JP2010070812A - Free-cutting austenitic stainless steel wire rod excellent in cold forgeability, and manufacturing method therefor - Google Patents
Free-cutting austenitic stainless steel wire rod excellent in cold forgeability, and manufacturing method therefor Download PDFInfo
- Publication number
- JP2010070812A JP2010070812A JP2008240098A JP2008240098A JP2010070812A JP 2010070812 A JP2010070812 A JP 2010070812A JP 2008240098 A JP2008240098 A JP 2008240098A JP 2008240098 A JP2008240098 A JP 2008240098A JP 2010070812 A JP2010070812 A JP 2010070812A
- Authority
- JP
- Japan
- Prior art keywords
- austenitic stainless
- cold forgeability
- steel wire
- cutting
- steel
- 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.)
- Withdrawn
Links
Images
Landscapes
- Heat Treatment Of Steel (AREA)
Abstract
Description
本発明は、冷間鍛造性と被削性に優れかつ環境に悪影響を与える重金属を使用しない環境にやさしいオーステナイト系ステンレス鋼とその製造方法に関するものであり、例えば、複雑な形状を有しこれまで、切削加工のみで加工を行っている精密部品などを冷間鍛造加工と切削加工をあわせて行うことにより、材料歩留よく加工することが可能なオーステナイト系ステンレス鋼およびその製造方法に関するものである。 The present invention relates to an environmentally friendly austenitic stainless steel that is excellent in cold forgeability and machinability and does not use heavy metals that adversely affect the environment, and a method for producing the same. The present invention relates to an austenitic stainless steel that can be processed with high material yield by performing cold forging and cutting together on precision parts that are processed only by cutting, and a method for manufacturing the same. .
オーステナイト系ステンレス鋼は加工性、耐食性などに優れた性質を有することから、様々な分野において広く使用されている。ネジ、ボルトなどの各種機器部品は一般に冷間鍛造によって成形加工して製造されることが多い。この冷間鍛造による方法は加工能率、歩留が高い利点を有するが、精密な加工精度に劣る。一方、複雑な形状を有する部品では、すべて切削加工で製造されている。切削加工による方法では複雑な形状への加工が可能であり、非常に精密な寸法精度を満足することができる利点があるものの、太い線径の材料から加工されるため材料歩留が悪いという欠点がある。 Austenitic stainless steel is widely used in various fields because it has excellent properties such as workability and corrosion resistance. In general, various equipment parts such as screws and bolts are generally manufactured by cold forging. This cold forging method has the advantage of high processing efficiency and yield, but is inferior in precise processing accuracy. On the other hand, all parts having complicated shapes are manufactured by cutting. The cutting method allows processing into complex shapes and has the advantage of satisfying very precise dimensional accuracy, but has the disadvantage of poor material yield because it is processed from a material with a large wire diameter. There is.
従来、冷間鍛造性を求められる製造方法ではＳＵＳＸＭ７（１７％Ｃｒ−９％Ｎｉ−３％Ｃｕ−低Ｃ、Ｎ系）が、被削性を求められる製造方法ではＳＵＳ３０３（１８％Ｃｒ−９％Ｎｉ−０．３％Ｓ）などが用いられてきた。 Conventionally, SUSXM7 (17% Cr-9% Ni-3% Cu-low C, N-based) is used in manufacturing methods that require cold forgeability, while SUS303 (18% Cr-9 is used in manufacturing methods that require machinability. % Ni-0.3% S) has been used.
冷間鍛造性に優れたＳＵＳＸＭ７は被削性が悪く、被削性の優れたＳＵＳ３０３は冷間鍛造性が悪いという相反する特徴を有している。従って、複雑な形状を有する部品では材料歩留が悪くても被削性の高い鋼を使用し、切削加工にて製造しているのが通常であった。 SUSXM7, which has excellent cold forgeability, has a conflicting characteristic that machinability is poor and SUS303, which has excellent machinability, has poor cold forgeability. Therefore, parts having a complicated shape are usually manufactured by cutting using steel having high machinability even if the material yield is low.
しかしながら、近年、複雑な形状を有する部品を歩留・生産性よく製造するために、耐食性、被削性を向上させたオーステナイト系ステンレス鋼が提案され、脱酸による介在物の形態を変えることで特性を改善することが提案されている（下記特許文献１〜４）。 However, in recent years, austenitic stainless steel with improved corrosion resistance and machinability has been proposed in order to produce parts with complex shapes with good yield and productivity, and by changing the form of inclusions by deoxidation It has been proposed to improve characteristics (Patent Documents 1 to 4 below).
特許文献１に記載された文献はステンレス鋼の被削性向上を耐食性の低下を伴うことなく実現させるため、Ｃa、Ａｌ、Ｏ量を規制することにより、酸化物系介在物をゲーレナイト（２ＣａＯ・Ａｌ２Ｏ３・ＳｉＯ２）系とし、被削性を向上させたことを特徴とするものである。 The document described in Patent Document 1 realizes the improvement of machinability of stainless steel without lowering the corrosion resistance. Therefore, by limiting the amount of Ca, Al, and O, the oxide inclusions are changed to gehlenite (2CaO · Al 2 O 3 · SiO 2 ) system and improved machinability.
特許文献２に記載された発明は耐食性を劣化させることなく被削性を向上させるために、耐食性の低下が少ないとされているＣａを添加し、また硬質な介在物であるＡｌ2Ｏ3の生成を可能な限り抑制し、鋼中の介在物をＣａＯ・ＳｉＯ２とＭｎＯ・ＳｉＯ２の複合体とすることで被削性、冷間加工性を向上させることを特徴とするものである。 In order to improve the machinability without deteriorating the corrosion resistance, the invention described in Patent Document 2 adds Ca, which is said to have a small decrease in corrosion resistance, and is made of Al 2 O 3 which is a hard inclusion. The production is suppressed as much as possible, and the inclusion in the steel is made of a composite of CaO · SiO 2 and MnO · SiO 2 to improve machinability and cold workability.
特許文献３に記載された発明はAl２O３の生成による工具寿命の低下の問題に対応するため、脱酸時にAlを使用せず、被削性を向上させることを特徴とするものである。 The invention described in Patent Document 3 is characterized by improving machinability without using Al at the time of deoxidation in order to cope with the problem of reduction in tool life due to generation of Al 2 O 3. .
特許文献４に記載された発明は硫化物が発銹や孔食の起点となり耐食性を悪化させることから、これらの硫化物を用いないで、被削性改善に有効なアノーサイト（ＣａＯ・Ａｌ２Ｏ３・２ＳｉＯ２）系の酸化物を生成させ被削性を改善し、また多量のＺｒなどを添加することにより炭化物を生成し、耐食性を改善したことを特徴とするものである。 In the invention described in Patent Document 4, sulfides are the starting point of cracking and pitting corrosion and deteriorate corrosion resistance. Therefore, anorsite (CaO · Al 2) effective for improving machinability without using these sulfides. It is characterized by improving the corrosion resistance by generating an O 3 .2SiO 2 ) -based oxide to improve machinability and adding a large amount of Zr or the like to generate carbides.
しかしながら、これまで、冷間鍛造性を付与させた環境に悪影響を与える重金属を使用しない環境にやさしいオーステナイト系ステンレス快削鋼は提案されていない。 However, so far, no environment-friendly austenitic stainless free-cutting steel has been proposed that does not use heavy metals that adversely affect the cold forgeability environment.
本発明の目的は、環境に悪影響を与える重金属（Ｐｂ、Ｂｉ、Ｓｅ、Ｔｅ）を使用しないで、冷間鍛造性の優れたオーステナイト系ステンレス快削鋼およびその製造方法を提供することで、これまで切削加工のみで行われてきた部品加工の歩留を向上させることにある。
本発明は前記課題を解決するためになされたもので、軟質の硫黄快削鋼の酸化物系介在物の組成をコントロールすることにより、酸化物と硫化物の複合介在物を形成させ、且つ、熱間圧延で介在物を分断して、硫化物の微細分散化を促進させることによって、冷間鍛造性を向上させようとした結果、冷間鍛造用ＳＵＳＸＭ７（１７％Ｃｒ−９％Ｎｉ−３％Ｃｕ−低Ｃ、Ｎ系）の微量S系を基本成分として、極微量のＡｌ、Ｃａ、Ｏの量を制御し、粗圧延から仕上げ圧延までの全熱間圧延工程での鋼材の最低温度、熱間圧延工程の減面率を制御することで、硫化物を中心とした介在物を著しく微細分散化でき、かつ引張強さを５２０ＭＰａ以下に軟質化することで、冷間鍛造性を付与させることを見出した。 The present invention was made in order to solve the above problems, and by controlling the composition of oxide inclusions in soft sulfur free-cutting steel, a composite inclusion of oxide and sulfide was formed, and As a result of trying to improve cold forgeability by dividing inclusions by hot rolling to promote fine dispersion of sulfide, SUSXM7 (17% Cr-9% Ni-3 for cold forging) % Cu-low C, N-based) S is the basic component, and the amount of Al, Ca, O is controlled in a very small amount, and the minimum temperature of the steel in the entire hot rolling process from rough rolling to finish rolling. By controlling the area reduction rate in the hot rolling process, inclusions centering on sulfides can be remarkably finely dispersed, and the tensile strength is softened to 520 MPa or less, thereby providing cold forgeability. I found out that
すなわち、本発明の要旨とするところは、特許請求の範囲に記載したとおりの下記内容である。 That is, the gist of the present invention is the following contents as described in the claims.
（１）質量%で、Ｃ≦０．０３０％、Ｓｉ：０．１〜２．０％、Ｍｎ０．１〜３．０％、Ｐ≦０．０５％、Ｓ：０．０１〜０．０４％、Ｎｉ：８．０〜１２．０％、Ｃｒ：１７．０〜２０．０％、Ｃｕ：１．０〜４．０％、Ｎ≦０．０３０％、Ａｌ：０．００２〜０．０１０％、Ｃａ：０．００１〜０．０１０％、Ｏ：０．００１〜０．０２０％、残部Ｆｅおよび不可避的不純物からなる鋼からなり、かつ、質量比で０．２５≦Ca/Al≦２．５０および０．１０≦Ca/O≦０．３０の条件を満たすことにより、低軟化点を有するCaO-SiO2-Al2O3系の酸化物と（Mn,Cr）Sの硫化物との複合介在物を形成することを特徴とする冷間鍛造性に優れるオーステナイト系ステンレス快削鋼線材。
（２）前記鋼は、ＭｎＯの酸化物を含有すること特徴とする（１）に記載の冷間鍛造性に優れるオーステナイト系ステンレス快削鋼線材。
（３）表層から深さ１ｍｍの間における長径２μｍ未満の硫化物、酸化物などの介在物数の割合が８０%以上であることを特徴とする（１）または（２）に記載の冷間鍛造性に優れるオーステナイト系ステンレス快削鋼線材。
（４）前記鋼は、質量％で、Ｂ≦０．０１０％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冷間鍛造性に優れるオーステナイト系ステンレス快削鋼線材。
（５）前記鋼は、質量％で、Mo≦３．０％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冷間鍛造性に優れるオーステナイト系ステンレス快削鋼線材。
(1)% by mass, C ≦ 0.030%, Si: 0.1 to 2.0%, Mn 0.1 to 3.0%, P ≦ 0.05%, S: 0.01 to 0.04 %, Ni: 8.0-12.0%, Cr: 17.0-20.0%, Cu: 1.0-4.0%, N ≦ 0.030%, Al: 0.002-0. 010%, Ca: 0.001 to 0.010%, O: 0.001 to 0.020%, made of steel consisting of the balance Fe and inevitable impurities, and 0.25 ≦ Ca / Al ≦ by mass ratio 2. By satisfying the conditions of 2.50 and 0.10 ≦ Ca / O ≦ 0.30, CaO—SiO 2 —Al 2 O 3 -based oxide having a low softening point and sulfide of (Mn, Cr) S An austenitic stainless free-cutting steel wire excellent in cold forgeability, characterized in that it forms a composite inclusion.
(2) The austenitic stainless free-cutting steel wire rod having excellent cold forgeability according to (1), wherein the steel contains an oxide of MnO.
(3) The cold according to (1) or (2), wherein the ratio of the number of inclusions such as sulfides and oxides having a major axis of less than 2 μm between the surface layer and a depth of 1 mm is 80% or more Austenitic stainless free-cutting steel wire with excellent forgeability.
(4) The austenitic stainless steel having excellent cold forgeability according to any one of (1) to (3), wherein the steel contains mass% and contains B ≦ 0.010%. Cutting wire rod.
(5) Austenitic stainless steel excellent in cold forgeability according to any one of (1) to (4), wherein the steel contains% by weight and Mo ≦ 3.0%. Cutting wire rod.
（６）前記鋼の引張強度（ＴＳ）が５２０ＭＰａ以下であることを特徴とする（１）〜（５）のいずれか一項に記載の冷間鍛造性に優れるオーステナイト系ステンレス快削鋼線材。
（７）（１）〜（６）のいずれか一項に記載のオーステナイト系ステンレス快削鋼線材の製造方法であって、粗圧延から仕上げ圧延までの線材圧延中の鋼材最低温度が、酸化物、硫化物の軟化点以上である１０００〜１２００℃の高温とし、且つ、熱間圧延工程の減面率を９８．０％以上の高減面率にすること特徴とする冷間鍛造性に優れるオーステナイト系ステンレス快削鋼線材の製造方法。
(6) The austenitic stainless free-cutting steel wire rod having excellent cold forgeability according to any one of (1) to (5), wherein the steel has a tensile strength (TS) of 520 MPa or less.
(7) The method for producing an austenitic stainless free-cutting steel wire according to any one of (1) to (6), wherein the minimum temperature of the steel during rolling from rough rolling to finish rolling is an oxide. Excellent cold forgeability, characterized by a high temperature of 1000 to 1200 ° C., which is higher than the softening point of sulfide, and a high area reduction ratio of 98.0% or more in the hot rolling process. A method for producing austenitic stainless free-cutting steel wire.
本発明による冷間鍛造性と被削性を併せ持つオーステナイト系ステンレス快削鋼およびその製造方法によれば冷間鍛造性と切削加工で効率よく部品加工が可能となり、部品加工の低コスト化の効果を発揮するなど、産業上有用な著しい効果を奏する。 According to the austenitic stainless free-cutting steel having both cold forgeability and machinability according to the present invention and its manufacturing method, it is possible to efficiently process parts by cold forgeability and cutting, and the effect of lowering the cost of parts processing It exerts a significant industrially useful effect.
以下に、先ず、本発明の請求項１記載の限定理由について説明する。下記の説明において、各成分の表示は質量％を示す。 Below, the reason for limitation of Claim 1 of this invention is demonstrated first. In the following description, the indication of each component indicates mass%.
Ｃ：≦０．０３０％
Ｃはオーステナイト安定化元素であるが多量に含有させると耐食性、冷間鍛造性、耐工具磨耗性が劣化するため上限を０．０３０％とした。また、Ｃは鋼の強度を確保するために０．００３％以上が好ましい。さらに好ましくは０．００５〜０．０１５％である。
C: ≦ 0.030%
C is an austenite stabilizing element, but if contained in a large amount, corrosion resistance, cold forgeability, and tool wear resistance deteriorate, so the upper limit was made 0.030%. C is preferably 0.003% or more in order to ensure the strength of the steel. More preferably, it is 0.005 to 0.015%.
Ｓｉ：０．１〜２．０％
Ｓｉは脱酸剤として作用し、耐酸化性を向上させるにも有効な元素であるので０．１％以上含有させるが、必要以上の含有は冷間鍛造性、耐工具磨耗性を劣化させるため２．０％を上限とした。好ましくは０．１〜０．４％である。
Si: 0.1 to 2.0%
Si acts as a deoxidizer and is an effective element for improving oxidation resistance. Therefore, Si is contained in an amount of 0.1% or more. However, excessive inclusion deteriorates cold forgeability and tool wear resistance. The upper limit was 2.0%. Preferably it is 0.1 to 0.4%.
Ｍｎ：０．１〜３．０％
本発明ではＭｎはＭｎＳとして被削性を向上させる効果があるため。０．１％以上含有させるが、過剰な含有は耐食性や靭性を低下させるためその上限を３．０％とした。好ましくは１．０〜２．５％である。
Mn: 0.1 to 3.0%
In the present invention, Mn has the effect of improving machinability as MnS. Although the content is 0.1% or more, an excessive content lowers the corrosion resistance and toughness, so the upper limit was made 3.0%. Preferably it is 1.0 to 2.5%.
Ｐ：０．０５％以下
Ｐは含有量が多いと熱間加工性を低下させるため０．０５％を上限とした。好ましくは０．０４％以下である。
P: 0.05% or less P has a maximum content of 0.05% because hot workability is lowered when the content is large. Preferably it is 0.04% or less.
S：０．０１〜０．０４％
Ｓは被削性を改善する元素であるため０．０１％以上含有させるが、大量に含有させると硫化物を中心とした介在物が粗大化し、冷間鍛造性が劣化する。そのため微量Ａｌ、Ｃａを添加（制御）して、被削性と冷間鍛造性を兼備させるために０．０１〜０．０４％の範囲とした。好ましくは０．０１５〜０．０３％である。
S: 0.01-0.04%
Since S is an element that improves machinability, it is contained in an amount of 0.01% or more. However, if it is contained in a large amount, inclusions centering on sulfides become coarse and cold forgeability deteriorates. Therefore, a small amount of Al and Ca are added (controlled) to make the range of 0.01 to 0.04% in order to combine machinability and cold forgeability. Preferably it is 0.015-0.03%.
図１に１７．５Cr−９．５Ni−３．０Cu−０．３Si−２．０Mn−０．００２Al−０．００３Ca−０．０１０N―０．０１０Oの成分系でSを変化させ、鋼材温度を圧延工程で最低となった鋼材温度を１０９０℃、減面率を９９．４％以上で製造し、引張強度を約480〜510MPaとした材料の限界据込率に及ぼすS量の影響を示す。限界据込率の測定方法は実施例の項で述べる。一般に限界据込率が８０％以上あればヘッダー加工など冷間鍛造において良好な作業性・生産性を示すことが知られている。図１から被削性を向上させる元素であるS量の増加によって冷間鍛造性が低下していることが分かる。また、０．０３％のＳ量の鋼にＣａ添加すると約８０％の限界据込率を示した。しかし、０．１５％のＳを含有した鋼ではＣａ添加による限界据込率の上昇は確認できなかった。この試験結果より、冷間鍛造性を高く保つためにはS量を制限する必要がある。従ってSの上限を０．０４％とした。 In FIG. 1, S is changed in the component system of 17.5Cr-9.5Ni-3.0Cu-0.3Si-2.0Mn-0.002Al-0.003Ca-0.010N-0.010O, and the steel material temperature is changed. The effect of the amount of S on the limit upsetting rate of a material produced at a steel material temperature of 1090 ° C., a reduction in area of 99.4% or more, and having a tensile strength of about 480 to 510 MPa is shown. The method for measuring the limit upsetting rate will be described in the section of Examples. Generally, it is known that if the limit upsetting ratio is 80% or more, good workability and productivity are exhibited in cold forging such as header processing. It can be seen from FIG. 1 that the cold forgeability is reduced by increasing the amount of S, which is an element that improves machinability. Further, when Ca was added to 0.03% S steel, a limit upsetting rate of about 80% was exhibited. However, in steel containing 0.15% S, an increase in the limit upsetting rate due to Ca addition could not be confirmed. From this test result, it is necessary to limit the amount of S in order to keep the cold forgeability high. Therefore, the upper limit of S is set to 0.04%.
Ｎｉ：８．０〜１２．０％
Ｎｉは耐食性を向上させるとともに、冷間加工性を改善させる元素である。そのため下限を８．０％とした。また、Ｎｉは高価な元素であるためにその上限を１２．０％とした。好ましくは９．０〜１１．０％である。
Ni: 8.0 to 12.0%
Ni is an element that improves corrosion resistance and cold workability. Therefore, the lower limit is set to 8.0%. Moreover, since Ni is an expensive element, the upper limit was made 12.0%. Preferably it is 9.0 to 11.0%.
Ｃｒ：１７．０〜２０．０％
Ｃｒは耐食性向上に有効な元素である。１７．０％以下では耐食性が悪くなり、多いとオーステナイト相が不安定となるため上限を２０．０％とした。好ましくは１７．０〜１９．０％である。
Cr: 17.0 to 20.0%
Cr is an element effective for improving corrosion resistance. If it is 17.0% or less, the corrosion resistance deteriorates. If it is too much, the austenite phase becomes unstable, so the upper limit was made 20.0%. Preferably it is 17.0 to 19.0%.
Ｃｕ：１．０〜４．０％
Ｃｕはオーステナイト安定元素であり、冷間鍛造性を改善させる重要な元素である。そのためには少なくとも１．０％以上の添加が必要であるが、４．０％を超えて含有すると熱間加工性が悪化することから上限を４．０％とした。好ましくは２．０〜４．０％である。
Cu: 1.0-4.0%
Cu is an austenite stable element and is an important element for improving cold forgeability. For that purpose, addition of at least 1.0% is necessary, but if the content exceeds 4.0%, the hot workability deteriorates, so the upper limit was made 4.0%. Preferably it is 2.0 to 4.0%.
Ｎ：０．０３０％以下
Ｎは固溶作用によって冷間鍛造性を低下させる元素であるため、できる限り低下させることが望ましく、上限を０．０３０％とした。しかしながら低Ｎ量化は製造コストを増加させるため０．０１％以上が好ましい。さらに好ましくは０．０１０〜０．０１５％である。
N: 0.030% or less Since N is an element that lowers the cold forgeability by the solid solution action, it is desirable to reduce it as much as possible, and the upper limit was made 0.030%. However, lowering the N content increases the production cost, so 0.01% or more is preferable. More preferably, it is 0.010 to 0.015%.
Ａｌ：０．００２〜０．０１％
Ａｌは脱酸剤として作用するとともに、後述の低軟化点を有するCaO-SiO2-Al2O3-MnO系の介在物を生成し、硫化物との複合介在物とさせ、介在物の微細分散に重要な元素であるが、多量に含有すると硬質な粗大非金属介在物として存在するために冷間鍛造性を低下させる。そこで、その範囲を０．００２〜０．０１％とした。好ましくは０．００２〜０．００５％である。
Al: 0.002 to 0.01%
Al is acts as a deoxidizer, and generates a CaO-SiO 2 -Al 2 O 3 -MnO -based inclusions having a low softening point below, is a composite inclusions and sulfide, the inclusions fine Although it is an element important for dispersion, when it is contained in a large amount, it exists as a hard coarse non-metallic inclusion, so that cold forgeability is lowered. Therefore, the range was made 0.002 to 0.01%. Preferably it is 0.002 to 0.005%.
Ｃａ：０．００１〜０．０１％
Ｃａは低軟化点のCaO-SiO2-Al2O3系の酸化物を生成させるのに重要な元素である。Aｌ、Ｓｉなどの脱酸元素とOの微妙なコントロールにより後述する低融点のCaO-SiO2-Al2O3系酸化物を生成し、硫化物との複合介在物として、硫化物を微細に分散させる。これらの効果を得るためには少なくとも０．００１％以上の添加が必要である。しかし、多量に含有させると、これらの効果が得られなくなることに加え、製造性も低下することから、その上限を０．０１％とした。好ましくは０．００１〜０．００５％である。
Ca: 0.001 to 0.01%
Ca is an important element for forming a CaO—SiO 2 —Al 2 O 3 oxide having a low softening point. By the fine control of deoxidation elements such as Al and Si and O, the low-melting point CaO-SiO 2 -Al 2 O 3 oxide described later is generated, and the sulfide is finely formed as a complex inclusion with sulfide. Disperse. In order to obtain these effects, addition of at least 0.001% is necessary. However, if contained in a large amount, these effects cannot be obtained, and the manufacturability also decreases. Therefore, the upper limit was made 0.01%. Preferably it is 0.001 to 0.005%.
Ｏ：０．００１〜０．０２０％
ＯはAl、Caと同じく、CaO-SiO2-Al2O3系酸化物となり、硫化物との複合介在物として、微細に分散させるため、Ｏの含有は必須である。０．００１％未満ではその効果は小さく、０．０２０％を超えると硬質のＣｒ２Ｏ３が増大して冷間鍛造性及び被削性を低下させるので、その範囲を０．００１〜０．０２０％とした。好ましくは０．００５〜０．０１５％である。
O: 0.001 to 0.020%
O, like Al and Ca, becomes a CaO—SiO 2 —Al 2 O 3 -based oxide and is finely dispersed as a composite inclusion with a sulfide, so the inclusion of O is essential. If it is less than 0.001%, the effect is small, and if it exceeds 0.020%, hard Cr 2 O 3 is increased and cold forgeability and machinability are lowered. 020%. Preferably it is 0.005 to 0.015%.
質量比で０．２５≦Ca/Al≦２．５０
CaO-SiO2-Al2O3系の酸化物を生成させ、介在物をCa系の酸化物と（Mn,Cr）Sの硫化物の複合介在物とするためにはCa/Al量をコントロールすることが必要である。Ca/Al量が０．２５未満であると、CaO量が少なくなり、SiO2-Al2O3系の酸化物が多く存在し、複合介在物になりにくくなる。また、Ca/Al量が２．５０以上であると、２CaO・SiO2が多く生成され、複合介在物になりにくくなることに加え、鋳造時にノズルが溶損し、製造性に問題が発生するため、質量比で０．２５≦Ca/Al≦２．５とした。
0.25 ≦ Ca / Al ≦ 2.50 by mass ratio
In order to generate CaO-SiO 2 -Al 2 O 3 type oxides and to make inclusions complex inclusions of Ca type oxides and (Mn, Cr) S sulfides, the amount of Ca / Al is controlled. It is necessary to. When the Ca / Al content is less than 0.25, the CaO content decreases, and a large amount of SiO 2 —Al 2 O 3 oxide is present, making it difficult to form composite inclusions. Also, if the Ca / Al content is 2.50 or more, 2CaO · SiO 2 is produced in large amounts, making it difficult to form composite inclusions, and the nozzle melts during casting, causing problems in manufacturability. The mass ratio was 0.25 ≦ Ca / Al ≦ 2.5.
質量比で０．１０≦Ca/O≦０．３０
Ca/OについてもCaO-SiO2-Al2O3系を生成させ、介在物をCa系の酸化物と（Mn,Cr）Sの硫化物の複合介在物とするためにコントロールすることが重要である。Ca/O量が０．１０未満であると、SiO2-MnO-Cr2O3系の介在物が多くなり、CaO-SiO2-Al2O3系の介在物が少なくなり、複合介在物が生成しにくくなる。また０．３０以上であると、MnO量が減少し、複合介在物を生成しにくくなるとともに、鋳造時にノズルが溶損し、製造性に問題が発生するため、質量比で０．１０≦Ca/Al≦０．３０とした
0.10 ≦ Ca / O ≦ 0.30 in mass ratio
It is important to control Ca / O in order to form CaO-SiO 2 -Al 2 O 3 system and to make inclusions complex inclusions of Ca-based oxides and (Mn, Cr) S sulfides. It is. When the Ca / O amount is less than 0.10, the inclusion of SiO 2 —MnO—Cr 2 O 3 increases, the inclusion of CaO—SiO 2 —Al 2 O 3 decreases, and the composite inclusion Is difficult to generate. On the other hand, if it is 0.30 or more, the amount of MnO decreases, it becomes difficult to produce composite inclusions, and the nozzle melts during casting, causing problems in manufacturability, so that the mass ratio is 0.10 ≦ Ca / Al ≦ 0.30
CaO-SiO2-Al2O3系酸化物
極微量のＡｌ、Ｏ、Ｃａをコントロールすることにより、CaO-SiO2-Al2O3系の介在物が生成し（Mn,Cr）S系の硫化物の接種核として働き、複合介在物として、硫化物を微細に分散させる。また、これらの酸化物の軟化点１０５０〜１２００℃であることを見出した。これらの効果を得るためには、各元素の酸化物は少なくとも３ｍａｓｓ％以上含有することが必要である。また、好ましくは、CaO-SiO2-Al2O3-MnO系の酸化物にすることが好ましく、ＭｎＯが１ｍａｓｓ％以上含有することが必要である。さらに熱間圧延工程で圧延温度が最低となる鋼材温度を酸化物の軟化点以上である１０５０℃以上の高温で圧延し、熱間圧延の減面率を９８．０％以上の高減面率にすることで、これらの低軟化点の介在物が分断され微細分散する。硫化物の微細分散化により、冷間鍛造性向上につながる。
CaO-SiO 2 -Al 2 O 3 oxides By controlling trace amounts of Al, O, and Ca, inclusions of CaO-SiO 2 -Al 2 O 3 are generated (Mn, Cr) S Acts as a seed for sulfide inoculation and finely disperses sulfide as a composite inclusion. Moreover, it discovered that it was 1050-1200 degreeC of softening points of these oxides. In order to obtain these effects, it is necessary to contain at least 3 mass% of the oxide of each element. In addition, a CaO—SiO 2 —Al 2 O 3 —MnO-based oxide is preferably used, and MnO needs to be contained in an amount of 1 mass% or more. Furthermore, the steel material temperature at which the rolling temperature becomes the lowest in the hot rolling process is rolled at a high temperature of 1050 ° C. or higher, which is higher than the softening point of the oxide, and the hot rolling area reduction rate is 98.0% or higher. By doing so, these inclusions having a low softening point are divided and finely dispersed. The fine dispersion of sulfides improves cold forgeability.
本発明の請求項３記載の限定理由について述べる。 The reason for limitation according to claim 3 of the present invention will be described.
表層から深さ１ｍｍの間における長径２μｍ未満の硫化物、酸化物などの介在物数の割合が８０%以上
図２にS量を０．０３％と同レヘ゛ル、引張強度を約480〜510MPaとした材料における2μｍ未満の硫化物、酸化物などの介在物数の割合と限界据込率の関係を示す。硫化物の大きさとその数についての測定方法は実施例の項で述べる。介在物は加工時に破壊の起点となりやすいため、その大きさは非常に重要である。また、表層から深さ１ｍｍの間は加工時に応力の集中が大きいため、今回は表層から深さ１ｍｍの間の硫化物、酸化物などの介在物の大きさとその数を測定した。２μｍ未満の介在物数の割合が少なくなるほど冷間鍛造性が低下していることがわかる。すなわち硫化物、酸化物などの介在物の微細分散により、冷間鍛造性の向上が見られる。一般に限界据込率が８０％以上あればヘッダー加工など冷間鍛造において良好な作業性・生産性を示すことが知られており、８０％以上の限界据込率を確保するためは長径が２μm未満の硫化物、酸化物などの介在物数の割合が８０％以上必要であるため、この値とした。
The ratio of the number of inclusions such as sulfides and oxides with a major axis of less than 2 μm between the surface and the depth of 1 mm is 80% or more. In FIG. 2, the amount of S is 0.03%, the same level, and the tensile strength is about 480 to 510 MPa. The relationship between the ratio of the number of inclusions such as sulfides and oxides less than 2 μm and the limit upsetting rate in the obtained materials is shown. Measurement methods for the size and number of sulfides are described in the Examples section. The size of the inclusion is very important because it tends to be a starting point of fracture during processing. Moreover, since stress concentration is large during processing from the surface layer to a depth of 1 mm, the size and number of inclusions such as sulfides and oxides from the surface layer to a depth of 1 mm were measured this time. It can be seen that the cold forgeability decreases as the ratio of the number of inclusions less than 2 μm decreases. That is, cold forgeability is improved by fine dispersion of inclusions such as sulfides and oxides. Generally, it is known that if the limit upsetting rate is 80% or more, it shows good workability and productivity in cold forging such as header processing, and the major axis is 2μm to ensure the limit upsetting rate of 80% or more. Since the ratio of inclusions such as less than sulfides and oxides is required to be 80% or more, this value was used.
本発明の請求項４記載の限定理由について述べる。 The reason for limitation according to claim 4 of the present invention will be described.
Ｂ：≦０．０1０％
Bは熱間加工性や軟質化を改善するために添加される元素であり、０．００２％以上の添加により安定した効果が得られる。しかし過剰に添加するとBの化合物が析出し、熱間加工性を劣化させるので、その上限を０．０１０％とした。好ましくは０．００２〜０．００４％である。
B: ≦ 0.010%
B is an element added to improve hot workability and softening, and a stable effect can be obtained by adding 0.002% or more. However, if added in excess, the B compound precipitates and deteriorates hot workability, so the upper limit was made 0.010%. Preferably it is 0.002 to 0.004%.
本発明の請求項５記載の限定理由について述べる。 The reason for limitation according to claim 5 of the present invention will be described.
Ｍｏ：≦３．０％
ＭｏはＣｒと同様に耐食性を向上させるのに有効な元素であり０．１％以上の添加により安定した効果が得られる。しかし、多量に添加させると熱間加工性が低下するために上限を３．０％とした。好ましくは０．１〜２．５％である。
Mo: ≦ 3.0%
Mo is an element effective for improving the corrosion resistance like Cr, and a stable effect can be obtained by addition of 0.1% or more. However, the hot workability is lowered when a large amount is added, so the upper limit was made 3.0%. Preferably it is 0.1 to 2.5%.
本発明の請求項６記載の限定理由について述べる。 The reason for limitation according to claim 6 of the present invention will be described.
引張強度≦５２０ＭＰａ
図３にS量を約０．０３％とし、Ｃ，Ｎ量を変化させた材料の限界据込率に及ぼす引張強度の影響を示す。図３から引張強度（ＴＳ）の上昇によって冷間鍛造性が低下していることが分かる。この試験結果より、冷間鍛造性を高く保つためには引張強度を制限する必要がある。従って引張強度の上限を５２０ＭＰａとした。
Tensile strength ≦ 520MPa
FIG. 3 shows the influence of the tensile strength on the limit upsetting rate of a material in which the S amount is about 0.03% and the C and N amounts are changed. It can be seen from FIG. 3 that the cold forgeability is lowered due to the increase in tensile strength (TS). From this test result, it is necessary to limit the tensile strength in order to keep the cold forgeability high. Therefore, the upper limit of the tensile strength was set to 520 MPa.
本発明の請求項７記載限定理由について述べる。 The reason for limitation of claim 7 of the present invention will be described.
粗圧延から仕上げ圧延までの全熱間圧延工程でのる鋼材表面の最低温度を１０００℃〜１２００℃
圧延温度は硫化物の更なる微細分散化に重要な因子である。鋼材の温度は表面温度が最も低く、またその鋼材の表面温度は加熱後、粗圧延、中間圧延工程にかけて次第に低下し、中間圧延工程付近で全工程の最低温度（通常850〜950℃）となる。その後、線材径が小さくなるにつれ、圧延速度が上昇し、それに伴い加工発熱が発生しにて温度が上昇する温度経過を示す。本発明では、高温加熱、IH、中間保定炉、保熱カバー、高速圧延化を行うことにより、圧延工程における粗圧延から中間圧延までの温度低下を少なくし、中間圧延後での鋼材温度を１０００℃〜１２００℃高温での恒温圧延を実施している。圧延工程中の鋼材の表面温度が低いとＣａ系酸化物の軟化点温度以下となり分断しにくく、酸化物の分断による介在物の微細分散化が困難になるため１０００℃以上とした。また、１２００℃以上では粒界溶融による脆化や有害元素の完全固溶・再析出による脆化が生じやすくなるため上限を１２００℃とした。好ましくは１０５０℃〜１２００℃である。
Minimum temperature of steel surface in all hot rolling processes from rough rolling to finish rolling is 1000 ° C to 1200 ° C
The rolling temperature is an important factor for further fine dispersion of sulfides. The surface temperature of the steel material is the lowest, and the surface temperature of the steel material gradually decreases after heating through the rough rolling and intermediate rolling processes, and reaches the lowest temperature (usually 850 to 950 ° C) of all processes in the vicinity of the intermediate rolling process. . Thereafter, as the wire diameter becomes smaller, the rolling speed increases, and the temperature rises due to the generation of processing heat. In the present invention, by performing high temperature heating, IH, intermediate holding furnace, heat insulating cover, high speed rolling, the temperature drop from rough rolling to intermediate rolling in the rolling process is reduced, and the steel material temperature after intermediate rolling is 1000 C. to 1200.degree. C. at a high temperature. If the surface temperature of the steel material during the rolling process is low, the temperature becomes lower than the softening point temperature of the Ca-based oxide, and it is difficult to divide, and it becomes difficult to finely disperse inclusions by dividing the oxide. At 1200 ° C. or higher, embrittlement due to grain boundary melting and embrittlement due to complete solid solution / reprecipitation of harmful elements tend to occur, so the upper limit was set to 1200 ° C. Preferably it is 1050 degreeC-1200 degreeC.
熱間圧延の減面率を９８．０％以上
熱間圧延の減面率は硫化物の微細分散化に重要な因子である。減面率は{１−（熱間圧延後の断面積）/（鋳片の断面積）}×１００（％）で表せ、減面率が小さいと鋼中のCa系酸化物、硫化物の分断が起こりにくく、微細化が困難である。本開発において９８．０％以上の減面率があれば効率よく分断され、硫化物の微細分散化が可能であることを見出した。
The reduction in hot rolling is 98.0% or more. The reduction in hot rolling is an important factor for fine dispersion of sulfides. The area reduction rate can be expressed as {1- (cross-sectional area after hot rolling) / (cross-sectional area of slab)} × 100 (%). If the area reduction is small, the Ca-based oxides and sulfides in the steel Cutting is difficult to occur and miniaturization is difficult. In this development, it was found that if the area reduction rate was 98.0% or more, it was efficiently divided and fine dispersion of sulfides was possible.
以下に本発明の実施例について説明する。 Examples of the present invention will be described below.
表1、２に本発明の実施例の化学成分と冷間鍛造性、被削性（切屑処理性、耐工具磨耗性）および引張強度の評価結果を示す。 Tables 1 and 2 show the evaluation results of the chemical components, cold forgeability, machinability (chip treatability, tool wear resistance) and tensile strength of the examples of the present invention.
これら化学成分の鋼は１００ｋｇ真空溶解炉にてφ１８０ｍｍ角の鋳片に鋳込み、その後、最低鋼材表面温度を９９０〜１２1０℃、減面率を９７．５〜９９．７％で熱間圧延を行い、１０５０℃（オーステナイト系ステンレス鋼線で組織を安定化させる温度）で溶体化処理を施し、棒鋼サンプルを製造した。その後、冷間鍛造性、被削性（切屑処理性、耐工具磨耗性）および引張強度を調査した。 Steels of these chemical components are cast into φ180 mm square slabs in a 100 kg vacuum melting furnace, and then hot rolled at a minimum steel surface temperature of 990 to 1210 ° C. and a reduction in area of 97.5 to 99.7%. A solution treatment was performed at 1050 ° C. (temperature at which the structure was stabilized with an austenitic stainless steel wire) to produce a steel bar sample. Thereafter, cold forgeability, machinability (chip disposal, tool wear resistance) and tensile strength were investigated.
冷間鍛造性は圧縮試験によって得られる限界据込率によって評価した。圧縮試験は直径１１ｍｍの線材から高さ１２ｍｍ、直径８ｍｍの円柱状の試験片を作製して供試材とし、同心円状の溝をもつ拘束型ダイスでの圧縮試験により評価した。試験片の初期の高さをH０、割れが発生した圧縮後の高さをHとし以下の式で求めた値を限界据込率とした。
（1−H／H０）×１００（％）
圧縮試験機によって一定速度で試験片を圧縮し、試験片側面の割れの有無を目視で判定し、限界据込率によって大小で評価した。
本発明鋼Ｎｏ．1〜１８は限界据込率が８０％以上であった。
Cold forgeability was evaluated by the limit upsetting rate obtained by the compression test. In the compression test, a cylindrical test piece having a height of 12 mm and a diameter of 8 mm was prepared from a wire material having a diameter of 11 mm as a test material, and evaluation was performed by a compression test with a constraining die having concentric grooves. The initial height of the test specimen H 0, and the value determined height after compression cracks occur in and following equations H and the limit upsetting ratio.
(1−H / H 0 ) × 100 (%)
The test piece was compressed at a constant speed with a compression tester, the presence or absence of cracks on the side of the test piece was visually judged, and the size was evaluated based on the limit upsetting rate.
Invention Steel No. 1 to 18 had a limit upsetting rate of 80% or more.
硫化物、酸化物などの介在物のサイズ及びその数の測定は、試験片のＬ断面について埋め込み・鏡面研磨を行ったものについて、表層から深さ１ｍｍの間を光学顕微鏡にて１画素０．１２５μｍ観察できるカメラを用いて４００倍で２５０視野観察し、確認された硫化物、酸化物などの介在物について圧延方向に平行の長さを測定し、その数の割合を求め評価した。
本発明鋼Ｎｏ．1〜１８は２μｍ以下の硫化物、酸化物の介在物数の割合が８０％以上であった。
The size and the number of inclusions such as sulfides and oxides were measured by embedding and mirror-polishing the L cross section of the test piece. Using a camera capable of observing 125 μm, 250 fields of view were observed at 400 times, and the lengths parallel to the rolling direction were measured for the confirmed inclusions such as sulfides and oxides, and the ratio of the number was obtained and evaluated.
Invention Steel No. 1 to 18 had a ratio of the number of inclusions of 2 μm or less of sulfide and oxide of 80% or more.
切削試験は直径２２ｍｍに熱間鍛伸した棒鋼を供試材として、超硬工具（Ｐ２０種）を用いて、切削速度（５０〜２００ｍ／ｍｉｎ）、切込み（０．１〜１．０ｍｍ）、送り速度（０．０１〜０．１ｍｍ／ｒｅｖ）で外周切削をおこなった。被削性の評価は切屑処理性、耐工具磨耗性にて評価した。 The cutting test uses a steel bar hot forged to a diameter of 22 mm as a test material, using a carbide tool (P20 type), cutting speed (50 to 200 m / min), cutting (0.1 to 1.0 mm), Peripheral cutting was performed at a feed rate (0.01 to 0.1 mm / rev). The machinability was evaluated based on chip disposal and tool wear resistance.
切屑処理性の評価は短く破損しているものおよび規則的ならせん状のものを○、無規則で長く繋がったものを×とした。これは、短く破損した切屑を排出するものは切削中に表面に疵をつける可能性が低いが、無規則で長く繋がった切屑は表面に疵をつけたり、工具に絡まったりするためである。本発明鋼は短く破損したものと規則的ならせん状の切屑が観察された。 In the evaluation of the chip disposability, the short-damaged and regular spiral-shaped ones were marked with ◯, and the ones that were irregularly connected for a long time were marked with ×. This is because chips that discharge short and broken chips are less likely to wrinkle the surface during cutting, but chips that are irregularly connected for a long time are wrinkled on the surface or entangled with the tool. The steel of the present invention was observed to be short and broken and regular spiral chips.
耐工具磨耗は約4000ｍ切削時の工具を観察して評価した。工具磨耗がないものは○、局所的に大きな工具磨耗が観察されるものを×とした。本発明鋼は一部微量の工具磨耗が観察されるものもあるが、大きな工具磨耗は観察されなかった。 Tool wear resistance was evaluated by observing the tool when cutting about 4000 m. The case where there was no tool wear was rated as ◯, and the case where large tool wear was observed locally was marked as x. Some of the steels of the present invention have a small amount of tool wear observed, but no significant tool wear was observed.
引張強度はＪＩＳ９号Ａ（Ｇ．Ｌ１００ｍｍ）を用いて試験を行い、引張強度を測定した。本発明鋼の引張強度は５２０ＭＰａ以下であった。 The tensile strength was tested using JIS No. 9A (G.L100 mm), and the tensile strength was measured. The tensile strength of the steel of the present invention was 520 MPa or less.
一方、比較例Ｎｏ．１９〜４８は本発明に比べ、冷間鍛造性、被削性（切屑処理性、耐工具磨耗性）、引張強度、２μm以下の硫化物の割合、熱間加工性、コスト、表面疵、鋳片脆化ノズル溶損のいずれかが劣っていた。 On the other hand, Comparative Example No. 19 to 48 are cold forgeability, machinability (chip disposal property, tool wear resistance), tensile strength, ratio of sulfide of 2 μm or less, hot workability, cost, surface flaw, casting compared to the present invention. Either one of the single embrittlement nozzles was damaged.
以上実施例から分かるように本発明例に優位性は明らかである。 As can be seen from the embodiments, the advantages of the present invention are clear.
以上に実施例から明らかなように、本発明により冷間鍛造性に優れるオーステナイト系ステンレス快削鋼およびその製造方法を提供することが可能であり、これまで切削加工のみで複雑な形状を製造していた部品を冷間鍛造と切削加工によって、材料歩留まり、生産性よく製造する上で極めて有用である。 As is apparent from the above examples, according to the present invention, it is possible to provide an austenitic stainless free-cutting steel excellent in cold forgeability and a method for producing the same. It is extremely useful for manufacturing the parts that have been produced by cold forging and cutting with high material yield and high productivity.
Claims (7)
Ｃ≦０．０３０％、
Ｓｉ：０．１〜２．０％、
Ｍｎ０．１〜３．０％、
Ｐ≦０．０５％、
Ｓ：０．０１〜０．０４％、
Ｎｉ：８．０〜１２．０％、
Ｃｒ：１７．０〜２０．０％、
Ｃｕ：１．０〜４．０％、
Ｎ≦０．０３０％、
Ａｌ：０．００２〜０．０１０％、
Ｃａ：０．００１〜０．０１０％、
Ｏ：０．００１〜０．０２０％、残部Ｆｅおよび不可避的不純物からなる鋼からなり、
かつ、質量比で０．２５≦Ca/Al≦２．５０および０．１０≦Ca/O≦０．３０の条件を満たすことにより、
低軟化点を有するCaO-SiO2-Al2O3系の酸化物と（Mn,Cr）Sの硫化物との複合介在物を形成することを特徴とする冷間鍛造性に優れるオーステナイト系ステンレス快削鋼線材。 % By mass
C ≦ 0.030%,
Si: 0.1 to 2.0%,
Mn 0.1-3.0%,
P ≦ 0.05%,
S: 0.01-0.04%,
Ni: 8.0 to 12.0%,
Cr: 17.0 to 20.0%,
Cu: 1.0-4.0%,
N ≦ 0.030%,
Al: 0.002 to 0.010%,
Ca: 0.001 to 0.010%,
O: 0.001 to 0.020%, made of steel consisting of the balance Fe and inevitable impurities,
And by satisfying the conditions of 0.25 ≦ Ca / Al ≦ 2.50 and 0.10 ≦ Ca / O ≦ 0.30 by mass ratio,
Austenitic stainless steel with excellent cold forgeability, characterized by forming composite inclusions of CaO-SiO 2 -Al 2 O 3 oxides with low softening point and sulfides of (Mn, Cr) S Free-cutting steel wire rod.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008240098A JP2010070812A (en) | 2008-09-19 | 2008-09-19 | Free-cutting austenitic stainless steel wire rod excellent in cold forgeability, and manufacturing method therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2008240098A JP2010070812A (en) | 2008-09-19 | 2008-09-19 | Free-cutting austenitic stainless steel wire rod excellent in cold forgeability, and manufacturing method therefor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2010070812A true JP2010070812A (en) | 2010-04-02 |
Family
ID=42202873
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2008240098A Withdrawn JP2010070812A (en) | 2008-09-19 | 2008-09-19 | Free-cutting austenitic stainless steel wire rod excellent in cold forgeability, and manufacturing method therefor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2010070812A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5224424B1 (en) * | 2012-05-07 | 2013-07-03 | 山陽特殊製鋼株式会社 | Steel with excellent rolling fatigue life |
| JP2018028146A (en) * | 2016-08-10 | 2018-02-22 | 新日鐵住金ステンレス株式会社 | Two-phase stainless steel for clad steel and clad steel |
| CN112251665A (en) * | 2020-09-28 | 2021-01-22 | 无锡市法兰锻造有限公司 | Austenitic stainless steel forging for ultralow-temperature liquid hydrogen container and manufacturing method thereof |
| CN113528963A (en) * | 2021-07-16 | 2021-10-22 | 浙江青山钢铁有限公司 | Free-cutting high-corrosion-resistance austenitic stainless steel wire rod and preparation method thereof |
| CN113528964A (en) * | 2021-07-16 | 2021-10-22 | 浙江青山钢铁有限公司 | Free-cutting high-surface-quality austenitic stainless steel wire and preparation method thereof |
| CN114453413A (en) * | 2022-01-12 | 2022-05-10 | 山东工业职业学院 | Rolling method of sulfur-containing free-cutting stainless steel wire rod |
| CN115466908A (en) * | 2022-09-29 | 2022-12-13 | 浙江青山钢铁有限公司 | Selenium-containing calcium-containing free-cutting stainless steel and preparation method thereof |
| CN115478202A (en) * | 2021-05-31 | 2022-12-16 | 宝武特种冶金有限公司 | Free-cutting austenitic stainless steel bar and preparation method thereof |
-
2008
- 2008-09-19 JP JP2008240098A patent/JP2010070812A/en not_active Withdrawn
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5224424B1 (en) * | 2012-05-07 | 2013-07-03 | 山陽特殊製鋼株式会社 | Steel with excellent rolling fatigue life |
| JP2018028146A (en) * | 2016-08-10 | 2018-02-22 | 新日鐵住金ステンレス株式会社 | Two-phase stainless steel for clad steel and clad steel |
| CN112251665A (en) * | 2020-09-28 | 2021-01-22 | 无锡市法兰锻造有限公司 | Austenitic stainless steel forging for ultralow-temperature liquid hydrogen container and manufacturing method thereof |
| CN115478202A (en) * | 2021-05-31 | 2022-12-16 | 宝武特种冶金有限公司 | Free-cutting austenitic stainless steel bar and preparation method thereof |
| CN113528963A (en) * | 2021-07-16 | 2021-10-22 | 浙江青山钢铁有限公司 | Free-cutting high-corrosion-resistance austenitic stainless steel wire rod and preparation method thereof |
| CN113528964A (en) * | 2021-07-16 | 2021-10-22 | 浙江青山钢铁有限公司 | Free-cutting high-surface-quality austenitic stainless steel wire and preparation method thereof |
| CN114453413A (en) * | 2022-01-12 | 2022-05-10 | 山东工业职业学院 | Rolling method of sulfur-containing free-cutting stainless steel wire rod |
| CN114453413B (en) * | 2022-01-12 | 2024-02-27 | 山东工业职业学院 | Rolling method of sulfur-containing free-cutting stainless steel wire rod |
| CN115466908A (en) * | 2022-09-29 | 2022-12-13 | 浙江青山钢铁有限公司 | Selenium-containing calcium-containing free-cutting stainless steel and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101830023B1 (en) | Spring steel and method for producing same | |
| JP4424503B2 (en) | Steel bar and wire rod | |
| JP2010070812A (en) | Free-cutting austenitic stainless steel wire rod excellent in cold forgeability, and manufacturing method therefor | |
| KR20200124294A (en) | Martensitic S free cutting stainless steel | |
| JP5142601B2 (en) | High hardness, non-magnetic free-cutting stainless steel | |
| JP6642237B2 (en) | Cold forging steel and method for producing the same | |
| JP5092578B2 (en) | Low carbon sulfur free cutting steel | |
| JPWO2014125770A1 (en) | Lead free cutting steel | |
| JP5474615B2 (en) | Martensitic stainless free-cutting steel bar wire with excellent forgeability | |
| JP5556778B2 (en) | Free-cutting steel for cold forging | |
| JP5474616B2 (en) | Ferritic stainless free-cutting steel rod with excellent forgeability | |
| JP7199231B2 (en) | Ferritic S free-cutting stainless steel | |
| JP4605695B2 (en) | Pre-hardened steel for die casting molds | |
| JP5583986B2 (en) | Austenitic stainless free-cutting steel rod with excellent forgeability | |
| JP5957241B2 (en) | Ferritic free-cutting stainless steel bar wire and method for producing the same | |
| JP4949100B2 (en) | Austenitic stainless free-cutting steel with excellent cold forgeability and machinability | |
| JP6776469B1 (en) | Duplex stainless steel and its manufacturing method | |
| JP4032915B2 (en) | Wire for machine structure or steel bar for machine structure and manufacturing method thereof | |
| JP2004292929A (en) | Steel for machine structural use | |
| JP2018131670A (en) | Ferritic free-cutting stainless wire | |
| KR20170121267A (en) | Hot rolled bar stock, manufacturing method of parts and hot rolled bar stock | |
| KR102226488B1 (en) | Cold forging steel and its manufacturing method | |
| JP2009215637A (en) | Case hardening steel having excellent machinability and crystal grain coarsening preventability | |
| JP2001152279A (en) | Free cutting steel | |
| JP2005290553A (en) | Steel plate excellent in machinability, toughness and weldability, and method for production thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20110513 |
|
| A761 | Written withdrawal of application |
Effective date: 20111129 Free format text: JAPANESE INTERMEDIATE CODE: A761 |