JPS589830B2 - Sintered alloy for corrosion-resistant sliding parts - Google Patents

Description

【発明の詳細な説明】 本発明は粉末冶金法による高温での耐摩摺動特性に優れ
た摺動部材に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sliding member manufactured by powder metallurgy and having excellent abrasion resistance and sliding properties at high temperatures.

近年、工業の著しい発展と共に、宇宙機器、原子力産業
等を中心に効率の向上と、高速化から潤滑要素は高温化
の傾向にあり、高温軸受など高温摺動性に優れた材料の
要求が高まっている。In recent years, with the remarkable development of industry, the lubrication elements tend to be hotter due to improvements in efficiency and higher speeds, especially in space equipment, nuclear power industries, etc., and the demand for materials with excellent high-temperature sliding properties, such as high-temperature bearings, has increased. ing.

現在高温軸受などの高温摺動材料として、一般に使われ
ているのは、工具鋼、高融点金属、超合金、サーメット
、セラミック及び黒鉛などであるが、工具鋼、高融点金
属、超合金、サーメットらは耐熱性、耐摩性に優れてい
るが、加工性が著しく悪く、材料的にも高級である為、
価格的に高く又セラミックは、価格的には比較的安価で
あるが、衝撃に弱い欠点があり黒鉛の場合強度的な問題
と、５００゜Ｃ以上の酸化性雰囲気中での耐摩性が劣化
するという問題を有している。Currently, tools commonly used as high-temperature sliding materials such as high-temperature bearings include tool steel, high-melting point metals, superalloys, cermets, ceramics, and graphite. Although they have excellent heat resistance and abrasion resistance, they have extremely poor workability and are made of high-grade materials.
Although ceramic is relatively inexpensive, it has the disadvantage of being weak against impact, and graphite has strength problems and deteriorates wear resistance in an oxidizing atmosphere at temperatures above 500°C. There is a problem.

本発明はこれらの欠点を改善し、耐熱性、耐酸化性、耐
摩性、強度特性に優れ、しかも価格的には比較的安価な
高温耐食性摺動部材用焼結合金を提供せんとするもので
ある。The present invention aims to improve these drawbacks and provide a high-temperature corrosion-resistant sintered alloy for sliding members that has excellent heat resistance, oxidation resistance, abrasion resistance, and strength characteristics, and is relatively inexpensive. be.

かかる材料は例えば以下の様な方法で製造される。Such materials are manufactured, for example, by the following method.

（以下の％は何れも重量％を現わす。）５〜１１％のＮ
ｉ粉末と４〜９％のＣｒ粉末（又はＣｒとしてのＦｅ−
Ｃｒ粉末）と、３〜８％のＣｏ粉末、Ｍｏ及びＦｅ−Ｍ
ｏ粉末をＭｏとして５〜２０及びＰｂ，Ｓｂ，Ｂｉ，Ｓ
ｎ，Ａｇの低融点金属のうち少なくとも一つを合計で１
〜１５％、残り鉄粉とを混合して１００％とし、まず冷
間で８０〜９０％の密度にプレン成形し、１２００’Ｃ
以上の還元性の雰囲気（Ｈ２又は真空）で約１時間焼結
する。(All percentages below indicate weight percentages.) 5-11% N
i powder and 4-9% Cr powder (or Fe- as Cr)
Cr powder), 3-8% Co powder, Mo and Fe-M
5 to 20 with o powder as Mo and Pb, Sb, Bi, S
At least one of the low melting point metals n, Ag in total 1
~15%, mixed with the remaining iron powder to make 100%, first cold-formed to a density of 80-90%, and then heated at 1200'C.
Sintering is performed in the above reducing atmosphere (H2 or vacuum) for about 1 hour.

得られた焼結体は密度８０〜８５％のものであるが、こ
の状態では金属マトリックスは溶体化軟化の状態にあり
、硬さはｍＨｖ ３ ０ ０以下で切削加工も含めて加
工は極めて容易である。The obtained sintered body has a density of 80 to 85%, but in this state, the metal matrix is in a state of solution softening, and the hardness is less than mHv 300, making it extremely easy to process, including cutting. It is.

この状態では硬さが低い為、耐摩性は十分と言えないが
、この後５００〜６５０°Ｃで１時間程度の時効処理を
施こすことにより、マトリックスはビツカース硬さで５
００〜６００まで硬化し、耐摩性が向上する。In this state, the hardness is low, so the wear resistance cannot be said to be sufficient, but by aging at 500 to 650°C for about 1 hour, the matrix has a Vickers hardness of 5.
It hardens from 00 to 600, improving wear resistance.

なお、粉末配合の際、ＭＯないしはＣｒは、硬い鉄化合
物の形で配合し焼結で硬質の分散相として残す方法をと
れば更に耐摩性は改善される。In addition, when blending the powder, MO or Cr may be blended in the form of a hard iron compound and left as a hard dispersed phase by sintering to further improve the wear resistance.

構成成分中、Ｎｉは耐食、耐熱性の改善の役目をするも
のであるが５％以下では効果が小さく、１１％以上とな
ると耐食性は増すが、オーステナイトが安定し、析出硬
化性が低下するので５〜１１％とした。Among the constituent components, Ni plays a role in improving corrosion resistance and heat resistance, but if it is less than 5%, the effect is small, and if it is more than 11%, corrosion resistance increases, but austenite becomes stable and precipitation hardenability decreases. It was set at 5 to 11%.

Ｃｒも耐食性、耐熱性、耐酸化性を向上させる元素であ
り、４％以下では効果が小さく、９％以上となると焼結
での溶体化軟化の状態が得られにくくなり加工が困難と
なるので４〜９％とする。Cr is also an element that improves corrosion resistance, heat resistance, and oxidation resistance, and if it is less than 4%, the effect is small, and if it is more than 9%, it becomes difficult to obtain a state of solution softening during sintering, making processing difficult. 4 to 9%.

Ｃｏはマトリックスの耐熱性の改善とマトリツクスから
のＦｅＭｏ２の析出を促進する効果があり、３％以下で
は効果が小さく、逆に８％以上となっても効果は変らず
価格を考慮して３〜８％とする。Co has the effect of improving the heat resistance of the matrix and promoting the precipitation of FeMo2 from the matrix. If it is less than 3%, the effect is small, and even if it is more than 8%, the effect remains unchanged. It shall be 8%.

Ｍｏも耐熱性と耐酸化性の改善に寄与し、時効処理によ
りマトリックスからＦｅ２Ｍｏの形で析出し硬化の主役
をなすものであるが５％以下では硬化が不十分である。Mo also contributes to the improvement of heat resistance and oxidation resistance, and is precipitated from the matrix in the form of Fe2Mo by aging treatment and plays a major role in hardening, but if it is less than 5%, hardening is insufficient.

Ｍｏの一部を硬質のＦｅ−Ｍｏ化合物で残す場合もある
が、この場合に於ても最低５％のＭｏのマトリツクス中
への固溶が必要である。In some cases, a portion of Mo may be left as a hard Fe-Mo compound, but even in this case, it is necessary to dissolve at least 5% Mo in the matrix.

しかしながら２０％以上のＭｏ量となっても、硬化量は
変らず、材質的な脆さのみ増加するので５〜２０％とし
ｔモＰｂ，Ｓｂ，Ｓｎ，Ｂｔ，Ａｇらの低融点金属は上
記の金属マトリツクス中に１〜１５％含有分布するもの
で高温雰囲気ないしは摺動中の温度上昇により溶融状態
となって空孔を介して摺動面に浸出し、潤滑の役割を演
ずる。However, even if the amount of Mo exceeds 20%, the amount of hardening will not change and only the brittleness of the material will increase. It is present in a metal matrix of 1 to 15%, and becomes molten in a high-temperature atmosphere or due to a temperature rise during sliding, and leaches into the sliding surface through pores, playing the role of lubrication.

含有量が１％以下ではこの潤滑機能が不十分であり、又
１５％以上となっても全体の強度を低下させる結果とな
るので１〜１５％とした。If the content is less than 1%, this lubricating function will be insufficient, and if the content is more than 15%, the overall strength will be reduced, so it is set at 1 to 15%.

以上に述べた様に本発明材の特徴は時効硬化性を有する
、耐食、耐摩性の金属マトリックスと高温で溶融状態と
なって優れた潤滑性を発揮する低融点金属成分より成り
、これにより潤滑油による潤滑が期待出来ない高温酸化
性雰囲気でも優れた耐摩摺動特性を発揮するものである
。As mentioned above, the characteristics of the material of the present invention are that it consists of a metal matrix that is age hardenable, corrosion resistant, and wear resistant, and a low melting point metal component that becomes molten at high temperatures and exhibits excellent lubricity. It exhibits excellent wear and sliding properties even in high-temperature oxidizing atmospheres where oil lubrication cannot be expected.

以下実施例にて更に詳細に述べる。This will be described in more detail in Examples below.

実施例 −３２５メッシュのカーボニルニッケル粉、Ｆｅ−Ｃｒ
粉末、金属コバルト粉末、及びＦｅ−Ｍｏ粉末と−２５
０メッシュのＰｂ，Ｓｂ，Ｓｎ，Ｂｉ，Ａｇを下記組成
に配合し、混合後８５％の密度に成形し、その後１２６
０℃で１時間焼結した。Example-325 mesh carbonyl nickel powder, Fe-Cr
powder, metallic cobalt powder, and Fe-Mo powder and -25
0 mesh Pb, Sb, Sn, Bi, and Ag were blended into the following composition, and after mixing, molded to a density of 85%, and then 126
Sintering was performed at 0°C for 1 hour.

得られた焼結材に対し、３５０゜Ｃでの摩耗試験を実施
した。The obtained sintered material was subjected to an abrasion test at 350°C.

（下記の組成中の数字は％を示す） Ａ Ｆｅ− ８Ｎｉ−６Ｃｒ−７Ｃｏ− ８Ｍｏ− ５
ＰｂＢ Ｆｅ− ８Ｎｉ−６Ｃｒ−７Ｃｏ− ８Ｍｏ−
５Ｐｂ−３ＳｂＣ Ｆｅ− ８Ｎｉ−６Ｃｒ−７Ｃｏ
− ８Ｍｏ− ５Ｐｂ−３ＳｎＤ Ｆｅ− ８Ｎｉ−６
Ｃｒ−７Ｃｏ− ８Ｍｏ− ５Ｐｂ−ＩＡｇＥ Ｆｅ−
１０Ｎｉ−９Ｃｒ−３Ｃｏ−１０Ｍｏ− ５Ｐｂ−３Ｂ
ｉＦ Ｆｅ− ５Ｎｉ−９Ｃｒ−８Ｃｏ−１０Ｍｏ−１
０ＰｂＧ Ｆｅ− ８Ｎｉ−３Ｃｒ−７Ｃｏ− ８Ｍｏ
−１０ＰｂＨ Ｆｅ− ８Ｎｉ−６Ｃｒ−７Ｃｏ−１５
Ｍｏ− ５Ｐｂ−３Ｓｎ− ２Ｂｉ ２ 高温摩耗試験 （テスト条件） （１）温度３５０゜Ｃ（気中） （２）接触圧力 ２ｋｇ／ｃｍ２ （３）摩擦速度 １．５ｍ／ｓｅｃ （４）摩擦距離 ３００ｍ （５）相手材 ＳＵＨ３Ｂ（硬さＨＲＣ４０）（比較
材） ２１−４Ｎ鋼 硬さＨＲＣ４０ ステライトＮｏ．６ 硬さＨＲＣ４８ 以上の実施例にて判る様に本発明材は３０００Ｇ以上の
温度雰囲気でステライト鋼に匹適する耐摩性を有し、高
温、酸化性雰囲気で使用される様な摺動部材、例えば高
温軸受、種々シール材として最適である。(Numbers in the composition below indicate %) A Fe- 8Ni-6Cr-7Co- 8Mo- 5
PbB Fe- 8Ni-6Cr-7Co- 8Mo-
5Pb-3SbC Fe- 8Ni-6Cr-7Co
- 8Mo- 5Pb-3SnD Fe- 8Ni-6
Cr-7Co- 8Mo- 5Pb-IAgE Fe-
10Ni-9Cr-3Co-10Mo-5Pb-3B
iF Fe-5Ni-9Cr-8Co-10Mo-1
0PbG Fe- 8Ni-3Cr-7Co- 8Mo
-10PbH Fe- 8Ni-6Cr-7Co-15
Mo- 5Pb-3Sn- 2Bi 2 High temperature wear test (test conditions) (1) Temperature 350°C (in air) (2) Contact pressure 2kg/cm2 (3) Friction speed 1.5m/sec (4) Friction distance 300m (5) Compatible material SUH3B (hardness HRC40) (comparison material) 21-4N steel Hardness HRC40 Stellite No. 6 Hardness HRC48 As can be seen from the above examples, the material of the present invention has wear resistance comparable to Stellite steel in a temperature atmosphere of 3000 G or more, and is suitable for sliding members used in high temperature and oxidizing atmospheres, such as Ideal for high temperature bearings and various sealing materials.

なおこの材料の製造に於て、実施例で述べた様な製造法
以外に、あらかじめマトリックス組成の粉末をアトマイ
ズ法により調製しておけば、７１〜リツクスの組織が均
質化され、時効硬化性、耐熱、耐酸化性が改善される。In the production of this material, in addition to the production method described in the examples, if a powder with a matrix composition is prepared in advance by the atomization method, the structure of 71 to 1000x will be homogenized, and the age hardenability and Heat resistance and oxidation resistance are improved.

又潤滑成分を含有させる方法は焼結前に粉末で混合する
方法以外に焼結、熱処理後含浸させても全く同じ効果が
得られる。In addition to the method of incorporating a lubricating component in the form of powder before sintering, the same effect can be obtained by impregnating it after sintering and heat treatment.

Claims (1)

【特許請求の範囲】[Claims] １ 重量％でＮｉ５〜１１％、Ｃｒ４〜９％、Ｃｏ３〜
８％、ＭＯ５〜２０％、残り鉄の組成よりなる析出硬化
性を有する金属マトリックス中に、Ｐｂ、Ｓｂ，Ｂｉ，
Ｓｎ，Ａｇの低融点金属のうち少なくとも一つを合計重
量％で１〜１５％含有する高温での摺動特性に優れた耐
食性摺動部材用焼結合金。1% by weight: Ni5-11%, Cr4-9%, Co3-
Pb, Sb, Bi,
A sintered alloy for a sliding member having excellent corrosion resistance and excellent sliding properties at high temperatures, containing at least one of low melting point metals such as Sn and Ag in a total weight percent of 1 to 15%.