高い高温硬度を有する。This alloy probably has high hot hardness along with good ductility.
図３の合金１−４は、やや不均一なデンドライト構造を有し、極めて少ないペロ ブスカイトの析出物を示している。図４の合金１−５ではペロブスカイトの析出 物がほとんど消失している。Alloys 1-4 in Figure 3 have a slightly non-uniform dendrite structure and very few pelants. Showing buskite precipitates. In alloy 1-5 in Figure 4, perovskite precipitation Almost everything has disappeared.
実施例４ 表１および３におけるＩ−１に対応する分析値を有するニッケル系合金に、実施 例２に記載する試験に対応する硬度試験を行なったが、硬度測定の前にブランク について、溶体化処理を１１５０℃の温度で２時間行ない、続いて析出硬化を７ ５０℃の温度で少なくとも２時間行なう熱処理に行った。測定した硬度（ＨＢＩ Ｏ／３０００／１５）を表６に、また硬度（ＨＶ２０）を表７に示す。Example 4 The test was carried out on nickel-based alloys with analysis values corresponding to I-1 in Tables 1 and 3. A hardness test corresponding to the test described in Example 2 was carried out, but before the hardness measurement a blank Solution treatment was carried out at a temperature of 1150°C for 2 hours, followed by precipitation hardening for 7 hours. A heat treatment was carried out at a temperature of 50° C. for at least 2 hours. Measured hardness (HBI Table 6 shows the hardness (HV20) and Table 7 shows the hardness (HV20).
表６ 表７ 高温硬度は僅かな低下（７％）を示すが、５００℃で得られる約４６０ＨＢの硬 度は、先行技術の硬化肉盛合金により得られる硬度よりも著しく高い。Table 6 Table 7 Although the high temperature hardness shows a slight decrease (7%), the hardness of about 460HB obtained at 500℃ The hardness is significantly higher than that obtained with prior art hardfacing alloys.
合金のＣｒ含有量が２０％未満になると、高温における耐腐食性が悪くなり、Ｃ ｒ含有量が２４％を超えると、合金の強度特性が不利な影響を受け、さらに溶接 性も悪くなる。If the Cr content of the alloy is less than 20%, the corrosion resistance at high temperatures will deteriorate, and the Cr content will deteriorate. When the r content exceeds 24%, the strength properties of the alloy are adversely affected, and even welding Sex also gets worse.
ＡＩ含有量が４％未満では、高温硬度が低くなり過ぎ、ＡＩ含有量が７％を超え るとペロブスカイト析出物が合金の耐腐食性および延性に悪影響を与えると考え られる。If the AI content is less than 4%, the high temperature hardness will be too low, and if the AI content exceeds 7%. It is believed that perovskite precipitates have a negative effect on the corrosion resistance and ductility of the alloy. It will be done.
この合金は、弁座区域を弁部材上に溶接するのに使用でき（この場合、合金はＳ ｔを含み、容易に酸化するＹの含有量をできるだけ低くすべきであり）、あるい はＨＩＰ法による弁部材の製造にも使用できる。This alloy can be used to weld the valve seat area onto the valve member (in this case the alloy is S The content of Y, which contains t and is easily oxidized, should be as low as possible), or can also be used to manufacture valve members by the HIP method.
２０〜２３％Ｃｒ、４〜５．５％ＡＩＯ〜１３％Ｆｅ。20-23% Cr, 4-5.5% AIO-13% Fe.
０．３〜０．５％Ｃおよび５〜７．５％Ｗおよび／またはＭＯを含むニッケル合 金は高硬度ならびに良好な延性を有し、弁座区域を溶接により取り付ける場合、 これは２０〜２３％Ｃ「、４〜５．５％ＡＩ、０．３〜０．５％Ｃ，０，８〜１ ．２％Ｓｉおよび５〜７．５％Ｗおよび／またはＭＯを含むニッケル系の充填材 を加えることにより効果的に行なうことができる。Nickel alloy containing 0.3-0.5% C and 5-7.5% W and/or MO Gold has high hardness as well as good ductility and is suitable for attaching the valve seat area by welding. This is 20-23% C'', 4-5.5% AI, 0.3-0.5% C, 0,8-1 ．． Nickel-based filler containing 2% Si and 5-7.5% W and/or MO This can be done effectively by adding .
２２．５〜２３．５％Ｃ「、４６０〜５．０％ＡＩ。22.5-23.5% C'', 460-5.0% AI.
０．４０〜０．４５％Ｃ，１，０〜１，５％Ｈｆおよび５．５〜６％Ｗおよび／ またはＭｏを含む合金は、耐亀裂性が非常に高く要求される場合に使用できる。0.40-0.45% C, 1,0-1,5% Hf and 5.5-6% W and/ Alternatively, alloys containing Mo can be used when very high crack resistance is required.
合金をＨＩＰ法で製造する場合、分析にＹを含むことにより、高温耐性に好影響 を与えることができる。When producing alloys using the HIP method, including Y in the analysis has a positive effect on high temperature resistance. can be given.
合金の個々の成分は、すべて重量％で表すものとする。All individual components of the alloy are expressed in percent by weight.
補正書の翻訳文提出書（特許法第１８４条の８）平成 ５ 年 ６ 月 １８日 １Submission of translation of written amendment (Article 184-8 of the Patent Law) June 18, 1993 1
Claims (12)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK110/91 | 1991-01-23 | ||
| DK011091A DK166219C (en) | 1991-01-23 | 1991-01-23 | VALVE WITH HAIR PILOT |
| PCT/DK1992/000021 WO1992013179A1 (en) | 1991-01-23 | 1992-01-22 | Valve with hard-facing |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06504830A true JPH06504830A (en) | 1994-06-02 |
Family
ID=8089853
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4503928A Pending JPH06504830A (en) | 1991-01-23 | 1992-01-22 | hardened valve |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0568598B1 (en) |
| JP (1) | JPH06504830A (en) |
| KR (1) | KR100251396B1 (en) |
| DE (1) | DE69202969T2 (en) |
| DK (1) | DK166219C (en) |
| NO (1) | NO179922C (en) |
| WO (1) | WO1992013179A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014068662A1 (en) * | 2012-10-30 | 2014-05-08 | 日鍛バルブ株式会社 | Engine valve |
| CN103882265A (en) * | 2014-02-26 | 2014-06-25 | 蚌埠市英路光电有限公司 | Nickel-base high-temperature alloy material for exhaust valves and preparation method thereof |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DK172987B1 (en) * | 1994-12-13 | 1999-11-01 | Man B & W Diesel As | Cylinder element, nickel-based alloy and application of the alloy |
| CN1080769C (en) * | 1994-12-13 | 2002-03-13 | 曼B与W狄赛尔公司 | A cylinder member and nickel-based facing |
| DE19508069C1 (en) * | 1995-02-27 | 1996-05-23 | Nu Tech Gmbh | Outlet valve for diesel IC engines |
| DK173348B1 (en) | 1996-06-07 | 2000-08-07 | Man B & W Diesel As | Exhaust valve for an internal combustion engine |
| US20130025561A1 (en) * | 2011-07-28 | 2013-01-31 | Dieter Gabriel | Bowl rim and root protection for aluminum pistons |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US727740A (en) * | 1902-09-15 | 1903-05-12 | Oliver C Bowman | Apparatus for feeding baling-presses. |
| DE970509C (en) * | 1942-05-12 | 1958-09-25 | Boehler & Co Ag Geb | Valve cone |
| FR1592212A (en) * | 1967-11-10 | 1970-05-11 | ||
| FR2341039A1 (en) * | 1976-02-11 | 1977-09-09 | Dervaux Ets | MANUFACTURING PROCESS OF MECHANICAL PARTS SUCH AS VALVES FOR THERMAL ENGINES |
| AU547863B2 (en) * | 1981-09-02 | 1985-11-07 | Exxon Research And Engineering Company | Heat resistant, alumina forming (ni+cr) based oxidation and carburisation resistant alloy |
| CH657380A5 (en) * | 1981-09-04 | 1986-08-29 | Mitsubishi Metal Corp | AT INCREASED TEMPERATURES, HEAT-RESISTANT, WEAR-RESISTANT AND TOE ALLOY ON NICKEL BASE. |
| JPS599146A (en) * | 1982-07-06 | 1984-01-18 | Mitsubishi Metal Corp | Ni alloy for valve and valve seat of engine |
| CH674019A5 (en) * | 1988-01-18 | 1990-04-30 | Asea Brown Boveri |
-
1991
- 1991-01-23 DK DK011091A patent/DK166219C/en not_active IP Right Cessation
-
1992
- 1992-01-22 JP JP4503928A patent/JPH06504830A/en active Pending
- 1992-01-22 DE DE69202969T patent/DE69202969T2/en not_active Expired - Fee Related
- 1992-01-22 WO PCT/DK1992/000021 patent/WO1992013179A1/en active IP Right Grant
- 1992-01-22 EP EP92904041A patent/EP0568598B1/en not_active Expired - Lifetime
- 1992-01-22 KR KR1019930702179A patent/KR100251396B1/en not_active IP Right Cessation
-
1993
- 1993-07-22 NO NO932645A patent/NO179922C/en unknown
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014068662A1 (en) * | 2012-10-30 | 2014-05-08 | 日鍛バルブ株式会社 | Engine valve |
| JP5763847B2 (en) * | 2012-10-30 | 2015-08-12 | 日鍛バルブ株式会社 | Engine valve |
| CN104919150A (en) * | 2012-10-30 | 2015-09-16 | 日锻汽门株式会社 | Engine valve |
| CN103882265A (en) * | 2014-02-26 | 2014-06-25 | 蚌埠市英路光电有限公司 | Nickel-base high-temperature alloy material for exhaust valves and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| NO932645D0 (en) | 1993-07-22 |
| WO1992013179A1 (en) | 1992-08-06 |
| DK166219C (en) | 1993-08-16 |
| DK166219B (en) | 1993-03-22 |
| KR100251396B1 (en) | 2000-04-15 |
| DE69202969T2 (en) | 1995-11-30 |
| NO179922C (en) | 1997-01-08 |
| KR930703526A (en) | 1993-11-30 |
| DK11091A (en) | 1992-07-24 |
| NO932645L (en) | 1993-07-22 |
| EP0568598A1 (en) | 1993-11-10 |
| NO179922B (en) | 1996-09-30 |
| DK11091D0 (en) | 1991-01-23 |
| DE69202969D1 (en) | 1995-07-20 |
| EP0568598B1 (en) | 1995-06-14 |
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