JP5744678B2 - Precipitation hardening type metastable austenitic stainless steel wire excellent in fatigue resistance and method for producing the same - Google Patents
Precipitation hardening type metastable austenitic stainless steel wire excellent in fatigue resistance and method for producing the same Download PDFInfo
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- 229910000963 austenitic stainless steel Inorganic materials 0.000 title claims description 28
- 238000004881 precipitation hardening Methods 0.000 title claims description 28
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 230000032683 aging Effects 0.000 claims description 22
- 229910001220 stainless steel Inorganic materials 0.000 claims description 15
- 229910000734 martensite Inorganic materials 0.000 claims description 12
- 239000012299 nitrogen atmosphere Substances 0.000 claims description 8
- 229910001566 austenite Inorganic materials 0.000 claims description 5
- 229910052802 copper Inorganic materials 0.000 claims description 4
- 238000005482 strain hardening Methods 0.000 claims description 3
- 239000012535 impurity Substances 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 description 35
- 239000010959 steel Substances 0.000 description 35
- 239000000047 product Substances 0.000 description 17
- 229910052750 molybdenum Inorganic materials 0.000 description 12
- 229910052757 nitrogen Inorganic materials 0.000 description 11
- 229910052782 aluminium Inorganic materials 0.000 description 10
- 238000005452 bending Methods 0.000 description 9
- 230000035882 stress Effects 0.000 description 9
- 150000004767 nitrides Chemical class 0.000 description 8
- 230000007423 decrease Effects 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 239000002244 precipitate Substances 0.000 description 7
- 229910052719 titanium Inorganic materials 0.000 description 7
- 238000005491 wire drawing Methods 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 6
- 239000010935 stainless steel Substances 0.000 description 6
- 238000010622 cold drawing Methods 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 5
- 238000011156 evaluation Methods 0.000 description 5
- 238000001556 precipitation Methods 0.000 description 5
- 239000012298 atmosphere Substances 0.000 description 4
- 229910052758 niobium Inorganic materials 0.000 description 4
- 239000002344 surface layer Substances 0.000 description 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 3
- 230000005415 magnetization Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 229920006395 saturated elastomer Polymers 0.000 description 3
- 238000005728 strengthening Methods 0.000 description 3
- 229910052715 tantalum Inorganic materials 0.000 description 3
- 229910052721 tungsten Inorganic materials 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000005098 hot rolling Methods 0.000 description 2
- 229910000765 intermetallic Inorganic materials 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910052720 vanadium Inorganic materials 0.000 description 2
- -1 AlN and TiN Chemical class 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 206010070834 Sensitisation Diseases 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000009661 fatigue test Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000010309 melting process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 230000008313 sensitization Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 238000009864 tensile test Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
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Description
本発明は、ばね等の耐疲労性に優れた２０００Ｎ／ｍｍ2以上の引張強さを有する高強度且つ耐疲労性に優れる製品に係わり、Ａｌ，Ｍｏ，Ｔｉ，Ｏ，Ｎ等を制御して粗大介在物を抑制し、微細析出物を制御して表層圧縮残留応力を付与した析出硬化型準安定オーステナイト系ステンレス鋼線およびその製造方法に関するものである。 The present invention relates to a high strength and excellent fatigue resistance product having a tensile strength of 2000 N / mm 2 or more excellent in fatigue resistance such as a spring, and controlling Al, Mo, Ti, O, N, etc. The present invention relates to a precipitation hardening type metastable austenitic stainless steel wire which suppresses coarse inclusions, controls fine precipitates and imparts a compressive residual stress on the surface layer, and a method for producing the same.
従来、高強度ステンレス鋼線から成型されたばね疲労性に優れた高強度ステンレス製品はＳＵＳ３０４，ＳＵＳ３１６のステンレス鋼線材を素材として加工・成型されてきた。これら製品の疲労は鋼線の繰り返し曲げ方向、または、ねじり変形方向の疲労特性が求められる。しかしながら、これらの鋼線材から加工された製品は疲労強度が普通鋼線に比べ劣るという欠点があった。そのため、水素，結晶粒径を規定した２０００Ｎ／ｍｍ2以上の引張強さを有する高強度ばね用の準安定オーステナイト系ステンレス鋼線が提案されている（下記特許文献１）。しかしながら、本発明者らの検討によれば、疲労特性の向上は見られるものの目標の疲労強度（例えば回転曲げ応力≧５００Ｎ／ｍｍ2）を満足していない。
Conventionally, high-strength stainless steel products excellent in spring fatigue formed from high-strength stainless steel wires have been processed and molded from stainless steel wires of SUS304 and SUS316. The fatigue of these products requires fatigue characteristics in the direction of repeated bending or torsional deformation of steel wires. However, the products processed from these steel wires have the disadvantage that their fatigue strength is inferior to that of ordinary steel wires. Therefore, a metastable austenitic stainless steel wire for a high-strength spring having a tensile strength of 2000 N / mm 2 or more in which hydrogen and crystal grain size are defined has been proposed (
一方、疲労強度の向上には、時効処理，析出硬化処理が有効であり、ＳＵＳ３０４系にＭｏ，Ｃｏ，Ｎを添加した高強度ばねを５００〜５５０℃で低温焼鈍すること（下記特許文献２）、また、Ａｌ，Ｃｕ，Ｍｏ等を添加したオーステナイト系の析出硬化型ステンレス鋼が提案されている（下記特許文献３）。
On the other hand, aging treatment and precipitation hardening treatment are effective for improving fatigue strength. A high-strength spring in which Mo, Co, and N are added to SUS304 is annealed at a low temperature of 500 to 550 ° C. (
また、酸素を抑制してＮ，Ｍｏ，Ｔｉ，Ｎｂ等を添加し、加工誘起マルテンサイト量を制御した耐疲労性に優れた準安定オーステナイト系ステンレス鋼が提案されている（下記特許文献４）。また、準安定オーステナイト系ステンレス鋼にＭｏ，Ｔｉを添加した高強度鋼板が提案されている（下記特許文献５）。更に、準安定オーステナイト系ステンレス鋼にＭｏ，Ａｌを添加した高強度の耐熱鋼板が提案されている（特許文献６）。しかしながら、いずれも要求される強度・耐疲労特性（鋼線の曲げ、または、ねじり方向の疲労特性）を兼ね備えていない。
Further, a metastable austenitic stainless steel excellent in fatigue resistance in which oxygen is suppressed and N, Mo, Ti, Nb or the like is added to control the amount of work-induced martensite has been proposed (
そのため、従来の高強度ステンレス鋼では、十分な強度と疲労特性（鋼線の曲げ、または、ねじり方向の疲労特性）を兼ね備えることができなかった。 Therefore, conventional high-strength stainless steels could not have sufficient strength and fatigue characteristics (bending of steel wire or fatigue characteristics in the torsional direction).
本発明の目的は、高強度・高耐疲労製品用の素材である析出硬化型の準安定オーステナイト系ステンレス鋼線を提供し、従来の高強度・高耐疲労製品の強度と耐疲労性の両特性を大幅に改善することにある。 An object of the present invention is to provide a precipitation hardening type metastable austenitic stainless steel wire that is a material for high strength and high fatigue resistance products, and to provide both strength and fatigue resistance of conventional high strength and high fatigue resistance products. It is to greatly improve the characteristics.
本発明者らは、上記課題を解決するために種々検討した結果、析出硬化型の準安定オーステナイト系ステンレス鋼において、1)Ａｌ，Ｍｏを複合添加し、加工誘起マルテンサイト量を制御して析出硬化にて強度を飛躍的に高め、且つ、2)Ａｌ，Ｔｉ，Ｎ量の関係を制御して粗大窒化物を抑制し、また、3)製品を窒素雰囲気中で時効して表層圧縮残留応力を付与することで、複合の相乗効果により強度特性を維持しつつ耐疲労特性を飛躍的に高めることを見出した。本発明は、上記知見に基づいてなされたものであり、その要旨とするところは以下の通りである。 As a result of various studies to solve the above-mentioned problems, the present inventors, as a result of precipitation hardening type metastable austenitic stainless steel, 1) Al and Mo are added in combination, and the amount of work-induced martensite is controlled to precipitate. The strength is dramatically increased by hardening, and 2) the relationship between the amount of Al, Ti, and N is controlled to suppress coarse nitrides, and 3) the product is aged in a nitrogen atmosphere to compress the surface compressive residual stress. It has been found that the fatigue resistance can be drastically improved while maintaining the strength by the combined synergistic effect. This invention is made | formed based on the said knowledge, The place made into the summary is as follows.
（１）質量％で、Ｃ：０．０２〜０．１５％、Ｓｉ：０．１〜４．０％、Ｍｎ：０．１〜１０．０％、Ｎｉ：３．０〜９．０％、Ｃｒ：１３．０〜１９．０％、Ｍｏ：０．８超〜4．０％、Ａｌ：０．３５〜３．０％、Ｔｉ：０．０１〜０．２０％、Ｎ：０．０５％以下、Ｏ：０．００４％以下を含有し、残部Ｆｅおよび不可避的不純物からなり、
下記（a）式で表されるＭｄ30値が−１０〜７０であり、下記(b)式で規定されるＮg値がＮ含有量以上０．１０以下であり、引張強さが２０００Ｎ／ｍｍ２以上であることを特徴とする耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。
Ｍｄ30＝５５１−４６２（Ｃ＋Ｎ）−９．２Ｓｉ―８．１Ｍｎ
―２９（Ｎｉ＋Ｃｕ）−１３．７Ｃｒ―１８．５Ｍｏ・・・・・（a）
Ｎg＝0.002／（Ａｌ×Ｔｉ） ・・・・・（b）
（２）マルテンサイト量が２５体積％以上、８５体積％未満であることを特徴とする（１）に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。
(1) By mass%, C: 0.02 to 0.15%, Si: 0.1 to 4.0%, Mn: 0.1 to 10.0%, Ni: 3.0 to 9.0% Cr: 13.0 to 19.0%, Mo: more than 0.8 to 4.0%, Al: 0.35 to 3.0%, Ti: 0.01 to 0.20%, N: 0.0. 05% or less, O: 0.004% or less, balance Fe and unavoidable impurities,
The Md30 value represented by the following formula (a) is -10 to 70, the Ng value defined by the following formula (b) is N content or more and 0.10 or less, and the tensile strength is 2000 N / mm 2. A precipitation hardening type metastable austenitic stainless steel wire with excellent fatigue resistance, characterized by the above.
Md30 = 551-462 (C + N) -9.2Si-8.1Mn
-29 (Ni + Cu) -13.7Cr-18.5Mo (a)
Ng = 0.002 / (Al × Ti) (b)
(2) The precipitation hardening type metastable austenitic stainless steel wire having excellent fatigue resistance according to (1), wherein the martensite content is 25% by volume or more and less than 85% by volume.
（３）更に質量％で、Ｖ：０．０５〜２．０％、Ｎｂ：０．０５〜２．０％、Ｗ：０．０５〜２．０％、Ｔａ：０．０５〜２．０％の内、１種類以上を含有することを特徴とする（１）または（２）に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。
（４）更に質量％で、Ｃｏ：０．１〜４．０％を含有することを特徴とする（１）〜（３）のいずれか一項に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。
（５）更に質量％で、Ｃｕ：０．１以上、２．０％未満を含有することを特徴とする（１）〜（４）のいずれか一項に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。
(3) Further, by mass%, V: 0.05 to 2.0%, Nb: 0.05 to 2.0%, W: 0.05 to 2.0%, Ta: 0.05 to 2.0 The precipitation hardening type metastable austenitic stainless steel wire excellent in fatigue resistance as described in (1) or (2), wherein the wire contains one or more of%.
(4) Precipitation hardening type excellent in fatigue resistance according to any one of (1) to (3), further comprising, by mass%, Co: 0.1 to 4.0% Metastable austenitic stainless steel wire.
(5) Precipitation excellent in fatigue resistance according to any one of (1) to (4), further comprising Cu: 0.1 or more and less than 2.0% by mass% Hardening type metastable austenitic stainless steel wire.
（６）更に質量％で、Ｂ：０．０００５〜０．０１５％を含有することを特徴とする（１）〜（５）のいずれか一項に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。
（７）更に質量％で、Ｃａ：０．０００５〜０．０１％、Ｍｇ：０．０００５〜０．０１％、ＲＥＭ：０．０００５〜０．０５％の内、１種類以上を含有することを特徴とする（１）〜（６）のいずれか一項に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。
（８）（１）〜（７）のいずれか一項に記載のステンレス鋼線の製造方法であって、冷間加工後に３００〜６００℃で時効処理を施すことを特徴とする耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線の製造方法。
（９）前記時効処理が窒素雰囲気で施されることを特徴とする（８）に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線の製造方法。
（１０）（１）〜（７）のいずれか一項に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線からなることを特徴とする、ばね。
(6) Precipitation hardening type excellent in fatigue resistance according to any one of (1) to (5), further comprising, by mass%, B: 0.0005 to 0.015% Metastable austenitic stainless steel wire.
(7) Further, by mass%, it contains at least one of Ca: 0.0005 to 0.01%, Mg: 0.0005 to 0.01%, REM: 0.0005 to 0.05%. The precipitation hardening type metastable austenitic stainless steel wire excellent in fatigue resistance according to any one of (1) to (6).
(8) A method for producing a stainless steel wire according to any one of (1) to (7), wherein the steel wire is subjected to aging treatment at 300 to 600 ° C after cold working. A method for producing an excellent precipitation hardening type metastable austenitic stainless steel wire.
(9) The method for producing a precipitation hardening type metastable austenitic stainless steel wire excellent in fatigue resistance according to (8), wherein the aging treatment is performed in a nitrogen atmosphere.
(10) A spring comprising a precipitation hardening type metastable austenitic stainless steel wire excellent in fatigue resistance according to any one of (1) to (7).
本発明による耐疲労性に優れた準安定オーステナイト系ステンレス鋼線は、２０００Ｎ／ｍｍ2以上の強度に加え、優れた耐疲労特性を合わせ持つため、飛躍的に強度と耐疲労特性の両特性に優れたばね等の部品を安価に提供する効果を発揮する。 The metastable austenitic stainless steel wire with excellent fatigue resistance according to the present invention has excellent fatigue resistance characteristics in addition to the strength of 2000 N / mm 2 or more, so both the strength and fatigue resistance characteristics are dramatically improved. Demonstrates the effect of providing excellent springs and other parts at low cost.
以下に、先ず、本発明の（１）、（２）に記載の限定理由について説明する。 Below, the reason for limitation described in (1) and (2) of the present invention will be described first.
Ｃは、伸線加工後に高強度を得るために、０．０２％以上（以下は全て質量％）添加する。しかしながら、０．１５％を超えて添加すると、粒界に粗大Ｃｒ炭化物が析出し、延靱性が低下して耐疲労特性が劣化することから、上限を０．１５％とする。好ましい範囲は、０．０４〜０．１２％である。 C is added in an amount of 0.02% or more (the following is all by mass%) in order to obtain high strength after wire drawing. However, if added over 0.15%, coarse Cr carbide precipitates at the grain boundaries, the toughness decreases and the fatigue resistance deteriorates, so the upper limit is made 0.15%. A preferable range is 0.04 to 0.12%.
Ｓｉは、脱酸のために０．１％以上添加する。しかしながら、４．０％を超えて添加するとその効果は飽和するばかりか製造性が悪くなり、また、延靱性が劣化して耐疲労特性が劣化するため、上限を４．０％にする。好ましい範囲は、０．５〜２．０％である。 Si is added in an amount of 0.1% or more for deoxidation. However, if added over 4.0%, the effect is saturated and the manufacturability is deteriorated, and the ductility is deteriorated and the fatigue resistance is deteriorated, so the upper limit is made 4.0%. A preferable range is 0.5 to 2.0%.
Ｍｎは、脱酸のために０．１％以上添加する。しかしながら、１０．０％を超えて添加すると、強度が低下して耐疲労特性が劣化するため、上限を１０．０％にする。好ましい範囲は、０．５〜５．０％である。 Mn is added in an amount of 0.1% or more for deoxidation. However, if added over 10.0%, the strength decreases and the fatigue resistance deteriorates, so the upper limit is made 10.0%. A preferable range is 0.5 to 5.0%.
Ｎｉは、延靱性を確保して耐疲労特性を向上させるため、３．０％以上添加する。しかしながら、９．０％を超えて添加すると、Ｍｄ３０値が低下して強度が低下し、耐疲労特性が劣化するため、上限を９．０％にする。好ましい範囲は、４．０〜８．０％である。 Ni is added in an amount of 3.0% or more in order to ensure ductility and improve fatigue resistance. However, if added over 9.0%, the Md30 value decreases, the strength decreases, and the fatigue resistance deteriorates, so the upper limit is made 9.0%. A preferable range is 4.0 to 8.0%.
Ｃｒは、耐食性を確保するため、１３．０％以上添加する。しかしながら、１９．０％を超えて添加すると、延靱性が劣化して疲労強度が低下するため、上限を１９．０％にする。好ましい範囲は、１４．０〜１８．０％である。 Cr is added in an amount of 13.0% or more to ensure corrosion resistance. However, if added over 19.0%, ductility deteriorates and fatigue strength decreases, so the upper limit is made 19.0%. A preferable range is 14.0 to 18.0%.
Ｍｏは、伸線後の３００〜６００℃での時効処理によりＭｏ系の微細な金属間クラスターを微細析出させて、延靱性を損なうことなく高強度化して耐疲労特性を向上させる有効な元素であり、０．８超％添加する。しかしながら、４．０％を超えて添加すると、その効果は飽和するばかりか、逆に延靱性が低下して耐疲労特性を劣化させるため、上限を４．０％にする。 Mo is an effective element that finely precipitates Mo-based intermetallic clusters by aging treatment at 300 to 600 ° C. after wire drawing, increases the strength without impairing ductility, and improves fatigue resistance. Yes, add over 0.8% . However, if adding over 4.0%, the effect is not only saturated, since the rolled toughness conversely deteriorate the fatigue resistance decreases, you limit to 4.0%.
Ａｌは、伸線後の３００〜６００℃での時効処理により微細なＡｌ系の金属間化合物を微細析出させて、延靱性を損なうことなく、高強度化して耐疲労性を向上させる有効な元素であり、０．３５％以上添加する。しかしながら、３．０％を超えて添加してもその効果は飽和するし、逆に延靱性を低下させて耐疲労特性を劣化させる。そのため、上限を３．０％とする。好ましい範囲は、０．５〜１．５％である。更に好ましい範囲は、０．７〜１．３％である。 Al is an effective element that finely precipitates a fine Al-based intermetallic compound by aging treatment at 300 to 600 ° C. after wire drawing to increase strength and improve fatigue resistance without impairing ductility. And 0.35% or more is added. However, even if added over 3.0%, the effect is saturated, and conversely, the toughness is lowered and the fatigue resistance is deteriorated. Therefore, the upper limit is made 3.0%. A preferable range is 0.5 to 1.5%. A more preferable range is 0.7 to 1.3%.
Ｔｉは、Ｎ，Ｏの抑制と共に耐疲労特性を向上させる元素であり、粗大なＡｌＮの析出を防止し、耐疲労特性を向上させるため、０．０１％以上添加する。しかしながら、０．２０％を超えて添加すると粗大なＴｉ系析出物（ＴｉＮ，Ｔｉ酸化物等）が生成し、逆に耐疲労特性が劣化するため、上限を０．２０％にする。好ましい範囲は、０．０３以上０．１０％未満である。 Ti is an element that improves fatigue resistance as well as suppressing N and O, and is added in an amount of 0.01% or more in order to prevent coarse AlN precipitation and improve fatigue resistance. However, if added over 0.20%, coarse Ti-based precipitates (TiN, Ti oxide, etc.) are generated, and the fatigue resistance is deteriorated conversely, so the upper limit is made 0.20%. A preferable range is 0.03 or more and less than 0.10%.
Ｎは、強度に寄与する元素であるが、ＡｌＮ，ＴｉＮ等の粗大窒化物を生成し、耐疲労特性を劣化させる。そのため、粗大窒化物を抑制するために０．０５％以下に限定する。好ましい範囲は、０．００５〜０．０３％である。 N is an element that contributes to strength, but generates coarse nitrides such as AlN and TiN, and degrades fatigue resistance. Therefore, in order to suppress coarse nitride, it is limited to 0.05% or less. A preferred range is 0.005 to 0.03%.
Ｏは、粗大酸化物の生成を抑制して耐疲労特性を向上させるため、Ｔｉ，Ｎ量の制御と共に、０．００４％以下に限定する。好ましい範囲は、０．０００３〜０．００３％である。 In order to suppress the formation of coarse oxides and improve fatigue resistance, O is limited to 0.004% or less along with the control of Ti and N amounts. A preferable range is 0.0003 to 0.003%.
本発明の鋼線の金属相は、オーステナイト相、後述する冷間加工で発生するマルテンサイト相からなる。このうちマルテンサイト相の割合は、鋼線および鋼帯の強度および耐疲労特性を向上させるために、２５体積％以上に限定する。しかしながら、８５体積％以上になると延靱性が劣化し、逆に耐疲労特性が劣化する。そのため、上限を８５体積％未満に限定することが好ましく、更に好ましい範囲は、３５〜６５体積％である。 The metal phase of the steel wire of the present invention is composed of an austenite phase and a martensite phase generated by cold working described later. Among these, the ratio of the martensite phase is limited to 25% by volume or more in order to improve the strength and fatigue resistance of the steel wire and steel strip. However, if it is 85 volume% or more, ductility will deteriorate and conversely fatigue resistance will deteriorate. Therefore, it is preferable to limit an upper limit to less than 85 volume%, and a more preferable range is 35-65 volume%.
Ｍｄ30値は、伸線後の加工誘起マルテンサイト量と成分の関係を調査して得られた指標であり、高強度と延性を確保するためにＭｄ30値を制御する必要がある。Ｍｄ３０値が−1０未満の場合、オーステナイト相の安定度が増し、伸線加工では高強度化しなくなるばかりか、３００〜６００℃で実施する析出強化量も低減し、耐疲労特性が劣化する。一方、Ｍｄ３０値が７０を超えると、伸線加工で過剰な加工誘起マルテンサイト相が生成し、伸線加工後の延靱性が低下し、耐疲労特性が劣化する。そのため、Ｍｄ３０値を−1０〜７０に限定する。好ましい範囲は、1０〜６０である。更に好ましい範囲は、２０〜５０である。 The Md30 value is an index obtained by investigating the relationship between the amount of work-induced martensite after drawing and the component, and it is necessary to control the Md30 value in order to ensure high strength and ductility. When the Md30 value is less than -10, the stability of the austenite phase is increased, and not only the strength is not increased by wire drawing, but also the precipitation strengthening amount carried out at 300 to 600 ° C. is reduced, and the fatigue resistance is deteriorated. On the other hand, if the Md30 value exceeds 70, an excessive work-induced martensite phase is generated by wire drawing, the ductility after wire drawing is reduced, and the fatigue resistance is deteriorated. Therefore, the Md30 value is limited to -10 to 70. A preferred range is 10-60. A more preferred range is 20-50.
Ｎg値は、本発明者らがＡｌ，ＴｉおよびＮ量と粗大窒化物の生成による耐疲労特性の劣化の関係を調査した結果得られた指標である。後述する実施例で示すように、Ｎｇ値がＮ量より小さくなると粗大窒化物（ＡｌＮ，ＴｉＮ等）が生成し、耐疲労特性が劣化する。そのため、Ｎｇ値がＮ量以上になるよう制御する。一方、Ｎｇ値が０．１０より大きくなると析出硬化代が小さく強度に劣るため上限値を０．１０とし、好ましくは、０．０８以下である。鋼線の引張強さは、耐疲労特性に大きく影響を及ぼし、介在物等を制御していれば、鋼線の引張強さが２０００Ｎ／ｍｍ2以上であれば良好な耐疲労特性が得られる。そのため、鋼線の引張強さを２０００Ｎ／ｍｍ2以上に限定する。好ましい範囲は、２２００〜３５００Ｎ／ｍｍ2である。 The Ng value is an index obtained as a result of investigating the relationship between the amounts of Al, Ti and N and the deterioration of fatigue resistance due to the formation of coarse nitrides. As shown in the examples described later, when the Ng value is smaller than the N amount, coarse nitrides (AlN, TiN, etc.) are generated and the fatigue resistance is deteriorated. Therefore, control is performed so that the Ng value is equal to or greater than the N amount. On the other hand, if the Ng value is greater than 0.10, the precipitation hardening margin is small and the strength is inferior, so the upper limit value is 0.10, and preferably 0.08 or less. The tensile strength of the steel wire greatly affects the fatigue resistance. If the inclusions are controlled, good fatigue resistance can be obtained if the tensile strength of the steel wire is 2000 N / mm 2 or more. . Therefore, the tensile strength of the steel wire is limited to 2000 N / mm 2 or more. A preferred range is 2200-3500 N / mm 2 .
次に、本発明の（３）に記載の限定理由について説明する。 Next, the reason for limitation described in (3) of the present invention will be described.
Ｖ，Ｎｂ，Ｗ，Ｔａは、炭窒化物を形成して結晶粒径を微細にして耐疲労特性を改善するため、必要に応じて、Ｖ：０．０５〜２．０％、Ｎｂ：０．０５〜２．０％、Ｗ：０．０５〜２．０％、Ｔａ：０．０５〜２．０％の内、１種類以上を添加する。しかしながら、上限を超えて添加すると粗大介在物が生成し、延靱性が低下し、耐疲労特性が劣化する。好ましい各元素の範囲は、０．１〜１．０％である。 V, Nb, W, and Ta form carbonitrides to refine the crystal grain size and improve fatigue resistance. Therefore, V: 0.05 to 2.0%, Nb: 0 as necessary. One or more of 0.05 to 2.0%, W: 0.05 to 2.0%, and Ta: 0.05 to 2.0% are added. However, if added over the upper limit, coarse inclusions are generated, ductility is lowered, and fatigue resistance is deteriorated. A preferable range of each element is 0.1 to 1.0%.
次に、本発明の（４）に記載の限定理由について説明する。 Next, the reason for limitation described in (4) of the present invention will be described.
Ｃｏは、延靱性を確保して耐疲労特性を向上させるため、必要に応じて、０．１％以上添加する。しかしながら、４．０％を超えて添加すると、強度が低下して耐疲労特性が劣化するため、上限を４．０％にする。好ましい範囲は、０．５〜３．０％である。 Co is added in an amount of 0.1% or more as necessary to ensure ductility and improve fatigue resistance. However, if added over 4.0%, the strength decreases and the fatigue resistance deteriorates, so the upper limit is made 4.0%. A preferable range is 0.5 to 3.0%.
次に、本発明の（５）に記載の限定理由について説明する。 Next, the reason for limitation described in (5) of the present invention will be described.
Ｃｕは、伸線後の３００〜６００℃での時効処理により微細なＣｕ系の金属間化合物を微細析出させて、延靱性を損なうことなく、高強度化して耐疲労性を向上させる有効な元素であり、必要に応じて、０．１％以上添加する。しかしながら、２．０％以上添加すると、逆に軟質化して耐疲労特性を低下させる。そのため、上限を２．０％未満とする。好ましい範囲は、０．５〜１．５％である。 Cu is an effective element that precipitates a fine Cu-based intermetallic compound by aging treatment at 300 to 600 ° C. after wire drawing to increase the strength and improve the fatigue resistance without impairing the ductility. If necessary, 0.1% or more is added. However, addition of 2.0% or more conversely softens and deteriorates fatigue resistance. Therefore, the upper limit is made less than 2.0%. A preferable range is 0.5 to 1.5%.
次に、本発明の（６）に記載の限定理由について説明する。 Next, the reason for limitation described in (6) of the present invention will be described.
Ｂは、熱間製造性および靱性を向上させるため、必要に応じて、０．０００５％以上を添加する。しかしながら、０．０１５％を超えて添加するとボライドが生成するため、逆に延靱性が低下して、耐疲労特性が低下する。そのため、上限を０．０１５％にする。好ましい範囲は、０．００１〜０．０１％である。 In order to improve hot manufacturability and toughness, B is added in an amount of 0.0005% or more as necessary. However, if added over 0.015%, boride is generated, and conversely, ductility is lowered and fatigue resistance is lowered. Therefore, the upper limit is made 0.015%. A preferred range is 0.001 to 0.01%.
次に、本発明の（７）に記載の限定理由について説明する。 Next, the reason for limitation described in (7) of the present invention will be described.
Ｃａ，Ｍｇ，ＲＥＭは、脱酸のため、必要に応じて、Ｃａ：０．０００５〜０．０１％、Ｍｇ：０．０００５〜０．０１％、ＲＥＭ：０．０００５〜０．０５％の１種以上を添加する。しかしながら、各上限を超えて添加すると粗大介在物が生成して耐疲労特性が低下する。 Ca, Mg, and REM are for deoxidation, and if necessary, Ca: 0.0005 to 0.01%, Mg: 0.0005 to 0.01%, REM: 0.0005 to 0.05% Add one or more. However, if it is added in excess of each upper limit, coarse inclusions are generated and the fatigue resistance is lowered.
次に、本発明の（８）に記載の限定理由について説明する。 Next, the reason for limitation described in (8) of the present invention will be described.
本発明の耐疲労性に優れた鋼線または鋼帯の製造においては、熱間圧延で製造される線材または熱延鋼帯から通常実施される冷間伸線（加工率３０〜９０％），冷間圧延（３０〜９０％），熱処理の組み合わせで製造されることが経済的に効果的である。 In the production of a steel wire or steel strip excellent in fatigue resistance according to the present invention, cold drawing (working rate: 30 to 90%) usually performed from a wire rod or hot rolled steel strip produced by hot rolling, It is economically effective to be manufactured by a combination of cold rolling (30 to 90%) and heat treatment.
ここで、本発明で用いることが出来る線材は、上述した本発明の鋼線が有する組成、Ｍｄ３０値範囲、及びＮｇ値範囲を満たすものであれば良い。 Here, the wire that can be used in the present invention only needs to satisfy the above-described composition, Md30 value range, and Ng value range of the steel wire of the present invention.
また、前述したようにＡｌ，Ｍｏ，Ｃｕ系の微細析出物やクラスターを微細析出させて、延靱性を損なうことなく高強度化して耐疲労特性を向上させるために、前記の冷間加工後に時効処理を行う。この時、３００℃未満では析出強化が不十分であり、６００℃を超えると過時効となる。そのため、３００℃〜６００℃の温度範囲に限定する。好ましくは、４００〜５５０℃である。また、時効処理の時間は、３分未満では析出強化が不十分であり、１００時間を超えると過時効となる。そのため、時効時間は、３分〜１００時間の範囲である。 In addition, as described above, Al, Mo, Cu-based fine precipitates and clusters are finely precipitated to increase the strength without impairing the ductility and to improve the fatigue resistance. Process. At this time, precipitation strengthening is insufficient when the temperature is lower than 300 ° C, and overaging occurs when the temperature exceeds 600 ° C. Therefore, it limits to the temperature range of 300 to 600 degreeC. Preferably, it is 400-550 degreeC. Further, when the aging treatment time is less than 3 minutes, precipitation strengthening is insufficient, and when it exceeds 100 hours, overaging occurs. Therefore, the aging time is in the range of 3 minutes to 100 hours.
次に、本発明の（９）に記載の限定理由について説明する。 Next, the reason for limitation described in (9) of the present invention will be described.
耐疲労特性を向上させるには表層圧縮残留応力を付与することが有効であり、窒素雰囲気中で時効処理することで表層に窒素を固溶、または微細な窒化物を生成させることが有効である。そのため、必要に応じて、窒素雰囲気中で時効処理を実施する。好ましくは、無酸化の雰囲気にて、０．５〜１．０気圧の窒素分圧下で実施する。 In order to improve fatigue resistance, it is effective to give surface layer compressive residual stress, and it is effective to form solid nitride or fine nitride in the surface layer by aging treatment in a nitrogen atmosphere. . Therefore, an aging treatment is performed in a nitrogen atmosphere as necessary. Preferably, it is carried out in a non-oxidizing atmosphere under a nitrogen partial pressure of 0.5 to 1.0 atm.
次に、本発明の（１０）に記載の限定理由について説明する。 Next, the reason for limitation described in (10) of the present invention will be described.
本発明の耐疲労性に優れるステンレス鋼線は、特にばね製品として好適に用いることができる。これらの製品は、特に耐疲労性が求められるため、本発明の意義が大きい。ばね製品として用いる場合は、前述の鋼線材や熱延鋼帯（鋼板）を冷間伸線（加工率３０〜９０％）、冷間圧延（加工率３０〜９０％）、熱処理の組み合わせ、及びコイリング，曲成形するなどして所望の形状に冷間加工し、その後時効処理を行う。 The stainless steel wire excellent in fatigue resistance of the present invention can be suitably used particularly as a spring product. Since these products are particularly required to have fatigue resistance, the significance of the present invention is great. When used as a spring product, the above-mentioned steel wire rod or hot-rolled steel strip (steel plate) is cold-drawn (processing rate 30 to 90%), cold-rolled (processing rate 30 to 90%), a combination of heat treatment, and It is cold-worked to the desired shape by coiling, bending, etc., and then aging treatment is performed.
以下に本発明の実施例について説明する。表１−１、表１−２に実施例の鋼の化学組成を示す。 Examples of the present invention will be described below. Tables 1-1 and 1-2 show the chemical compositions of the steels of the examples.
これらの化学組成の鋼は、ステンレス鋼の安価溶製プロセスであるＡＯＤ溶製を想定し、１００ｋｇの真空溶解炉にて溶解し、φ１８０ｍｍの鋳片に鋳造し、その鋳片をφ５．５ｍｍまで熱間の線材圧延を行い、１０００℃で熱間圧延を終了した。その後、溶体化処理として１０５０℃で３０分保持した後に水冷し、酸洗を行い線材とした。その後、φ３．０ｍｍまで冷間で伸線加工を施し、１０５０℃で中間ストランド焼鈍を施し、引き続き１．５ｍｍまで冷間で伸線加工を施した。その後、大気にて45０℃で３０分の時効処理を行い、高強度ステンレス鋼線の製品とした。 Assuming AOD melting, which is a cheap melting process for stainless steel, these chemical compositions are melted in a 100 kg vacuum melting furnace, cast into a slab of φ180 mm, and the slab is reduced to φ5.5 mm Hot wire rolling was performed, and the hot rolling was terminated at 1000 ° C. Then, after hold | maintaining at 1050 degreeC as a solution treatment for 30 minutes, it cooled with water, pickled, and was set as the wire. Thereafter, cold drawing was performed to φ3.0 mm, intermediate strand annealing was performed at 1050 ° C., and then cold drawing was performed to 1.5 mm. Thereafter, an aging treatment was performed in the atmosphere at 450 ° C. for 30 minutes to obtain a high-strength stainless steel wire product.
そして、鋼線製品の機械的性質，マルテンサイト量，疲労強度を評価した。その評価結果を表２−１、表２−２に示す。 The mechanical properties, martensite content, and fatigue strength of the steel wire products were evaluated. The evaluation results are shown in Tables 2-1 and 2-2.
鋼線の機械的性質は、ＪＩＳ Ｚ ２２４１の引張試験での引張強さと破断絞りにて評価した。本発明例の鋼線の製品では、全て２０００Ｎ／ｍｍ2以上，破断絞りが３０％以上であり、強度と延性に優れていた。 The mechanical properties of the steel wire were evaluated by the tensile strength and breaking drawing in the tensile test of JIS Z2241. The steel wire products of the examples of the present invention were all 2000 N / mm 2 or more, the fracture drawing was 30% or more, and were excellent in strength and ductility.
鋼線のマルテンサイト（α’）量は、直流磁束計にて１００００ Ｏｅの磁場を付与した時の飽和磁化値を測定し、以下の(A)〜(C)式にて求めた。
α’量(vol.%)=σs／σs(bcc)×100 ----------------(Ａ)
σs；飽和磁化値（Ｔ），σs(bcc)；100%α‘変態した時の飽和磁化値（計算値）
σs(bcc)=2.14-0.030Creq -----------------(Ｂ)
Creq=Cr+1.8Si+Mo+0.5Ni+0.9Mn+3.6(C+N)+1.25P+2.91S+1.85Al+1.07V -------(C)
本発明の鋼線の製品では、マルテンサイト量は２５体積％以上、８５体積％未満が好ましい範囲である。
The amount of martensite (α ′) in the steel wire was determined by measuring the saturation magnetization value when a magnetic field of 10000 Oe was applied with a DC magnetometer, and using the following equations (A) to (C).
α ′ amount (vol.%) = σs / σs (bcc) × 100 ---------------- (A)
ss: Saturation magnetization value (T), ss (bcc): Saturation magnetization value when transformed to 100% α '(calculated value)
σs (bcc) = 2.14-0.030Creq ----------------- (B)
Creq = Cr + 1.8Si + Mo + 0.5Ni + 0.9Mn + 3.6 (C + N) + 1.25P + 2.91S + 1.85Al + 1.07V ------- (C)
In the steel wire product of the present invention, the martensite content is preferably 25% by volume or more and less than 85% by volume.
鋼線の疲労特性は、中村式の回転曲げ疲労試験にて、回転曲げ応力５００および６００Ｎ／ｍｍ2を負荷して１０5回の回転を負荷させて鋼線が破断するか否かで評価した。両応力とも破断しない場合を非常に良い（●），５００Ｎ／ｍｍ2のみ破断しない場合を良い（○），いずれも破断した場合を悪い（×）として評価した。本発明の範囲内であるＮｏ．１〜４２の鋼線の疲労特性は●または○であり、疲労特性に優れていた。特に、回転曲げ応力６００Ｎ／ｍｍ2で破断しないことは、ピアノ線相当以上の耐疲労特性を有することを示すものであり、従来ステンレス鋼線では難しいとされていたピアノ線代替として使用できる可能性のあるものである。そのため、産業上非常に有効である。
The fatigue characteristics of the steel wire were evaluated by whether or not the steel wire was broken by applying a rotational bending stress of 500 and 600 N / mm 2 and applying 10 5 rotations in a Nakamura-type rotary bending fatigue test. . The case where both stresses were not broken was evaluated as very good (●), the case where only 500 N / mm 2 was not broken was good (◯), and the case where both were broken was evaluated as bad (×). No. within the scope of the present invention. The fatigue characteristics of the
本発明例Ｎｏ．６，７，１０〜１５，２７，２８，比較例４８〜５３，６０，６１は、疲労強度に及ぼすＭｏ，Ａｌ量の影響を調査したもので、評価結果を図１に示す。本発明例は疲労強度に優れており、Ａｌ：０．５〜１．５％，Ｍｏ：０．５〜２．５％の範囲内では、疲労強度が特に優れている。 Invention Example No. 6, 7, 10 ～15,27,28, Comparative Example 48～53,60,61 is, Mo on the fatigue strength, which was to investigate the effect of Al content, and the evaluation results are shown in Figure 1. The examples of the present invention are excellent in fatigue strength, and the fatigue strength is particularly excellent in the range of Al: 0.5 to 1.5% and Mo: 0.5 to 2.5%.
また、本発明例Ｎｏ．１６〜２１，比較例Ｎｏ．７３〜７７は、疲労強度に及ぼすＮｇ値，Ｎ量の影響を調査したもので、評価結果を図２に示す。本発明例は疲労強度に優れており、Ｎｇ≧Ｎ，且つＮ：０．０３％以下の範囲内では、疲労強度が特に優れている。これらの結果から、ＡｌとＭｏが好適範囲内にあり、更にＮｇ値とＮ量の関係も好適な範囲内に制御した場合には、回転曲げ応力が６００Ｎ／ｍｍ2以上となり、産業上特に優れた効果を発揮することが分かる。 In addition, Invention Example No. 16-21, Comparative Example No. 73 to 77 are the results of investigating the effects of Ng value and N amount on fatigue strength, and the evaluation results are shown in FIG. The examples of the present invention are excellent in fatigue strength, and the fatigue strength is particularly excellent in the range of Ng ≧ N and N: 0.03% or less. From these results, when Al and Mo are within the preferable range, and the relationship between the Ng value and the N amount is also controlled within the preferable range, the rotational bending stress is 600 N / mm 2 or more, which is particularly excellent in the industry. It can be seen that the effect is exhibited.
一方、比較例Ｎｏ．４４〜８１は、成分が本発明から外れており、脱酸不良，耐食性不良や疲労特性に劣っていた。 On the other hand, Comparative Example No. Components Nos. 44 to 81 were out of the present invention and had poor deoxidation, poor corrosion resistance and fatigue properties.
耐食性は、鋼線の表層を#500で研磨後、ＪＩＳ Ｚ ２３７１の塩水噴霧試験に従い、１００時間噴霧試験を実施し、発銹するか否かで評価した。比較例Ｎｏ．４６は発銹しており耐食性が不良であった。その他の実施例については無発銹であり、問題なかった。 Corrosion resistance was evaluated by whether the surface layer of the steel wire was polished with # 500, followed by a spray test for 100 hours in accordance with the salt spray test of JIS Z 2371, and whether or not rusting occurred. Comparative Example No. No. 46 was moist and corrosion resistance was poor. Other examples were non-split and had no problems.
比較例Ｎｏ．８０，８１は、汎用の高純度フェライト系ステンレス鋼やオーステナイト系ステンレス鋼（ＳＵＳ３２１）について調査したもので、Ｎｇ値，Ｎの関係は満たすものの、その他の成分が満たしておらず、強度，マルテンサイト量が本発明範囲外であり、疲労強度に劣る。なお、これらの鋼では、Ａｌは脱酸のため添加され、ＴｉはＣ，Ｎを固定してＣｒ炭化物を防止し、Ｎは鋭敏化防止のために低減されるため、本発明の析出硬化および粗大窒化物防止して疲労強度を向上させる基本思想とは異なる。 Comparative Example No. 80 and 81 are surveys of general-purpose high-purity ferritic stainless steel and austenitic stainless steel (SUS321). The relationship between Ng value and N is satisfied, but other components are not satisfied, and the strength, martensite The amount is outside the range of the present invention, and the fatigue strength is inferior. In these steels, Al is added for deoxidation, Ti fixes C and N to prevent Cr carbide, and N is reduced to prevent sensitization. This is different from the basic idea of improving the fatigue strength by preventing coarse nitrides.
次に、本発明の（８）に記載の時効温度の影響について示す。 Next, the influence of the aging temperature described in (8) of the present invention will be shown.
表１−１のＡ，Ｅ鋼を、前記００４９段落に記載の方法でφ１．５ｍｍまで冷間で伸線加工を施し、最後に２５０〜７００℃，３０分の時効処理を行い、時効温度の影響を評価した。その評価結果を表３に示す。 The steels A and E in Table 1-1 were subjected to cold drawing to φ1.5 mm by the method described in the above paragraph 0049, and finally an aging treatment was performed at 250 to 700 ° C. for 30 minutes. The impact was evaluated. The evaluation results are shown in Table 3.
参考例Ｎｏ．１，５，８２〜８５では、３００〜６００℃で時効処理が施されており、２０００Ｎ／ｍｍ２を超える引張強さを示し，疲労特性に優れていた。一方、比較例Ｎｏ．８６〜９１では、時効処理温度が本発明範囲外であり、引張強さや疲労特性に劣っていた。 Reference Example No. In 1, 5, 82 to 85, aging treatment was performed at 300 to 600 ° C., the tensile strength exceeding 2000 N / mm 2 was exhibited, and the fatigue characteristics were excellent. On the other hand, Comparative Example No. In 86 to 91, the aging treatment temperature was outside the range of the present invention, and the tensile strength and fatigue characteristics were inferior.
次に、本発明の（９）に記載の時効処理の雰囲気の影響について示す。 Next, the influence of the aging treatment atmosphere described in (9) of the present invention will be described.
表１−１のＢ，Ｄ鋼を、前記００４９段落に記載の方法でφ１．５ｍｍまで冷間で伸線加工を施し、最後に大気又は無酸化の窒素雰囲気中で４５０℃，３０分の時効処理を行い、雰囲気の影響を評価した。その評価結果を表４に示す。 The steels B and D in Table 1-1 were subjected to cold drawing to φ1.5 mm by the method described in the above paragraph 0049, and finally aging at 450 ° C. for 30 minutes in an air or non-oxidizing nitrogen atmosphere. The treatment was performed and the influence of the atmosphere was evaluated. The evaluation results are shown in Table 4.
参考例Ｎｏ．９２〜９５では、窒素雰囲気で時効処理を施すことで、表面圧縮残留応力になるため疲労特性が向上しており、窒素雰囲気中の時効処理は疲労特性に有効である。 Reference Example No. In Nos. 92 to 95, aging treatment in a nitrogen atmosphere results in surface compressive residual stress, so fatigue characteristics are improved, and aging treatment in a nitrogen atmosphere is effective for fatigue characteristics.
以上の各実施例から明らかなように、本発明により、耐疲労特性に優れた高強度・高耐食性製品用の析出硬化型の準安定オーステナイト系ステンレス鋼線材，鋼線等を安価に製造でき、製品加工後に析出硬化処理を施すことで２０００Ｎ／ｍｍ2以上の強度に加え、優れた耐疲労特性を付与すること可能であり、軽量化・耐久性に優れる製品を安価に提供することができ、産業上極めて有用である。 As is clear from the above examples, according to the present invention, precipitation hardening type metastable austenitic stainless steel wire, steel wire, etc. for high strength and high corrosion resistance products having excellent fatigue resistance can be produced at low cost. In addition to the strength of 2000 N / mm 2 or more by performing precipitation hardening treatment after product processing, it is possible to provide excellent fatigue resistance properties, and it is possible to provide a product with excellent weight reduction and durability at a low cost. It is extremely useful in industry.
Claims (10)
Ｃ：０．０２〜０．１５％、
Ｓｉ：０．１〜４．０％、
Ｍｎ：０．１〜１０．０％、
Ｎｉ：３．０〜９．０％、
Ｃｒ：１３．０〜１９．０％、
Ｍｏ：０．８超〜4．０％、
Ａｌ：０．３５〜３．０％、
Ｔｉ：０．０１〜０．２０％、
Ｎ：０．０５％以下、
Ｏ：０．００４％以下を含有し、残部Ｆｅおよび不可避的不純物からなり、
下記（a）式で表されるＭｄ30値が−１０〜７０であり、下記(b)式で規定されるＮg値がＮ含有量以上、０．１０以下であり、引張強さが２０００Ｎ／ｍｍ２以上であることを特徴とする耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。
Ｍｄ30＝５５１−４６２（Ｃ＋Ｎ）−９．２Ｓｉ―８．１Ｍｎ
―２９（Ｎｉ＋Ｃｕ）−１３．７Ｃｒ―１８．５Ｍｏ・・・・・（a）
Ｎg＝0.002／（Ａｌ×Ｔｉ） ・・・・・（b） % By mass
C: 0.02 to 0.15%,
Si: 0.1 to 4.0%,
Mn: 0.1 to 10.0%
Ni: 3.0-9.0%,
Cr: 13.0 to 19.0%,
Mo: more than 0.8 to 4.0%,
Al: 0.35-3.0%,
Ti: 0.01-0.20%,
N: 0.05% or less,
O: 0.004% or less, the balance Fe and unavoidable impurities,
The Md30 value represented by the following formula (a) is -10 to 70, the Ng value defined by the following formula (b) is N content or more and 0.10 or less, and the tensile strength is 2000 N / mm. A precipitation hardening type metastable austenitic stainless steel wire excellent in fatigue resistance, characterized by being 2 or more.
Md30 = 551-462 (C + N) -9.2Si-8.1Mn
-29 (Ni + Cu) -13.7Cr-18.5Mo (a)
Ng = 0.002 / (Al × Ti) (b)
Ｖ：０．０５〜２．０％、
Ｎｂ：０．０５〜２．０％、
Ｗ：０．０５〜２．０％、
Ｔａ：０．０５〜２．０％の内、１種類以上を含有することを特徴とする請求項１または２に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。 In addition,
V: 0.05-2.0%,
Nb: 0.05 to 2.0%,
W: 0.05-2.0%,
The precipitation hardening type metastable austenitic stainless steel wire excellent in fatigue resistance according to claim 1 or 2, characterized by containing at least one of Ta: 0.05 to 2.0%.
Ｃａ：０．０００５〜０．０１％、
Ｍｇ：０．０００５〜０．０１％、
ＲＥＭ：０．０００５〜０．０５％の内、１種類以上を含有することを特徴とする請求項１〜６のいずれか一項に記載の耐疲労性に優れた析出硬化型の準安定オーステナイト系ステンレス鋼線。 In addition,
Ca: 0.0005 to 0.01%,
Mg: 0.0005 to 0.01%,
The precipitation hardening type metastable austenite excellent in fatigue resistance according to any one of claims 1 to 6, characterized in that it contains one or more of REM: 0.0005 to 0.05%. Stainless steel wire.
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| KR20240055008A (en) * | 2021-12-06 | 2024-04-26 | 닛테츠 스테인레스 가부시키가이샤 | Austenitic stainless steel sheet, manufacturing method, and leaf spring |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| SE420623B (en) * | 1979-12-28 | 1981-10-19 | Fagersta Ab | AUSTENITIC, EXCEPTION CARDABLE STAINLESS CHROME-NICKEL ALUMINUM STEEL |
| SE8102015L (en) * | 1980-04-07 | 1981-10-08 | Armco Inc | FERRIT-FREE SEPARATION HARDENABLE STAINLESS STEEL |
| JP4078467B2 (en) * | 1998-05-01 | 2008-04-23 | マニー株式会社 | Surgical needle |
| JP2001131713A (en) * | 1999-11-05 | 2001-05-15 | Nisshin Steel Co Ltd | Ti-CONTAINING ULTRAHIGH STRENGTH METASTABLE AUSTENITIC STAINLESS STEEL AND PRODUCING METHOD THEREFOR |
| CN1263880C (en) * | 2002-05-08 | 2006-07-12 | 新日本制铁株式会社 | High strength stainless steel wire excellent in ductility-toughness and modulus of rigidity and method for production thereof |
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