JP7121142B2 - Cr-based stainless steel sheet with excellent resistance to hydrogen embrittlement - Google Patents
Cr-based stainless steel sheet with excellent resistance to hydrogen embrittlement Download PDFInfo
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- JP7121142B2 JP7121142B2 JP2020561497A JP2020561497A JP7121142B2 JP 7121142 B2 JP7121142 B2 JP 7121142B2 JP 2020561497 A JP2020561497 A JP 2020561497A JP 2020561497 A JP2020561497 A JP 2020561497A JP 7121142 B2 JP7121142 B2 JP 7121142B2
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- stainless steel
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- based stainless
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- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims description 134
- 229910001220 stainless steel Inorganic materials 0.000 title claims description 54
- 239000010935 stainless steel Substances 0.000 title claims description 45
- 229910052739 hydrogen Inorganic materials 0.000 title description 101
- 239000001257 hydrogen Substances 0.000 title description 100
- 229910000831 Steel Inorganic materials 0.000 claims description 48
- 239000010959 steel Substances 0.000 claims description 48
- 239000013078 crystal Substances 0.000 claims description 23
- 238000005096 rolling process Methods 0.000 claims description 21
- 229910052719 titanium Inorganic materials 0.000 claims description 10
- 229910052796 boron Inorganic materials 0.000 claims description 9
- 229910052718 tin Inorganic materials 0.000 claims description 9
- 239000007769 metal material Substances 0.000 claims description 8
- 239000012535 impurity Substances 0.000 claims description 7
- 230000000694 effects Effects 0.000 description 19
- 239000000463 material Substances 0.000 description 15
- 238000005097 cold rolling Methods 0.000 description 12
- 229910052698 phosphorus Inorganic materials 0.000 description 11
- 238000011156 evaluation Methods 0.000 description 10
- 230000007423 decrease Effects 0.000 description 9
- 229910052758 niobium Inorganic materials 0.000 description 9
- 238000005204 segregation Methods 0.000 description 9
- 229910052717 sulfur Inorganic materials 0.000 description 9
- 238000005482 strain hardening Methods 0.000 description 8
- 238000012360 testing method Methods 0.000 description 8
- 230000007704 transition Effects 0.000 description 8
- 238000000034 method Methods 0.000 description 7
- 239000000203 mixture Substances 0.000 description 7
- 229910052750 molybdenum Inorganic materials 0.000 description 7
- 239000004033 plastic Substances 0.000 description 7
- 229910052761 rare earth metal Inorganic materials 0.000 description 7
- 230000009467 reduction Effects 0.000 description 7
- 238000009864 tensile test Methods 0.000 description 7
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 238000000137 annealing Methods 0.000 description 6
- 229910052802 copper Inorganic materials 0.000 description 6
- 239000000446 fuel Substances 0.000 description 6
- 229910052733 gallium Inorganic materials 0.000 description 6
- 238000005098 hot rolling Methods 0.000 description 6
- 230000003993 interaction Effects 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 229910052757 nitrogen Inorganic materials 0.000 description 6
- 238000007670 refining Methods 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 229910052726 zirconium Inorganic materials 0.000 description 6
- 229910045601 alloy Inorganic materials 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 5
- 230000006866 deterioration Effects 0.000 description 5
- 238000001887 electron backscatter diffraction Methods 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 229910052759 nickel Inorganic materials 0.000 description 5
- 229910052710 silicon Inorganic materials 0.000 description 5
- 229910052721 tungsten Inorganic materials 0.000 description 5
- 229910052720 vanadium Inorganic materials 0.000 description 5
- 229910052727 yttrium Inorganic materials 0.000 description 5
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 229910052787 antimony Inorganic materials 0.000 description 4
- 239000012298 atmosphere Substances 0.000 description 4
- 229910000963 austenitic stainless steel Inorganic materials 0.000 description 4
- 230000002542 deteriorative effect Effects 0.000 description 4
- 238000009792 diffusion process Methods 0.000 description 4
- 229910052735 hafnium Inorganic materials 0.000 description 4
- 229910052746 lanthanum Inorganic materials 0.000 description 4
- 229910052748 manganese Inorganic materials 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 229910000838 Al alloy Inorganic materials 0.000 description 3
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 239000011261 inert gas Substances 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000002791 soaking Methods 0.000 description 3
- 239000006104 solid solution Substances 0.000 description 3
- 238000007711 solidification Methods 0.000 description 3
- 230000008023 solidification Effects 0.000 description 3
- 229910000859 α-Fe Inorganic materials 0.000 description 3
- 229910000851 Alloy steel Inorganic materials 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- 238000005275 alloying Methods 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 2
- 230000033228 biological regulation Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 230000003749 cleanliness Effects 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 239000010960 cold rolled steel Substances 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000009863 impact test Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 150000001247 metal acetylides Chemical class 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 229910018125 Al-Si Inorganic materials 0.000 description 1
- 229910018520 Al—Si Inorganic materials 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 229910052684 Cerium Inorganic materials 0.000 description 1
- 229910052765 Lutetium Inorganic materials 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000003831 deregulation Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000002050 diffraction method Methods 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 229910001651 emery Inorganic materials 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 229910052747 lanthanoid Inorganic materials 0.000 description 1
- 150000002602 lanthanoids Chemical class 0.000 description 1
- OHSVLFRHMCKCQY-UHFFFAOYSA-N lutetium atom Chemical compound [Lu] OHSVLFRHMCKCQY-UHFFFAOYSA-N 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 229910001105 martensitic stainless steel Inorganic materials 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 238000004881 precipitation hardening Methods 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 229910052706 scandium Inorganic materials 0.000 description 1
- SIXSYDAISGFNSX-UHFFFAOYSA-N scandium atom Chemical compound [Sc] SIXSYDAISGFNSX-UHFFFAOYSA-N 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 150000003568 thioethers Chemical class 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
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Description
本発明は耐水素脆性に優れたＣｒ系ステンレス鋼板に関するものであり、特に、高圧水素ガス用機器の金属材料として好適なＣｒ系ステンレス鋼板に関する。 TECHNICAL FIELD The present invention relates to a Cr-based stainless steel sheet having excellent resistance to hydrogen embrittlement, and more particularly to a Cr-based stainless steel sheet suitable as a metal material for high-pressure hydrogen gas equipment.
近年、地球温暖化が一因となる異常気象から、二酸化炭素を主とする温室効果ガスの発生を抑制することが強く求められている。この一環として、燃料電池を電力源とする自動車や輸送機器の開発が進められている。燃料電池は水素を燃料として電力を発生させるため、二酸化炭素が発生せず、またエネルギー変換効率も高いので、有力な電力源と位置付けられている。 In recent years, due to abnormal weather caused by global warming, there is a strong demand to suppress the generation of greenhouse gases, mainly carbon dioxide. As part of this, the development of automobiles and transportation equipment that use fuel cells as power sources is underway. Since fuel cells generate electric power using hydrogen as fuel, they do not generate carbon dioxide and have high energy conversion efficiency, so they are positioned as a powerful power source.
水素を燃料とする燃料電池や、それに水素を供給するための水素ステーションを含む機器においては、構成部品が水素ガス環境に曝される。水素ガス環境に曝される金属材料では、材料内に侵入した水素によって引張強さや伸びあるいは絞りなどの機械的性質が低下する現象が知られている。これら現象は水素脆化と呼ばれている。このような水素脆化の問題から、日本自動車研究所技術標準ＪＡＲＩＳ００１では圧力３５ＭＰａの自動車用高圧水素容器に対して、またＫＨＫＳ０１２８では圧力７０ＭＰａの自動車用高圧水素容器に対して、いずれもオーステナイト系ステンレス鋼ＳＵＳ３１６Ｌとアルミ合金６０６１－Ｔ６の使用を規定している。 BACKGROUND OF THE INVENTION In a device including a fuel cell fueled by hydrogen and a hydrogen station for supplying hydrogen to the fuel cell, components are exposed to a hydrogen gas environment. It is known that metal materials exposed to a hydrogen gas environment have a phenomenon in which mechanical properties such as tensile strength, elongation, or reduction in area decrease due to hydrogen that has penetrated into the material. These phenomena are called hydrogen embrittlement. From such a problem of hydrogen embrittlement, JARIS001 of the Japan Automobile Research Institute technical standard for high-pressure hydrogen containers for automobiles with a pressure of 35 MPa, and KHKS0128 for high-pressure hydrogen containers for automobiles with a pressure of 70 MPa. It specifies the use of steel SUS316L and aluminum alloy 6061-T6.
一般高圧ガス保安規則の例示基準では、圧力２０ＭＰａ以上、圧力８２ＭＰａ以下の水素インフラ機器に対して、ＪＩＳ Ｇ ４３０４およびＪＩＳ Ｇ ４３０５に規定するオーステナイト系ステンレス鋼板（ＳＵＳ３１６とＳＵＳ３１６Ｌ）のＮｉ当量（Ｎｉ＋０．６５Ｃｒ＋０．９８Ｍｏ＋１．０５Ｍｎ＋０．３５Ｓｉ＋１２．６Ｃ）を高めた材料（例えばＮｉ当量≧２８．５）の使用を規定している。使用温度は－４５℃以上、２５０℃以下である。これらオーステナイト系ステンレス鋼において、例えば、特許文献１や特許文献２ではＳＵＳ３１６Ｌの強度上昇や高価なＭｏの低下による経済性を改良しようとしたステンレス鋼も開示されている。 According to the example standards of the General High-Pressure Gas Safety Regulations, the Ni equivalent (Ni+0. 65Cr + 0.98Mo + 1.05Mn + 0.35Si + 12.6C) is specified for use of materials (eg Ni equivalent ≥ 28.5). The operating temperature is -45°C or higher and 250°C or lower. Among these austenitic stainless steels, Patent Documents 1 and 2, for example, also disclose stainless steels intended to improve economic efficiency by increasing the strength of SUS316L and decreasing Mo, which is expensive.
前記した一般高圧ガス保安規則では、２０１６年の改正により圧力２０ＭＰａ以下の水素機器に対する材料規制が撤廃された。これら規制緩和に伴い、高圧水素ガス中においても経済性の高いステンレス鋼板の使用ニーズが益々高くなっており、多様な鋼材において高圧水素ガス中での耐水素脆性の評価が望まれている。フェライト系およびマルテンサイト系ステンレス鋼板（以下、総称して「Ｃｒ系ステンレス鋼板」という。）は、レアメタルであるＮｉを殆ど含まないことから、オーステナイト系ステンレス鋼板と比べて経済性に優れる。従来、例えば、非特許文献１ではステンレス鋼を含む鉄鋼材料全般を対象として、室温・高圧水素ガス中で評価した水素脆化特性が開示されている。代表的なオーステナイト系ステンレス鋼であるＳＵＳ３０４、及びＣｒ系ステンレス鋼は、水素脆化しやすいことが報告されている。そのため、一般的には圧力２０ＭＰａ程度の高圧水素ガス中においてもＳＵＳ３１６ＬやＳＵＳ３１６の使用を推奨している。さらに、体心立方構造を有するＣｒ系ステンレス鋼は面心立方構造のオーステナイト系ステンレス鋼と比べて、室温以下の低温で靭性が低下するという課題（低温脆性）もある。 In the General High-Pressure Gas Safety Regulations, the 2016 revision abolished material restrictions on hydrogen equipment with a pressure of 20 MPa or less. Along with these deregulations, the need to use highly economical stainless steel sheets even in high-pressure hydrogen gas is increasing, and evaluation of hydrogen embrittlement resistance in high-pressure hydrogen gas is desired for various steel materials. Ferritic and martensitic stainless steel sheets (hereinafter collectively referred to as "Cr-based stainless steel sheets") contain little Ni, which is a rare metal, and thus are more economical than austenitic stainless steel sheets. Conventionally, for example, Non-Patent Document 1 discloses hydrogen embrittlement characteristics evaluated in high-pressure hydrogen gas at room temperature for steel materials in general including stainless steel. It has been reported that SUS304, which is a representative austenitic stainless steel, and Cr-based stainless steel are susceptible to hydrogen embrittlement. Therefore, it is generally recommended to use SUS316L or SUS316 even in high-pressure hydrogen gas of about 20 MPa. Furthermore, Cr-based stainless steel having a body-centered cubic structure has a problem (low-temperature embrittlement) that its toughness is lowered at low temperatures below room temperature, compared to austenitic stainless steel having a face-centered cubic structure.
高圧水素ガス環境で使用できる材料の拡大を目的として、耐水素脆性に優れるＡｌまたはＡｌ合金で被覆した材料も考案されている。特許文献３には、ＡｌまたはＡｌ合金で被覆した高圧水素ガス用圧力容器と高圧水素ガス用配管が開示されている。実施例では、オーステナイト系ステンレス鋼とオーステナイト相を含む二相ステンレス鋼への皮膜付与を対象としており、水素脆化しやすい鋼材、例えばＣｒ系ステンレス鋼における皮膜形成や水素侵入特性は示されていない。 For the purpose of expanding the range of materials that can be used in high-pressure hydrogen gas environments, materials coated with Al or Al alloys, which are excellent in resistance to hydrogen embrittlement, have also been devised. Patent Document 3 discloses a high-pressure hydrogen gas pressure vessel and a high-pressure hydrogen gas pipe coated with Al or an Al alloy. In the examples, coatings are applied to austenitic stainless steels and duplex stainless steels containing an austenitic phase, and coating formation and hydrogen permeation characteristics in steel materials prone to hydrogen embrittlement, such as Cr-based stainless steels, are not shown.
また、特許文献４には、単体では水素脆化しやすい鋼材に対して、Ｓｉの添加量を１～５％としたＡｌ－Ｓｉ系合金を用いた溶融めっきを施し、これにより耐水素透過皮膜を形成した水素機器用の基材が開示されている。基材の鋼材は炭素鋼、低合金鋼、Ｃｒ系ステンレス鋼とし、水素脆化を防止し、併せて製作コストを低く抑えられるとしている。しかしながら、実施例は、ＳＵＳ３０４、ＳＵＳ６３０（１５Ｃｒ－４Ｎｉ－３Ｃｕ）並びにＳＣＭ４３５（低合金鋼）に限定されている。経済性の高いＣｒ系ステンレス鋼板に関しては、その水素脆化特性についてもその使用についても全く言及されていない。 Further, in Patent Document 4, hot-dip plating using an Al—Si-based alloy containing 1 to 5% Si is applied to a steel material that is prone to hydrogen embrittlement by itself, thereby forming a hydrogen permeation resistant coating. Substrates for formed hydrogen devices are disclosed. Carbon steel, low-alloy steel, or Cr-based stainless steel is used as the base material to prevent hydrogen embrittlement and to keep production costs low. However, the examples are limited to SUS304, SUS630 (15Cr-4Ni-3Cu) and SCM435 (low alloy steel). Regarding the highly economical Cr-based stainless steel sheet, neither its hydrogen embrittlement properties nor its use is mentioned at all.
前記した特許文献１～４に記載されたステンレス鋼はオーステナイト系と二相およびＳＵＳ６３０（析出硬化型）にとどまり、さらに非特許文献１に開示されたＣｒ系ステンレス鋼は水素脆化しやすく高圧水素ガス用途において使用する耐水素脆性を有するものではない。Ｃｒ系ステンレス鋼については、低温脆性の課題も有する。 The stainless steels described in Patent Documents 1 to 4 are limited to austenitic, two-phase, and SUS630 (precipitation hardening) types, and the Cr-based stainless steels disclosed in Non-Patent Document 1 are susceptible to hydrogen embrittlement and high-pressure hydrogen gas. It does not have hydrogen embrittlement resistance for use in applications. Cr-based stainless steel also has a problem of low-temperature embrittlement.
本発明は上記事情に鑑みてなされたものであり、高圧水素ガス中で使用するための耐水素脆性を備え、高圧水素ガス用機器の金属材料として好適な、耐水素脆性に優れたＣｒ系ステンレス鋼板を提供することを課題とする。併せて、耐低温脆性との両立を実現することを課題とする。 The present invention has been made in view of the above circumstances, and is equipped with hydrogen embrittlement resistance for use in high-pressure hydrogen gas, and is suitable as a metal material for high-pressure hydrogen gas equipment, Cr-based stainless steel excellent in hydrogen embrittlement resistance. An object is to provide a steel plate. At the same time, an object is to achieve compatibility with low-temperature embrittlement resistance.
上記課題を解決するため、本発明は以下の構成を採用する。
［１］質量％で、Ｃ：０．０２０％以下、Ｓｉ：１．００％以下、Ｍｎ：１．００％以下、Ｐ：０．０４０％以下、Ｓ：０．００３０％以下、Ｃｒ：１０．０～１８．０％、Ｎ：０．０２０％以下、Ａｌ：０．１０％以下、さらにＮｂ：０．５％以下、Ｔｉ：０．５％以下の１種または２種を含み、Ｓｎ：０～０．３％、Ｂ：０～０．００５％、Ｎｉ：０～１％、Ｃｕ：０～１％、Ｍｏ：０～１％、Ｓｂ：０．２％以下、Ｖ：０～０．５％、Ｗ：０～０．５％、Ｚｒ：０～０．５％、Ｃｏ：０～０．５％、Ｍｇ：０～０．００５％、Ｃａ：０～０．００５％、Ｇａ：０～０．０２０％、Ｌａ：０～０．１％、Ｙ：０～０．１％、Ｈｆ：０～０．１％、ＲＥＭ：０～０．１％、残部がＦｅおよび不純物からなり、板表面における集合組織が下記の（ｉ）および（ii）を満たすことを特徴とするＣｒ系ステンレス鋼板。
（ｉ）板表面における鋼板表面の法線方向と｛２１１｝面方位との角度差が１０°以内である結晶粒（以下「｛２１１｝±１０°方位粒」という。）の面積率が３０％未満
（ii）（ｉ）で定義した｛２１１｝±１０°方位粒において、圧延方向の長さおよび板幅方向の長さがいずれも平均で０．１５ｍｍ未満
［２］さらに質量％で、Ｓｎ：０．００１～０．３％、Ｂ：０．００５％以下を含有し、
下記（１）式を満たすことを特徴とする本発明のＣｒ系ステンレス鋼板。
Ｓｉ＋０．５Ｍｎ＋１０Ｐ＋５Ｎｂ＋２Ｔｉ＜２．００・・・（１）式
上記式で元素記号は当該元素の含有量（質量％）を意味する。
［３］さらに質量％で、Ｎｉ：１％以下、Ｃｕ：１％以下、Ｍｏ：１％以下、Ｓｂ：０．２％以下、Ｖ：０．５％以下、Ｗ：０．５％以下、Ｚｒ：０．５％以下、Ｃｏ：０．５％以下、Ｍｇ：０．００５％以下、Ｃａ：０．００５％以下、Ｇａ：０．０２０％以下、Ｌａ：０．１％以下、Ｙ：０．１％以下、Ｈｆ：０．１％以下、ＲＥＭ：０．１％以下の１種または２種以上を含有することを特徴とする本発明のＣｒ系ステンレス鋼板。
［４］高圧水素ガス用機器の金属材料として用いられることを特徴とする本発明のＣｒ系ステンレス鋼板。In order to solve the above problems, the present invention employs the following configuration.
[1] % by mass, C: 0.020% or less, Si: 1.00% or less, Mn: 1.00% or less, P: 0.040% or less, S: 0.0030% or less, Cr: 10 .0 to 18.0%, N: 0.020% or less, Al: 0.10% or less, Nb: 0.5% or less, Ti: 0.5% or less, containing one or two of Sn : 0-0.3%, B: 0-0.005%, Ni: 0-1%, Cu: 0-1%, Mo: 0-1%, Sb: 0.2% or less, V: 0- 0.5%, W: 0-0.5%, Zr: 0-0.5%, Co: 0-0.5%, Mg: 0-0.005%, Ca: 0-0.005%, Ga: 0-0.020%, La: 0-0.1%, Y: 0-0.1%, Hf: 0-0.1%, REM: 0-0.1%, the balance being Fe and impurities A Cr-based stainless steel sheet, wherein the texture on the sheet surface satisfies the following (i) and (ii).
(i) The area ratio of crystal grains in which the angle difference between the normal direction of the steel sheet surface and the {211} plane orientation on the plate surface is within 10° (hereinafter referred to as “{211} ± 10° oriented grains”) is 30. % (ii) In the {211} ± 10° oriented grains defined in (i), both the length in the rolling direction and the length in the width direction are both less than 0.15 mm on average [2] Sn: 0.001 to 0.3%, B: 0.005% or less,
A Cr-based stainless steel sheet according to the present invention, which satisfies the following formula (1).
Si+0.5Mn+10P+5Nb+2Ti<2.00 Formula (1) In the above formula, the element symbol means the content (% by mass) of the element.
[3] Furthermore, in mass%, Ni: 1% or less, Cu: 1% or less, Mo: 1% or less, Sb: 0.2% or less, V: 0.5% or less, W: 0.5% or less, Zr: 0.5% or less, Co: 0.5% or less, Mg: 0.005% or less, Ca: 0.005% or less, Ga: 0.020% or less, La: 0.1% or less, Y: The Cr-based stainless steel sheet of the present invention, containing one or more of 0.1% or less, Hf: 0.1% or less, and REM: 0.1% or less.
[4] The Cr-based stainless steel sheet of the present invention, which is used as a metal material for equipment for high-pressure hydrogen gas.
本発明によれば、耐水素脆性に優れるとともに、低温靭性にも優れたＣｒ系ステンレス鋼板を提供できる。また、本発明のＣｒ系ステンレス鋼板は、高圧水素ガス用機器の金属材料として好適に用いることができる。 ADVANTAGE OF THE INVENTION According to this invention, while being excellent in hydrogen embrittlement resistance, a Cr-type stainless steel plate excellent also in low temperature toughness can be provided. Moreover, the Cr-based stainless steel sheet of the present invention can be suitably used as a metal material for high-pressure hydrogen gas equipment.
本発明者らは、前記した課題を解決するために、Ｃｒ系ステンレス鋼板において、耐水素脆性及び耐低温脆性に及ぼす合金元素と集合組織の影響について鋭意検討を行い，下記の新しい知見を得て本発明をなすに至った。 In order to solve the above-mentioned problems, the inventors of the present invention conducted intensive studies on the effects of alloying elements and textures on hydrogen embrittlement resistance and low-temperature embrittlement resistance in Cr-based stainless steel sheets, and obtained the following new findings. The inventors have completed the present invention.
（ａ）上述のように、高圧水素ガス用機器の金属材料に求められる特性には、耐水素脆性及び耐低温脆性がある。Ｃｒ系ステンレス鋼板は、オーステナイト系ステンレス鋼板に比べて高圧水素ガス中から鋼材へ侵入する水素量が結晶構造に由来して低減するものの、高圧水素ガス用途に好適な耐水素脆性を有するものは得られていない。非特許文献２によれば、水素脆化は塑性変形の関与する機械的性質（強度、伸び、絞り）の低下として特徴づけられる。従って、水素脆化は、高圧水素ガス中から鋼材へ侵入した水素と塑性変形との相互作用により材料の破壊が進行する事象である。近年の研究成果から、水素脆化のメカニズムは水素と塑性変形との相互作用により鋼中において空孔性格子欠陥の生成を助長して破壊が進行する、水素助長歪誘起空孔理論が有力視されている［非特許文献２］。従って、高圧水素ガス用として好適なＣｒ系ステンレス鋼板を実現するためには、水素と塑性変形との相互作用を可能な限り低減させる必要がある。特にＣｒは水素のトラップ能力が大きいために、本発明ではＣｒ量については１８％以下に抑制する。さらに本発明者らは、Ｓｉ、Ｍｎ、Ｐ、Ｔｉ、Ｎｂの添加量を所定の範囲に制御することが好ましいことを知見した。
（ｂ）さらに本発明者らは、高圧水素ガス中で低歪速度引張試験をした場合、水素と塑性変形との相互作用による割れの発生に対して結晶方位の影響があることを突きとめた。水素脆化が顕在化する場合、割れは結晶粒内から発生・進展する頻度が高くなる。結晶粒内の割れは、再結晶集合組織である｛１１１｝方位粒（｛１１１｝面方位が鋼板表面の法線方向を向いた結晶粒）でなく、圧延集合組織である｛２１１｝方位粒（｛２１１｝面方位が鋼板表面の法線方向を向いた結晶粒）で発生する場合が多いことが分かった。これらの事実より、｛２１１｝方位粒は水素と塑性変形との相互作用により歪が導入・蓄積しやすいものと推定される。そして、｛２１１｝方位粒において、前記した空孔性格子欠陥の生成が活発化することで、割れの発生サイトとして作用したものと推察している。このようなメカニズムで進行する水素脆化を抑制するためには、前記した合金元素の範囲を調整することに加えて、｛２１１｝方位粒の面積率とサイズを低下させることが効果的であり、そのしきい値を見出すに至った。
（ｃ）また、高圧水素ガス中から鋼材へ侵入した水素は、結晶粒界を主要な拡散経路として移動する。粒界偏析元素であるＳｎ及びＢの微量添加は、水素の結晶粒界における拡散障壁となって水素と塑性変形との相互作用を低減させる。従来のＣｒ系ステンレス鋼では、結晶粒界にＰやＳの不純物元素が偏析して低温脆性を助長しやすい。そこで本発明者らはＳｎとＢの微量添加に着目し、これら元素を所定の範囲で含有させることにより、ＰやＳ等の悪影響を抑制して耐水素脆性と耐低温脆性の両立が見込まれることを見出した。(a) As described above, properties required for metal materials for high-pressure hydrogen gas equipment include resistance to hydrogen embrittlement and resistance to low temperature embrittlement. Compared to austenitic stainless steel sheets, Cr-based stainless steel sheets have a lower amount of hydrogen penetrating from high-pressure hydrogen gas due to their crystal structure. Not done. According to Non-Patent Document 2, hydrogen embrittlement is characterized as a decrease in mechanical properties (strength, elongation, reduction of area) associated with plastic deformation. Therefore, hydrogen embrittlement is a phenomenon in which material fracture progresses due to the interaction between hydrogen that has penetrated into steel materials from high-pressure hydrogen gas and plastic deformation. Recent research results suggest that the mechanism of hydrogen embrittlement is hydrogen-assisted strain-induced vacancy theory. [Non-Patent Document 2]. Therefore, in order to realize a Cr-based stainless steel sheet suitable for high-pressure hydrogen gas, it is necessary to reduce the interaction between hydrogen and plastic deformation as much as possible. In particular, since Cr has a large ability to trap hydrogen, the amount of Cr is controlled to 18% or less in the present invention. Furthermore, the inventors have found that it is preferable to control the amounts of Si, Mn, P, Ti, and Nb added within a predetermined range.
(b) Furthermore, the present inventors have found that when a low strain rate tensile test is performed in high-pressure hydrogen gas, the crystal orientation has an effect on the occurrence of cracks due to the interaction between hydrogen and plastic deformation. . When hydrogen embrittlement becomes apparent, cracks are more likely to occur and propagate from within grains. The cracks in the grains are not the {111} oriented grains (the {111} plane orientation is in the normal direction of the steel sheet surface), which is the recrystallization texture, but the {211} oriented grains, which are the rolling texture. It was found that the crystal grains in which the {211} plane orientation is oriented in the direction normal to the surface of the steel sheet are often generated. From these facts, it is presumed that {211} oriented grains are likely to introduce and accumulate strain due to interaction between hydrogen and plastic deformation. It is speculated that the activation of the formation of the above-described vacancy lattice defects in the {211} oriented grains acted as crack generation sites. In order to suppress hydrogen embrittlement that progresses by such a mechanism, it is effective to reduce the area ratio and size of {211} oriented grains in addition to adjusting the range of the alloying elements described above. , came to find the threshold.
(c) In addition, hydrogen that has penetrated into the steel material from the high-pressure hydrogen gas moves along grain boundaries as the main diffusion path. The addition of a small amount of Sn and B, which are grain boundary segregation elements, serves as a diffusion barrier for hydrogen at the grain boundaries and reduces the interaction between hydrogen and plastic deformation. In conventional Cr-based stainless steels, impurity elements such as P and S segregate at grain boundaries, which tends to promote low-temperature embrittlement. Therefore, the present inventors focused on the addition of trace amounts of Sn and B, and by containing these elements in a predetermined range, the adverse effects of P, S, etc. are suppressed, and both hydrogen embrittlement resistance and low temperature embrittlement resistance are expected to be compatible. I found out.
上記（ａ）～（ｃ）の知見に基づいて成された本発明の要旨は、以下の通りである。
本実施形態のＣｒ系ステンレス鋼板は、質量％で、Ｃ：０．０２０％以下、Ｓｉ：１．００％以下、Ｍｎ：１．００％以下、Ｐ：０．０４０％以下、Ｓ：０．００３０％以下、Ｃｒ：１０．０～１８．０％、Ｎ：０．０２０％以下、Ａｌ：０．１０％以下、さらにＮｂ：０．５％以下、Ｔｉ：０．５％以下の１種または２種を含み、残部がＦｅおよび不純物からなり、板表面における集合組織が下記（ｉ）および（ii）を満たすことを特徴とする耐水素脆性と耐低温脆性に優れたＣｒ系ステンレス鋼板である。
（ｉ）板表面における鋼板表面の法線方向と｛２１１｝面方位との角度差が１０°以内である結晶粒（｛２１１｝±１０°方位粒）の面積率が３０％未満
（ii）（ｉ）で定義した｛２１１｝±１０°方位粒において、圧延方向の長さおよび板幅方向の長さがいずれも平均で０．１５ｍｍ未満
また、本実施形態のＣｒ系ステンレス鋼板は、さらに質量％で、Ｓｎ：０．００１～０．３％、Ｂ：０．００５％以下を含有し、下記（１）式を満たすことが好ましい。
Ｓｉ＋０．５Ｍｎ＋１０Ｐ＋５Ｎｂ＋２Ｔｉ＜２．００・・・（１）式
上記式で元素記号は当該元素の含有量（質量％）を意味する。
また、本実施形態のＣｒ系ステンレス鋼板は、さらに質量％で、Ｎｉ：１％以下、Ｃｕ：１％以下、Ｍｏ：１％以下、Ｓｂ：０．２％以下、Ｖ：０．５％以下、Ｗ：０．５％以下、Ｚｒ：０．５％以下、Ｃｏ：０．５％以下、Ｍｇ：０．００５％以下、Ｃａ：０．００５％以下、Ｇａ：０．０２０％以下、Ｌａ：０．１％以下、Ｙ：０．１％以下、Ｈｆ：０．１％以下、ＲＥＭ：０．１％以下の１種または２種以上を含有してもよい。
また、本実施形態のＣｒ系ステンレス鋼板は、高圧水素ガス用機器の金属材料として用いられることが好ましい。The gist of the present invention based on the above findings (a) to (c) is as follows.
The Cr-based stainless steel sheet of the present embodiment has C: 0.020% or less, Si: 1.00% or less, Mn: 1.00% or less, P: 0.040% or less, S: 0.040% or less, in terms of % by mass. 0030% or less, Cr: 10.0 to 18.0%, N: 0.020% or less, Al: 0.10% or less, Nb: 0.5% or less, Ti: 0.5% or less or a Cr-based stainless steel sheet having excellent hydrogen embrittlement resistance and low temperature embrittlement resistance, characterized in that it contains two types, the balance being Fe and impurities, and the texture on the sheet surface satisfies the following (i) and (ii): be.
(i) The area ratio of crystal grains ({211} ± 10° oriented grains) in which the angle difference between the normal direction of the steel plate surface and the {211} plane orientation on the plate surface is within 10° is less than 30% (ii) In the {211} ± 10° oriented grains defined in (i), both the length in the rolling direction and the length in the width direction are less than 0.15 mm on average. It is preferable to contain Sn: 0.001 to 0.3% and B: 0.005% or less in mass % and satisfy the following formula (1).
Si+0.5Mn+10P+5Nb+2Ti<2.00 Formula (1) In the above formula, the element symbol means the content (% by mass) of the element.
In addition, the Cr-based stainless steel sheet of the present embodiment further has Ni: 1% or less, Cu: 1% or less, Mo: 1% or less, Sb: 0.2% or less, and V: 0.5% or less in mass %. , W: 0.5% or less, Zr: 0.5% or less, Co: 0.5% or less, Mg: 0.005% or less, Ca: 0.005% or less, Ga: 0.020% or less, La : 0.1% or less, Y: 0.1% or less, Hf: 0.1% or less, and REM: 0.1% or less.
Further, the Cr-based stainless steel sheet of the present embodiment is preferably used as a metal material for high-pressure hydrogen gas equipment.
以下、本発明の各要件について詳しく説明する。なお、各元素の含有量の「％」表示は「質量％」を意味する。 Each requirement of the present invention will be described in detail below. In addition, "%" display of content of each element means "mass%."
Ｃ：０．０２０％以下
Ｃは、固溶および炭化物の析出により鋼の加工硬化を上昇させて耐水素脆性を劣化させ、更には靱性を低下させて耐低温脆性を悪化させるため、その含有量は少ないほどよく、上限を０．０２０％以下とする。ただし、Ｃ量を低減させるには精錬工程が煩雑になりコストが増大する。よってＣ量は０．００１％以上とすることが好ましい。精錬コストも考慮した好ましい範囲は０．００３～０．０１５％であり、更に好ましい範囲は０．００３～０．０１０％である。C: 0.020% or less C increases the work hardening of steel through solid solution and precipitation of carbides, deteriorating hydrogen embrittlement resistance, and further decreases toughness and deteriorating low temperature embrittlement resistance. The lower the better, the upper limit is made 0.020% or less. However, reducing the amount of C complicates the refining process and increases the cost. Therefore, the C content is preferably 0.001% or more. A preferable range considering refining cost is 0.003 to 0.015%, and a more preferable range is 0.003 to 0.010%.
Ｓｉ：１．００％以下
Ｓｉは、脱酸元素として有効である一方、過剰に含有させると固溶強化と加工硬化を上昇させて耐水素脆性ならびに耐低温脆性の低下を招くため、上限を１．００％以下とする。脱酸能力を確保するために下限を０．０１％以上とすることが好ましい。好ましい範囲は、製造性と特性を考慮して０．０５～０．５０％であり、０．０５～０．３０％であってもよい。Si: 1.00% or less Si is effective as a deoxidizing element. .00% or less. The lower limit is preferably 0.01% or more in order to ensure the deoxidizing ability. A preferred range is 0.05 to 0.50%, and may be 0.05 to 0.30%, in consideration of manufacturability and properties.
Ｍｎ：１．００％以下
Ｍｎは、脱酸元素として有効であり、また、Ｓを固定して靭性を改善して耐低温脆性を得るために有効な元素でもある。一方、Ｍｎは過剰に含有させると加工硬化を上昇させて耐水素脆性と耐低温靭性の低下を招くため、上限を１．００％以下とする。脱酸やＳ固定の作用を確保するため、下限は０．０１％以上とすることが好ましい。好ましい範囲は、効果と製造性を考慮して０．０５～０．５０％であり、０．０５～０．３０％であってもよい。Mn: 1.00% or less Mn is effective as a deoxidizing element, and is also an effective element for fixing S to improve toughness and obtain low-temperature embrittlement resistance. On the other hand, if Mn is excessively contained, work hardening is increased and hydrogen embrittlement resistance and low temperature toughness are lowered, so the upper limit is made 1.00% or less. The lower limit is preferably 0.01% or more in order to ensure the deoxidizing and S-fixing effects. A preferable range is 0.05 to 0.50%, and may be 0.05 to 0.30%, in consideration of effect and manufacturability.
Ｐ：０．０４０％以下
Ｐは、粒界偏析して耐低温脆性を低下させる元素であり、その含有量は少ないほどよいため、上限を０．０４０％以下とする。但し、過度の低減は精錬コストの増加に繋がるため、下限を０．００５％以上とすることが好ましい。より好ましい範囲は、製造コストと特性を考慮して０．０１０～０．０３０％であり、０．０１０～０．０２０％であってもよい。P: 0.040% or less P is an element that causes grain boundary segregation to lower the resistance to low-temperature embrittlement. However, excessive reduction leads to an increase in refining costs, so the lower limit is preferably 0.005% or more. A more preferable range is 0.010 to 0.030%, and may be 0.010 to 0.020%, in consideration of manufacturing costs and properties.
Ｓ：０．００３０％以下
Ｓは、粒界偏析や鋼中に硫化物を形成して耐低温脆性を劣化させるため、その含有量は少ないほどよく、上限を０．００３０％以下とする。但し、過度の低減は原料及び精錬コストの増加に繋がるため、下限を０．０００１％以上とすることが好ましい。より好ましい範囲は、製造コストと特性を考慮して０．０００２～０．００１５％であり、０．０００２～０．０００８％であってもよい。S: 0.0030% or less S segregates at grain boundaries and forms sulfides in steel to deteriorate low-temperature embrittlement resistance. However, excessive reduction leads to an increase in raw material and refining costs, so the lower limit is preferably 0.0001% or more. A more preferable range is 0.0002 to 0.0015%, and may be 0.0002 to 0.0008%, in consideration of manufacturing cost and properties.
Ｃｒ：１０．０～１８．０％
Ｃｒは、本実施形態のＣｒ系ステンレス鋼の基本元素であり、鋼の耐食性に加えて耐水素脆性および耐低温脆性を保持するために必須の元素である。本実施形態の高圧水素ガス用途を想定した前記特性を得るために下限を１０．０％以上とする。上限は、耐水素脆性と耐低温脆性を両立する観点から１８．０％以下とする。水素のトラップ能力が高いＣｒが１８．０％を超えると高圧水素ガス環境から鋼中に侵入する水素量が増加して耐水素脆性が劣化するとともに、集合組織が本発明好適範囲から外れることがある。より好ましいＣｒの範囲は、１１．０～１７．０％未満としてもよく、１２．０～１５．０％でもよい。Cr: 10.0-18.0%
Cr is a basic element of the Cr-based stainless steel of this embodiment, and is an essential element for maintaining corrosion resistance, hydrogen embrittlement resistance, and low temperature embrittlement resistance of the steel. The lower limit is made 10.0% or more in order to obtain the above-mentioned characteristics assuming the high-pressure hydrogen gas application of the present embodiment. The upper limit is set to 18.0% or less from the viewpoint of achieving both hydrogen embrittlement resistance and low temperature embrittlement resistance. If Cr, which has a high hydrogen trapping ability, exceeds 18.0%, the amount of hydrogen that penetrates into the steel from the high-pressure hydrogen gas environment increases, deteriorating hydrogen embrittlement resistance, and the texture may deviate from the preferred range of the present invention. be. A more preferable Cr range may be from 11.0 to less than 17.0%, or from 12.0 to 15.0%.
Ｎ：０．０２０％以下
Ｎは、Ｃと同様に、固溶および炭化物の析出により鋼の加工硬化を上昇させて耐水素脆性を劣化させ、更には靱性を低下させて耐低温脆性を悪化させるため、その含有量は少ないほどよく上限を０．０２０％以下とする。ただし、Ｎ量を低減させるには精錬工程が煩雑になりコストが増大する。よってＮ量は０．００１％以上とすることが好ましい。好ましい範囲は、特性と製造コストを考慮して０．００５～０．０１５％である。N: 0.020% or less N, like C, increases work hardening of steel through solid solution and precipitation of carbides, deteriorating hydrogen embrittlement resistance, and further decreases toughness to degrade low temperature embrittlement resistance. Therefore, the lower the content, the better, and the upper limit is made 0.020% or less. However, reducing the amount of N complicates the refining process and increases the cost. Therefore, the N content is preferably 0.001% or more. A preferred range is 0.005 to 0.015% in consideration of properties and manufacturing costs.
Ａｌ：０．１０％以下
Ａｌは、脱酸元素として極めて有効な元素である。一方、鋼の靭性を低下させて耐低温脆性を劣化させるとともに、集合組織が本発明好適範囲から外れることがあるため、上限を０．１０％以下とする。下限は、脱酸効果を考慮して０．００５％以上とすることが好ましい。好ましい範囲は、特性と製造性を考慮して０．０１～０．０７％であり、０．０１～０．０５％であってもよい。Al: 0.10% or less Al is an extremely effective element as a deoxidizing element. On the other hand, the upper limit is made 0.10% or less because it lowers the toughness of the steel and degrades the low-temperature embrittlement resistance, and the texture may deviate from the preferred range of the present invention. The lower limit is preferably 0.005% or more in consideration of the deoxidizing effect. A preferred range is 0.01 to 0.07%, and may be 0.01 to 0.05%, in consideration of properties and manufacturability.
Ｎｂ：０．５％以下、Ｔｉ：０．５％以下の１種または２種
Ｎｂ、Ｔｉは、粒界に偏析することでＰやＳの粒界偏析を抑制して耐低温脆性の改善を図る作用がある。また、Ｎｂ、Ｔｉには、Ｃ，Ｎ，Ｐ，Ｓを固定する安定化元素としての作用により鋼の加工硬化を抑制して耐水素脆性の改善も見込める。Ｎｂ，Ｔｉとも、これら２つの作用を発揮するため、本発明の目標とする耐水素脆性と耐低温脆性の改善に有効な元素となる。含有する場合は、それぞれその効果が発現する０．０１％以上とすることが好ましい。但し、過度な含有は加工硬化を高めて耐水素脆性の低下や合金コストの上昇に繋がり、さらに、靱性が低下して耐低温脆性が劣化するとともに、集合組織が本発明好適範囲から外れることがあるため、上限をそれぞれ０．５％以下とする。好ましい範囲は、前記特性の向上効果と合金コストを考慮して、Ｎｂ、Ｔｉの１種または２種の合計について０．０５～０．５％とする。より好ましい範囲は１種または２種の合計について０．０８～０．４％であり、０．１～０．３％であってもよい。One or two of Nb: 0.5% or less and Ti: 0.5% or less Nb and Ti segregate at grain boundaries to suppress grain boundary segregation of P and S, thereby improving low-temperature embrittlement resistance. There is an action to plan. In addition, Nb and Ti are expected to improve hydrogen embrittlement resistance by suppressing work hardening of steel by acting as stabilizing elements that fix C, N, P, and S. Since both Nb and Ti exhibit these two effects, they are effective elements for improving hydrogen embrittlement resistance and low temperature embrittlement resistance, which are the targets of the present invention. When it is contained, it is preferably 0.01% or more at which the respective effects are exhibited. However, an excessive content increases work hardening, leading to a decrease in hydrogen embrittlement resistance and an increase in alloy cost, and furthermore, toughness decreases, low temperature embrittlement resistance deteriorates, and the texture may deviate from the preferred range of the present invention. Therefore, the upper limit is set to 0.5% or less for each. A preferable range is 0.05 to 0.5% for the sum of one or both of Nb and Ti in consideration of the effect of improving the properties and alloy cost. A more preferred range is 0.08-0.4% for the sum of one or two, and may be 0.1-0.3%.
さらに好ましくは、ＳｎとＢを下記含有量範囲で含有する。
Ｓｎ：０．００１～０．３％
Ｓｎは、本発明の目標とする耐水素脆性と耐低温脆性を向上させるために有効な元素である。粒界偏析元素であるＳｎは、水素の結晶粒界における拡散障壁となって水素と塑性変形との相互作用を低減させる。また、結晶粒界においてＰやＳの偏析を抑制して耐低温脆性の悪影響も緩和する。Ｓｎを所定の範囲で含有させることにより、耐水素脆性と耐低温脆性の両立が見込まれるので、本発明では０．００１～０．５％の範囲で含有させることが好ましい。Ｓｎを０．００１％以上含有させることで、前記の効果が発現されて耐水素脆性が向上する。但し、過度な含有は、結晶粒界におけるＳｎ濃度を増大させて耐低温脆性や製造性の低下を招くため、上限を０．５％以下とする。好ましくは０．００５～０．３％であり、０．０１０～０．２％でもよい。More preferably, Sn and B are contained within the following content ranges.
Sn: 0.001-0.3%
Sn is an effective element for improving hydrogen embrittlement resistance and low temperature embrittlement resistance, which are the targets of the present invention. Sn, which is a grain boundary segregation element, serves as a diffusion barrier for hydrogen at the grain boundaries and reduces the interaction between hydrogen and plastic deformation. In addition, the segregation of P and S at grain boundaries is suppressed, and the adverse effect of low-temperature embrittlement resistance is alleviated. By containing Sn within a predetermined range, both hydrogen embrittlement resistance and low temperature embrittlement resistance can be expected to be achieved. By containing 0.001% or more of Sn, the above effect is exhibited and hydrogen embrittlement resistance is improved. However, an excessive content increases the Sn concentration at the grain boundaries and causes deterioration of low-temperature embrittlement resistance and manufacturability, so the upper limit is made 0.5% or less. It is preferably 0.005 to 0.3%, and may be 0.010 to 0.2%.
Ｂ：０．００５％以下
Ｂは、粒界偏析元素であり、Ｓｎと同様に耐水素脆性と耐低温脆性を向上させる元素であり、本実施形態のＣｒ系ステンレス鋼に含有させることは有効である。本発明では、耐水素脆化特性の向上を図るため０．０００３％以上とすることが好ましい。しかし、過度のＢの含有は、伸びや製造性の低下を招くため、上限を０．００５％以下とする。好ましくは０．０００５～０．００２％とし、０．００１～０．００２％でもよい。B: 0.005% or less B is a grain boundary segregation element, and like Sn, it is an element that improves hydrogen embrittlement resistance and low temperature embrittlement resistance. be. In the present invention, the content is preferably 0.0003% or more in order to improve hydrogen embrittlement resistance. However, excessive B content causes deterioration of elongation and manufacturability, so the upper limit is made 0.005% or less. It is preferably 0.0005 to 0.002%, and may be 0.001 to 0.002%.
Ｓｉ、Ｍｎ、Ｐ、Ｎｂ、Ｔｉは、それぞれ前記した含有量の範囲とするとともに、本発明の目標とする耐水素脆性と耐低温脆性を向上させるために、さらに以下の式（１）を満たすことが好ましい。
Ｓｉ＋０．５Ｍｎ＋１０Ｐ＋５Ｎｂ＋２Ｔｉ＜２．００・・・式（１）
上記式で元素記号は当該元素の含有量（質量％）を意味する。
本発明の目標とする前記特性を向上させるために、式（１）は２．００未満とし、下限は特性と製造性の観点から０．０５とすることが好ましい。好ましい範囲は０．３５～１．８０、より好ましい範囲は０．５０～１．５０である。Si, Mn, P, Nb, and Ti are each in the above-described content range, and in order to improve the hydrogen embrittlement resistance and low temperature embrittlement resistance targeted by the present invention, further satisfy the following formula (1) is preferred.
Si+0.5Mn+10P+5Nb+2Ti<2.00 Expression (1)
In the above formula, the element symbol means the content (% by mass) of the element.
In order to improve the characteristics targeted by the present invention, the formula (1) is preferably less than 2.00, and the lower limit is preferably 0.05 from the viewpoint of characteristics and manufacturability. A preferred range is 0.35 to 1.80, and a more preferred range is 0.50 to 1.50.
上記した元素以外は、Ｆｅおよび不純物からなる。但し、本発明の技術特徴が奏する効果を阻害しない範囲で、上記以外の以下に記載する元素を、選択的に含有させることができる。以下に限定理由を記載する。これらの元素の下限は０％である。 The elements other than those mentioned above consist of Fe and impurities. However, the elements described below other than the above can be selectively contained within a range that does not impair the effects of the technical features of the present invention. The reasons for the limitations are described below. The lower limit of these elements is 0%.
Ｎｉ：１％以下
Ｃｕ：１％以下
Ｍｏ：１％以下
Ｎｉ、Ｃｕ、Ｍｏは耐食性ならびにＮｉとＣｕは耐低温靭性の改善にも有効な元素である。この効果を発揮させるため、Ｎｉ、Ｃｕ、Ｍｏはそれぞれ、０．０５％以上の範囲で含有させてもよい。過度の含有は、ステンレス鋼の固溶強化と加工硬化を上昇させて耐水素脆性の低下を招くため、それぞれ上限は１％以下とする。より好ましい範囲はそれぞれ、０．１％以上０．８％以下であり、更に好ましくは０．２％以上０．５％以下である。Ni: 1% or less Cu: 1% or less Mo: 1% or less Ni, Cu, and Mo are elements effective in improving corrosion resistance, and Ni and Cu are effective in improving low-temperature toughness. In order to exhibit this effect, each of Ni, Cu, and Mo may be contained in a range of 0.05% or more. Excessive content increases solid solution strengthening and work hardening of stainless steel, resulting in a decrease in resistance to hydrogen embrittlement. A more preferable range is 0.1% or more and 0.8% or less, and more preferably 0.2% or more and 0.5% or less.
Ｓｂ：０．２％以下
Ｖ：０．５％以下
Ｗ：０．５％以下
Ｚｒ：０．５％以下
Ｃｏ：０．５％以下
Ｓｂ、Ｖ、Ｗ、Ｚｒ、Ｃｏは、耐食性の改善とＰ、Ｓの粒界偏析を抑制して耐低温脆性の向上に有効な元素であり、必要に応じて含有させる。特にＳｂは強力な粒界偏析元素であり、ＳｎやＢと同様に、Ｐ、Ｓなど不純物元素の粒界偏析を排除する作用を持つ。これらの元素を含有させる場合は、それぞれその効果が発現する０．０１％以上とすることが好ましい。過度な含有は製造性や耐低温脆性の低下に繋がるため、Ｓｂを０．２％以下、Ｖ、Ｗ、Ｚｒ、Ｃｏをそれぞれ０．５％以下とする。より好ましいＳｂの範囲は、０．０２～０．１５％、更に好ましくは０．０２～０．１％以下である。Ｖ、Ｗ、Ｚｒ、Ｃｏのより好ましい範囲は０．０２～０．３％、更に好ましい範囲は０．０２～０．２％である。Sb: 0.2% or less V: 0.5% or less W: 0.5% or less Zr: 0.5% or less Co: 0.5% or less Sb, V, W, Zr and Co improve corrosion resistance. Ni is an element effective in suppressing grain boundary segregation of P and S to improve low-temperature embrittlement resistance, and is contained as necessary. In particular, Sb is a strong grain boundary segregation element and, like Sn and B, has the effect of eliminating grain boundary segregation of impurity elements such as P and S. When these elements are contained, it is preferable to make them 0.01% or more at which the respective effects are exhibited. Since an excessive content leads to a decrease in manufacturability and low-temperature embrittlement resistance, Sb is set to 0.2% or less, and V, W, Zr, and Co are set to 0.5% or less, respectively. A more preferable range of Sb is 0.02 to 0.15%, more preferably 0.02 to 0.1% or less. A more preferable range of V, W, Zr and Co is 0.02 to 0.3%, and a more preferable range is 0.02 to 0.2%.
Ｍｇ：０．００５％以下
Ｍｇは、溶鋼中でＡｌとともにＭｇ酸化物を形成し脱酸剤として作用する他、ＴｉＮの晶出核として作用する。ＴｉＮは凝固過程においてフェライト相の凝固核となり、ＴｉＮの晶出を促進させることで、凝固時にフェライト相を微細生成させることができる。凝固組織を微細化させることにより、耐低温脆性を向上させることもできる。含有させる場合は、これら効果を発現する０．０００１％以上とすることが好ましい。但し、Ｍｇが０．００５％を超えると製造性や耐食性が劣化するため、上限を０．００５％以下とする。好ましくは０．０００３～０．００２％とし、更に好ましくは０．０００３～０．００１％する。Mg: 0.005% or less Mg forms Mg oxide together with Al in molten steel, acts as a deoxidizing agent, and also acts as crystallization nuclei for TiN. TiN serves as solidification nuclei of the ferrite phase in the solidification process, and promotes the crystallization of TiN, so that fine ferrite phases can be generated during solidification. Refining the solidified structure can also improve resistance to low temperature embrittlement. When it is contained, it is preferably 0.0001% or more to exhibit these effects. However, if Mg exceeds 0.005%, manufacturability and corrosion resistance deteriorate, so the upper limit is made 0.005% or less. It is preferably 0.0003 to 0.002%, more preferably 0.0003 to 0.001%.
Ｃａ：０．００５％以下
Ｇａ：０．０２０％以下
Ｃａ、Ｇａは、鋼の清浄度を向上させる元素であり、加工硬化の上昇を抑制して耐水素脆性を高めるため必要に応じて含有させる。含有させる場合は、これら効果を発現するためにそれぞれ０．０００３％以上とすることが好ましい。しかし、過度の含有は製造性や耐食性の劣化に繋がるため、上限をＣａは０．００５％以下、Ｇａは０．０２０％以下とする。好ましくは、Ｃａが０．０００３～０．００３０％とし、Ｇａは０．００３０～０．０１５％する。Ca: 0.005% or less Ga: 0.020% or less Ca and Ga are elements that improve the cleanliness of steel, and are contained as necessary to suppress an increase in work hardening and increase hydrogen embrittlement resistance. . When they are contained, it is preferable to make them 0.0003% or more in order to exhibit these effects. However, since an excessive content leads to deterioration of manufacturability and corrosion resistance, the upper limit of Ca is set to 0.005% or less and the upper limit of Ga is set to 0.020% or less. Preferably, Ca is 0.0003-0.0030% and Ga is 0.0030-0.015%.
Ｌａ：０．１％以下
Ｙ：０．１％以下
Ｈｆ：０．１％以下
ＲＥＭ：０．１％以下
Ｌａ、Ｙ、Ｈｆ、ＲＥＭは、Ｃａ、Ｇａと同様に鋼の清浄度を向上させる元素であり、加工硬化の上昇を抑制して耐水素脆性を高めるため必要に応じて含有してもよい。含有させる場合は、効果が発現するためにそれぞれ０．００１％以上とすることが好ましい。しかし、過度の含有は、合金コストの上昇と製造性の劣化に繋がるため、上限をそれぞれ０．１％以下とする。好ましくはそれぞれ０．００１～０．０５％とし、更に好ましくは０．００１～０．０３％とする。La: 0.1% or less Y: 0.1% or less Hf: 0.1% or less REM: 0.1% or less La, Y, Hf, and REM improve the cleanliness of steel like Ca and Ga. It is an element, and may be contained as necessary in order to suppress an increase in work hardening and improve hydrogen embrittlement resistance. When they are contained, it is preferable to make them 0.001% or more in order to obtain the effect. However, an excessive content leads to an increase in alloy cost and deterioration in manufacturability, so the upper limit is made 0.1% or less. Preferably, each is 0.001 to 0.05%, more preferably 0.001 to 0.03%.
ＲＥＭ（希土類元素）は、スカンジウム（Ｓｃ）、イットリウム（Ｙ）の２元素と、周期律表においてセリウム（Ｃｅ）からルテチウム（Ｌｕ）までの１４元素（ランタノイド）の総称を指す。これらの元素は単独で含有させてもよいし、混合物であってもよい。 REM (rare earth element) is a general term for two elements, scandium (Sc) and yttrium (Y), and 14 elements (lanthanoids) from cerium (Ce) to lutetium (Lu) in the periodic table. These elements may be contained singly or as a mixture.
なお、残部に含まれる不純物とは、鋼を工業的に製造する際に、原料としての鉱石、スクラップ、または製造環境などから混入されるものであって、本発明の課題を解決する限度において許容されるものを意味する。必要に応じてＴａ：０．１％以下、Ｂｉ：０．０１％以下、Ｚｎ：０．０５％、Ｈ：０．０００５％以下を含有してもよい。本実施形態のＣｒ系ステンレス鋼は、フェライトの結晶粒を含有するもので、マルテンサイトの結晶粒を含有するものであってもよい。 The impurities contained in the balance are those mixed from ore, scrap, or the manufacturing environment as raw materials when steel is manufactured industrially, and are allowed to the extent that the problems of the present invention can be solved. means to be If necessary, Ta: 0.1% or less, Bi: 0.01% or less, Zn: 0.05%, and H: 0.0005% or less may be contained. The Cr-based stainless steel of the present embodiment contains ferrite crystal grains, and may contain martensite crystal grains.
次に本実施形態のＣｒ系ステンレス鋼板の集合組織について説明する。本実施形態のＣｒ系ステンレス鋼板は、板表面における集合組織が下記の（ｉ）および（ii）を満たすものである。
（ｉ）板表面における鋼板表面の法線方向と｛２１１｝面方位との角度差が１０°以内である結晶粒（｛２１１｝±１０°方位粒）の面積率が３０％未満
（ii）（ｉ）で定義した｛２１１｝±１０°方位粒において、圧延方向の長さおよび板幅方向の長さがいずれも平均で０．１５ｍｍ未満
ここで｛２１１｝面方位とは、｛２１１｝面の法線方向を意味する。Next, the texture of the Cr-based stainless steel sheet of this embodiment will be described. The Cr-based stainless steel sheet of this embodiment has a texture on the sheet surface that satisfies the following (i) and (ii).
(i) The area ratio of crystal grains ({211} ± 10° oriented grains) in which the angle difference between the normal direction of the steel plate surface and the {211} plane orientation on the plate surface is within 10° is less than 30% (ii) In the {211} ± 10 ° oriented grains defined in (i), both the length in the rolling direction and the length in the sheet width direction are less than 0.15 mm on average. means the normal direction of the face.
｛２１１｝方位はα－ｆｉｂｅｒと呼ばれ、冷間圧延で集積する圧延集合組織である。本発明ではこれら耐水素脆性を向上させるために、板表面において割れの発生サイトとなる頻度が高い｛２１１｝±１０°方位粒の面積率とサイズを制御することが効果的であることを知見した。｛２１１｝±１０°方位粒の面積率は３０％未満とし、板表面において再結晶集合組織である｛１１１｝方位の存在比率を高めることで耐水素脆性の向上に寄与することができる。耐水素脆性と製造性の観点から、｛２１１｝±１０°方位粒の面積率の好ましい範囲は５～２０％、より好ましい範囲は３～１５％である。 The {211} orientation is called α-fiber, and is a rolling texture that accumulates during cold rolling. In the present invention, in order to improve these hydrogen embrittlement resistance, it is effective to control the area ratio and size of {211} ± 10 ° oriented grains that frequently become cracking sites on the plate surface. did. The area ratio of {211}±10° oriented grains is set to less than 30%, and by increasing the existence ratio of {111} orientation, which is the recrystallized texture, on the plate surface, it is possible to contribute to the improvement of hydrogen embrittlement resistance. From the viewpoint of hydrogen embrittlement resistance and manufacturability, the area ratio of {211}±10° oriented grains is preferably in the range of 5 to 20%, more preferably in the range of 3 to 15%.
また、板表面において｛２１１｝±１０°方位粒のサイズは圧延方向および板幅方向（圧延垂直方向）の長さはいずれも平均で０．１５ｍｍ未満とする。｛２１１｝±１０°方位粒のサイズを細分化することで｛２１１｝±１０°方位粒への歪の導入・蓄積が緩和されて、耐水素脆性の向上に寄与する。耐水素脆性と製造性の観点から、｛２１１｝±１０°方位粒の好ましいサイズは０．１０ｍｍ未満であり、より好ましくは０．０７ｍｍ未満である。 In addition, the size of {211}±10° oriented grains on the surface of the sheet shall be less than 0.15 mm on average in both the rolling direction and the sheet width direction (perpendicular to rolling). By subdividing the size of the {211}±10° oriented grains, the introduction and accumulation of strain in the {211}±10° oriented grains is alleviated, contributing to the improvement of hydrogen embrittlement resistance. From the viewpoint of hydrogen embrittlement resistance and manufacturability, the preferred size of {211}±10° oriented grains is less than 0.10 mm, more preferably less than 0.07 mm.
本発明において、「板表面」とは、鋼板の板厚ｔのｔ／８までの領域であり、鋼板の表面から当該鋼板の両側の面方向に１／８ｔの厚さまでの領域をいう。また、｛２１１｝±１０°方位粒とは、上記板表面において、鋼板表面の法線方向と｛２１１｝面方位との角度差が１０°以内である結晶方位を持つ結晶粒をいう。 In the present invention, the term "plate surface" refers to a region up to t/8 of the plate thickness t of the steel plate, and refers to a region from the surface of the steel plate to a thickness of 1/8t in both lateral directions of the steel plate. Also, {211}±10° oriented grains refer to crystal grains having a crystal orientation in which the angular difference between the normal direction of the steel sheet surface and the {211} plane orientation is within 10° on the plate surface.
前記した集合組織については、電子線後方散乱回折法（以下、ＥＢＳＤ）を用いて解析することができる。ＥＢＳＤは、試料表面のミクロ領域における結晶粒毎の結晶方位を高速に測定・解析するものである。耐水素脆性に寄与する結晶方位集団は、板表面における｛２１１｝±１０°方位粒とその他の領域に分割した結晶方位マップを表示させて、｛２１１｝±１０°方位粒の面積率や粒子サイズを数値化することができる。例えば、鋼板表面から鋼板の板厚ｔのｔ／８までの、鋼板表面に平行な面において、板幅方向８５０μｍ、圧延方向２２５０μｍの測定領域で倍率１００としてＥＢＳＤの測定を行い、鋼板表面に平行な面の法線方向と｛２１１｝面方位との角度差が１０°以内である結晶粒（すなわち｛２１１｝±１０°方位粒）の結晶方位マップを表示させてその面積率ならびに粒子径のサイズ（圧延方向、板幅方向）を数値化することができる。鋼板表面から鋼板の板厚ｔのｔ／８までの範囲を検査面とすれば、板表面の集合組織を再現性よく評価することができる。 The texture described above can be analyzed using an electron beam backscatter diffraction method (hereinafter referred to as EBSD). EBSD measures and analyzes the crystal orientation of each crystal grain in the micro region of the sample surface at high speed. The crystal orientation group that contributes to hydrogen embrittlement resistance is obtained by displaying a crystal orientation map divided into {211} ± 10 ° orientation grains and other regions on the plate surface, and determining the area ratio of {211} ± 10 ° orientation grains and grains. Size can be quantified. For example, in a plane parallel to the steel sheet surface from the steel sheet surface to t / 8 of the thickness t of the steel sheet, EBSD is measured at a magnification of 100 in a measurement area of 850 μm in the width direction and 2250 μm in the rolling direction, parallel to the steel plate surface. Display the crystal orientation map of the crystal grains (i.e. {211} ± 10 ° oriented grains) in which the angle difference between the normal direction of the plane and the {211} plane orientation is within 10 °, and the area ratio and grain diameter The size (rolling direction, plate width direction) can be quantified. If the range from the surface of the steel sheet to t/8 of the thickness t of the steel sheet is used as the inspection surface, the texture of the surface of the steel sheet can be evaluated with good reproducibility.
耐水素脆性は、歪速度の比較的小さい低歪速度引張試験で評価するものとし、歪速度は１０－５／ｓとすることが好ましい。歪速度の比較的大きい１０－４／ｓ以上の場合、鋼中への水素の侵入と拡散が進行せずに鋼の水素脆性が軽減する場合もある。一方、歪速度の小さい１０－６／ｓの場合、過度な試験時間を要するとともに水素脆化特性への影響も飽和する。耐水素脆性は、前記した低歪速度引張試験において引張強さや破断伸びで評価し、大気中もしくは不活性ガス中の引張強さや破断伸びと比較して高圧水素ガス中での値が低下し難いほど良好である。ここで、高圧水素ガス中の引張強さを大気中もしくは不活性ガス中の引張強さで除した値を「相対引張強さ」と呼ぶ。高圧水素ガス中の破断伸びを大気中もしくは不活性ガス中の破断伸びで除した値を「相対伸び」と呼ぶ。本実施形態のＣｒ系ステンレス鋼板は、相対引張強さは０．９８以上、相対伸びは０．７５以上であることが好ましい。より好ましい範囲は、相対引張強さが０．９８～１．０５、相対伸びが０．８５～１．０５である。Hydrogen embrittlement resistance is evaluated by a low strain rate tensile test with a relatively low strain rate, preferably at a strain rate of 10 −5 /s. When the strain rate is 10 −4 /s or more, which is relatively high, the penetration and diffusion of hydrogen into the steel may not progress, and the hydrogen embrittlement of the steel may be reduced. On the other hand, a low strain rate of 10 −6 /s requires an excessive test time and saturates the effect on the hydrogen embrittlement characteristics. Hydrogen embrittlement resistance is evaluated by tensile strength and elongation at break in the low strain rate tensile test described above, and the value in high-pressure hydrogen gas is less likely to decrease than the tensile strength and elongation at break in the atmosphere or in an inert gas. the better. Here, the value obtained by dividing the tensile strength in high-pressure hydrogen gas by the tensile strength in air or inert gas is called "relative tensile strength". The value obtained by dividing the elongation at break in high-pressure hydrogen gas by the elongation at break in air or inert gas is called "relative elongation". The Cr-based stainless steel sheet of the present embodiment preferably has a relative tensile strength of 0.98 or more and a relative elongation of 0.75 or more. A more preferred range is a relative tensile strength of 0.98 to 1.05 and a relative elongation of 0.85 to 1.05.
耐低温脆性は、ＪＩＳ Ｚ ２２４２に準拠するシャルピー衝撃試験で評価するものとし、例えばＶノッチの２ｍｍ厚試験片を使用して吸収エネルギーを測定する。耐低温脆性は、前記ＪＩＳの附属書Ｄに準拠したエネルギー遷移温度で評価し、エネルルギー遷移温度が低いほど良好である。エネルギー遷移温度とは、延性破壊による破面率１００％となる温度における吸収エネルギーの１／２の値に相当する温度である。本実施形態のＣｒ系ステンレス鋼板は、屋外や車載用の水素機器での使用を考慮してエネルギー遷移温度が－１０℃以下であることが好ましい。より好ましくは寒冷地域での使用に配慮して－４０℃以下である。 Low-temperature embrittlement resistance is evaluated by a Charpy impact test conforming to JIS Z 2242, for example, by measuring absorbed energy using a V-notch 2 mm thick test piece. The low-temperature embrittlement resistance is evaluated by the energy transition temperature in accordance with Annex D of JIS, and the lower the energy transition temperature, the better. The energy transition temperature is the temperature corresponding to half the absorbed energy at the temperature at which the ductile fracture rate becomes 100%. The Cr-based stainless steel sheet of the present embodiment preferably has an energy transition temperature of −10° C. or lower in consideration of its use in outdoor or vehicle-mounted hydrogen equipment. More preferably, it is -40°C or less in consideration of use in cold regions.
次に、本実施形態のＣｒ系ステンレス鋼板の製造方法について説明する。
本実施形態のＣｒ系ステンレス鋼板は上記の化学成分を満足すれば、鋳造、熱間圧延、冷間圧延等の通常のプロセス条件で製造しても本発明の目標とする耐水素脆性と耐低温脆性を確保できる場合もある。
本実施形態のＣｒ系ステンレス鋼板は、本発明の集合組織を形成して耐水素脆性を向上させるために、上記の化学成分を満足するとともに、以下の製造方法が好ましい。Next, a method for manufacturing a Cr-based stainless steel sheet according to this embodiment will be described.
If the Cr-based stainless steel sheet of the present embodiment satisfies the above chemical composition, it can be manufactured under normal process conditions such as casting, hot rolling, cold rolling, etc., and has the hydrogen embrittlement resistance and low temperature resistance targeted by the present invention. In some cases, brittleness can be ensured.
In order to form the texture of the present invention and improve hydrogen embrittlement resistance, the Cr-based stainless steel sheet of the present embodiment preferably satisfies the chemical components described above and is manufactured by the following method.
前記した化学組成を有する鋼を熱間圧延後、９００℃以下で熱延後焼鈍し、その後に圧下率４０％以上の冷間圧延を行い、９００℃超の温度で仕上げ焼鈍を行うことが好ましい。熱間圧延後の熱処理（熱延後焼鈍）は、熱間圧延段階で生成した｛２１１｝方位粒の成長を抑制するために９００℃以下、より好ましい範囲は７００～９００℃である。 It is preferable that the steel having the chemical composition described above is hot rolled, then annealed after hot rolling at 900°C or less, then cold rolled at a rolling reduction of 40% or more, and finish annealed at a temperature above 900°C. . The heat treatment after hot rolling (annealing after hot rolling) is carried out at 900° C. or less, more preferably 700 to 900° C., in order to suppress the growth of {211} oriented grains generated in the hot rolling stage.
冷間圧延は、可逆式の２０段ゼンジミア圧延機や６段あるいは１２段圧延機で実施しても良く、複数パスを連続的に圧延するタンデム圧延機で実施しても良い。本発明の集合組織を形成するには、ワークロール径は大きい方が好ましい。そのため、ワークロール径は２００ｍｍ以上とすることが好ましい。このような大径ロール圧延は、１次冷延（複数回冷延を繰返し行う場合の初期冷延）時に実施すると好ましい。これにより再結晶集合組織である｛１１１｝方位粒が発達し、圧延集合組織である｛２１１｝±１０°方位粒の面積率が低減するので、本発明の目標とする集合組織の形成に有効である。冷間圧延は、４０％以上の圧下率で実施することが好ましい。冷間圧延率が４０％未満の場合、再結晶集合組織において｛２１１｝±１０°方位粒の面積率とサイズが上昇しやすくなり、耐水素脆性の低下を招く場合がある。耐水素脆性と製造性の観点から、好ましい圧下率の範囲は４０～９０％であり、より好ましい範囲は５０～８０％である。 The cold rolling may be performed by a reversible 20-high Sendzimir rolling mill, a 6-high or 12-high rolling mill, or a tandem rolling mill that continuously performs multiple passes. In order to form the texture of the present invention, it is preferable that the work roll diameter is large. Therefore, it is preferable that the diameter of the work roll is 200 mm or more. Such large-diameter roll rolling is preferably carried out during primary cold rolling (initial cold rolling when cold rolling is repeated multiple times). As a result, {111} orientation grains, which are recrystallized textures, are developed, and the area ratio of {211} ± 10° orientation grains, which are rolling textures, is reduced. is. Cold rolling is preferably carried out at a rolling reduction of 40% or more. If the cold rolling rate is less than 40%, the area ratio and size of {211}±10° oriented grains in the recrystallized texture tend to increase, which may lead to deterioration of hydrogen embrittlement resistance. From the viewpoint of resistance to hydrogen embrittlement and manufacturability, the rolling reduction is preferably in the range of 40 to 90%, more preferably in the range of 50 to 80%.
冷間圧延後の仕上げ焼鈍は、｛１１１｝方位粒を発達させて｛２１１｝方位粒の面積率とサイズを低減させるために、９００℃超で熱処理することが好ましい。過度な温度上昇は、結晶粒成長により｛２１１｝±１０°方位粒のサイズを上昇させるため、仕上げ焼鈍温度の上限は１０５０℃であることが好ましい。また、仕上げ焼鈍時の雰囲気は特に規定するものではないが、大気中、ＬＮＧ燃料雰囲気、ＢＡ雰囲気であることが好ましい。 The final annealing after cold rolling is preferably a heat treatment above 900° C. in order to develop {111} oriented grains and reduce the area ratio and size of {211} oriented grains. An excessive temperature rise increases the size of {211}±10° oriented grains due to grain growth, so the upper limit of the final annealing temperature is preferably 1050°C. Also, the atmosphere during the final annealing is not particularly specified, but it is preferably in air, in an LNG fuel atmosphere, or in a BA atmosphere.
熱処理（仕上げ焼鈍）の均熱時間は、１０秒～１０分とすることが好ましい。均熱時間が１０秒以上であれば、冷間圧延のための材料の軟質化が図れるので好ましい。また、均熱時間が１０分以下であれば、｛２１１｝±１０°方位粒の成長を抑制して当該結晶粒のサイズを小さく抑え、耐水素脆性に有効な集合組織を確保することができる。 The soaking time for the heat treatment (finish annealing) is preferably 10 seconds to 10 minutes. A soaking time of 10 seconds or more is preferable because the material can be softened for cold rolling. In addition, if the soaking time is 10 minutes or less, the growth of {211} ± 10 ° oriented grains can be suppressed, the size of the grains can be suppressed, and a texture effective for hydrogen embrittlement resistance can be secured. .
以下、本発明の実施例を説明する。 Examples of the present invention will be described below.
表１の成分組成を有するＣｒ系ステンレス鋼を溶製した。表１のＮｂ、Ｔｉ、Ｓｎ、Ｂの含有量において、「０．０」と記載したものは当該元素を添加していないことを意味する。 A Cr-based stainless steel having the chemical composition shown in Table 1 was melted. Regarding the contents of Nb, Ti, Sn, and B in Table 1, "0.0" means that the element was not added.
加熱温度１１５０～１２５０℃まで加熱して熱間圧延を行い、板厚５．０ｍｍの熱延鋼板を製造した。熱延鋼板を７００～９００℃の範囲にて熱延後焼鈍し、酸洗後に板厚１．５～２．５ｍｍの範囲で冷間圧延して冷延鋼板とした。冷延条件は表２に示す。冷間圧延は異なるワークロール径のゼンジミア圧延機とタンデム圧延機で実施し、前者は小径ロール（６０ｍｍ）（表２で「Ｓ」と表示）、後者は大径ロール（２００ｍｍ）（表２で「Ｌ」と表示）を使用した。冷延鋼板に対して９２０～１０２０℃の仕上げ焼鈍と酸洗を行い、Ｃｒ系ステンレス鋼板を製造した。 A hot-rolled steel sheet having a thickness of 5.0 mm was produced by heating to a heating temperature of 1150 to 1250° C. and performing hot rolling. A hot-rolled steel sheet was hot-rolled at 700 to 900° C., annealed, pickled, and then cold-rolled to a thickness of 1.5 to 2.5 mm to obtain a cold-rolled steel sheet. Cold rolling conditions are shown in Table 2. Cold rolling was performed on a Sendzimir mill and a tandem mill with different work roll diameters, the former using a small diameter roll (60 mm) (labeled “S” in Table 2) and the latter using a large diameter roll (200 mm) (labeled “S” in Table 2). "L") was used. A cold-rolled steel sheet was subjected to finish annealing at 920 to 1020° C. and pickling to produce a Cr-based stainless steel sheet.
集合組織は、ＥＢＳＤを用いて解析した。耐水素脆性に寄与する結晶方位集団は、板表面における｛２１１｝±１０°方位粒とその他の領域に分割した結晶方位マップを表示させて数値化した。すなわち、鋼板表面から鋼板の板厚ｔのｔ／８範囲の、鋼板表面に平行な面において、板幅方向８５０μｍ、圧延方向２２５０μｍの測定領域で倍率１００としてＥＢＳＤの測定を行い、鋼板表面に平行な面の法線方向と｛２１１｝面方位との角度差が１０°以内である結晶粒（すなわち｛２１１｝±１０°方位粒）の結晶方位マップを表示し、併せて結晶粒界を表示し、当該結晶粒の面積率と平均粒子径（圧延方向および板幅方向）を測定した。表２の｛２１１｝±１０°方位粒の「サイズ」欄の表記は、「圧延方向／板幅方向」を意味する。また、一部の比較例については、参考として板厚中心（ｔ／２）における測定結果も併記した。結晶方位が１５°以上異なる部位を結晶粒界とした。 Texture was analyzed using EBSD. The crystal orientation group contributing to hydrogen embrittlement resistance was quantified by displaying a crystal orientation map divided into {211}±10° oriented grains and other regions on the plate surface. That is, in a plane parallel to the steel sheet surface in the range of t / 8 of the thickness t of the steel sheet from the steel sheet surface, EBSD is measured at a magnification of 100 in a measurement area of 850 μm in the width direction and 2250 μm in the rolling direction. Display the crystal orientation map of the crystal grain in which the angle difference between the normal direction of the plane and the {211} plane orientation is within 10 ° (that is, the {211} ± 10 ° orientation grain), and also display the grain boundary Then, the area ratio and average particle size (rolling direction and plate width direction) of the crystal grains were measured. The notation in the "size" column of {211}±10° oriented grains in Table 2 means "rolling direction/sheet width direction". For some comparative examples, the measurement results at the thickness center (t/2) are also shown for reference. A portion where the crystal orientation differs by 15° or more was defined as a grain boundary.
得られたＣｒ系ステンレス鋼板は、水素脆性および低温脆性の評価に供した。耐水素脆性は比較材として市販の２ｍｍ厚ＳＵＳ３１６Ｌ鋼板（１７．５％Ｃｒ－１２％Ｎｉ－２％Ｍｏ）およびＳＵＳ３１６鋼板（１７．５％Ｃｒ－１０％Ｎｉ－２％Ｍｏ）を評価に用いた。 The obtained Cr-based stainless steel sheets were subjected to evaluation of hydrogen embrittlement and low temperature embrittlement. Hydrogen embrittlement resistance was evaluated using commercially available 2mm thick SUS316L steel plate (17.5%Cr-12%Ni-2%Mo) and SUS316 steel plate (17.5%Cr-10%Ni-2%Mo) as comparative materials. board.
水素脆性の評価は、以下の手順で実施した。
平行部の幅４ｍｍ、長さ２０ｍｍの引張試験片を作製し、高圧水素ガス中での引張試験直前に表面を乾式＃６００エメリー紙で研磨後に有機溶剤で脱脂洗浄した。高圧水素ガス中の引張試験は、表１に示すように水素ガスの圧力を２０ＭＰａ又は４５ＭＰａとし、試験温度は－４０℃、歪速度は１０－５／ｓで行った。比較の引張試験は、－４０℃の０．１ＭＰａ窒素中で実施した。高圧水素ガス中の引張強さを０．１ＭＰａ窒素中の引張強さで除して相対引張強さとし、高圧水素ガス中の破断伸びを０．１ＭＰａ窒素中の破断伸びで除して相対伸びとした。耐水素脆性は、相対引張強さと相対伸びを評価指標として評価した。評価基準は以下の通りとした。ＡおよびＢを合格とした。
Ａ：相対引張強さ０．９８以上かつ相対伸び０．８５以上を満たす。
Ｂ：上記以外で相対引張強さ０．９８以上かつ相対伸び０．７５以上を満たす。
Ｘ：相対引張強さ０．９８未満または相対伸び０．７５未満の何れか一方または両方である。
ここで、水素ガスの圧力４５ＭＰａ、試験温度－４０℃の場合、ＳＵＳ３１６Ｌ鋼板は相対伸び０．７５未満となり評価はＸとなる。また、水素ガスの圧力２０ＭＰａ、試験温度－４０℃の場合、ＳＵＳ３１６鋼板は相対伸び０．７５未満となり評価はＸとなる。Evaluation of hydrogen embrittlement was performed in the following procedure.
A tensile test piece having a parallel portion width of 4 mm and a length of 20 mm was prepared, and the surface was polished with dry #600 emery paper and then degreased and washed with an organic solvent immediately before the tensile test in high-pressure hydrogen gas. The tensile test in high-pressure hydrogen gas was performed at a hydrogen gas pressure of 20 MPa or 45 MPa, a test temperature of −40° C., and a strain rate of 10 −5 /s, as shown in Table 1. Comparative tensile tests were performed in 0.1 MPa nitrogen at -40°C. The tensile strength in high-pressure hydrogen gas is divided by the tensile strength in 0.1 MPa nitrogen to obtain relative tensile strength, and the breaking elongation in high-pressure hydrogen gas is divided by the breaking elongation in 0.1 MPa nitrogen to obtain relative elongation. did. Hydrogen embrittlement resistance was evaluated using relative tensile strength and relative elongation as evaluation indices. The evaluation criteria were as follows. A and B were regarded as passing.
A: Satisfies relative tensile strength of 0.98 or more and relative elongation of 0.85 or more.
B: Other than the above, a relative tensile strength of 0.98 or more and a relative elongation of 0.75 or more are satisfied.
X: Either or both of a relative tensile strength of less than 0.98 or a relative elongation of less than 0.75.
Here, when the hydrogen gas pressure is 45 MPa and the test temperature is −40° C., the relative elongation of the SUS316L steel plate is less than 0.75 and the evaluation is X. When the hydrogen gas pressure is 20 MPa and the test temperature is −40° C., the relative elongation of the SUS316 steel plate is less than 0.75 and the evaluation is X.
低温脆性の評価は、ＪＩＳ Ｚ ２２４２に準拠したシャルピー衝撃試験で行った。試験片は１．５～２．５ｍｍ厚×１０ｍｍ幅×５５ｍｍ長さのＶノッチ形状とし、試験温度は－１００℃から室温（２０℃）の範囲とした。耐低温脆性は、シャルピー試験で測定した吸収エネルギーから前記したエネルギー遷移温度を求めて評価指標とした。評価基準は以下の通りとした。ＡおよびＢを合格とした。
Ａ：エネルギー遷移温度－４０℃以下を満たす。
Ｂ：エネルギー遷移温度－４０℃超－１０℃以下を満たす。
Ｘ：エネルギー遷移温度－１０℃超である。Low temperature embrittlement was evaluated by a Charpy impact test conforming to JIS Z 2242. The test piece had a V-notch shape with a thickness of 1.5 to 2.5 mm, a width of 10 mm, and a length of 55 mm. The low-temperature embrittlement resistance was obtained as an evaluation index by obtaining the energy transition temperature described above from the absorbed energy measured by the Charpy test. The evaluation criteria were as follows. A and B were regarded as passing.
A: Satisfies the energy transition temperature of −40° C. or lower.
B: Satisfies the energy transition temperature of more than -40°C and -10°C or less.
X: The energy transition temperature is higher than -10°C.
表２に試験結果をまとめて示す。
Ｎｏ．１～１１は、何れも本発明範囲の化学成分と集合組織を有するＣｒ系ステンレス鋼板であり、耐水素脆性及び耐低温脆性が良好であった。特に、好ましい成分と集合組織の範囲としたＮｏ．５、６、９、１０は、水素ガスの圧力４５ＭＰａにおいて耐水素脆性指標が「Ｂ」または「Ａ」であり、その耐水素脆性はＳＵＳ３１６Ｌと比較しても高位であった。また、Ｎｏ．６、８、１０は大径ロールを使用して｛２１１｝±１０°方位粒を低減したものであり、同じ化学成分でありながらＮｏ．５、７、９に比べて耐水素脆性が更に向上した。Table 2 summarizes the test results.
No. All of Nos. 1 to 11 are Cr-based stainless steel sheets having chemical compositions and textures within the range of the present invention, and exhibit good hydrogen embrittlement resistance and low temperature embrittlement resistance. In particular, No. 6, which is a range of preferred components and textures. 5, 6, 9, and 10 had a hydrogen embrittlement resistance index of "B" or "A" at a hydrogen gas pressure of 45 MPa, and their hydrogen embrittlement resistance was higher than that of SUS316L. Also, No. Nos. 6, 8 and 10 use large-diameter rolls to reduce {211}±10° oriented grains. Hydrogen embrittlement resistance was further improved compared to 5, 7 and 9.
Ｎｏ．１２～２０は、何れも本発明範囲の化学成分を有しないＣｒ系ステンレス鋼板であり、本発明範囲の集合組織を形成できず、耐水素脆性または耐低温脆性のいずれか一方または両方が劣位となった。また、Ｎｏ．１７、１９、２０は、板厚中心の｛２１１｝±１０°方位粒の面積率は３０％未満であるが板表面における当該面積率は３０％を超えており、耐水素脆性と耐低温脆性を共に得るためには、板表面における面積率を制御することが重要であると分かる。 No. Nos. 12 to 20 are all Cr-based stainless steel sheets that do not have the chemical composition within the range of the present invention, cannot form the texture within the range of the present invention, and are inferior in either or both hydrogen embrittlement resistance and low temperature embrittlement resistance. became. Also, No. 17, 19, and 20, the area ratio of {211} ± 10 ° oriented grains at the center of the plate thickness is less than 30%, but the area ratio on the plate surface exceeds 30%, and hydrogen embrittlement resistance and low temperature embrittlement resistance It can be seen that it is important to control the area ratio on the plate surface in order to obtain both
以上の評価結果から、本発明範囲の成分と集合組織を有することでＣｒ系ステンレス鋼板の耐水素脆性は市中のＳＵＳ３１６と比べて高位であった。さらに、好ましい成分を有して大径ロールを使用して好ましい集合組織に制御することで、ＳＵＳ３１６Ｌを凌ぐ耐水素脆性となることが分かった。 From the above evaluation results, the hydrogen embrittlement resistance of the Cr-based stainless steel sheet was higher than that of commercially available SUS316 by having the composition and texture within the range of the present invention. Furthermore, it was found that the hydrogen embrittlement resistance surpassing that of SUS316L can be obtained by controlling the texture to be preferable by using a large-diameter roll having preferable components.
Claims (4)
Ｃ：０．０２０％以下、
Ｓｉ：１．００％以下、
Ｍｎ：１．００％以下、
Ｐ：０．０４０％以下、
Ｓ：０．００３０％以下、
Ｃｒ：１０．０～１８．０％、
Ｎ：０．０２０％以下、
Ａｌ：０．１０％以下、
さらに、Ｎｂ：０．５％以下、Ｔｉ：０．５％以下の１種または２種を含み、
Ｓｎ：０～０．３％、
Ｂ：０～０．００５％、
Ｎｉ：０～１％、
Ｃｕ：０～１％、
Ｍｏ：０～１％、
Ｓｂ：０．２％以下、
Ｖ：０～０．５％、
Ｗ：０～０．５％、
Ｚｒ：０～０．５％、
Ｃｏ：０～０．５％、
Ｍｇ：０～０．００５％、
Ｃａ：０～０．００５％、
Ｇａ：０～０．０２０％、
Ｌａ：０～０．１％、
Ｙ：０～０．１％、
Ｈｆ：０～０．１％、
ＲＥＭ：０～０．１％、
残部がＦｅおよび不純物からなり、板表面における集合組織が下記の（ｉ）および（ii）を満たすことを特徴とするＣｒ系ステンレス鋼板。
（ｉ）板表面における鋼板表面の法線方向と｛２１１｝面方位との角度差が１０°以内である結晶粒（以下「｛２１１｝±１０°方位粒」という。）の面積率が３０％未満
（ii）（ｉ）で定義した｛２１１｝±１０°方位粒において、圧延方向の長さおよび板幅方向の長さがいずれも平均で０．１５ｍｍ未満in % by mass,
C: 0.020% or less,
Si: 1.00% or less,
Mn: 1.00% or less,
P: 0.040% or less,
S: 0.0030% or less,
Cr: 10.0 to 18.0%,
N: 0.020% or less,
Al: 0.10% or less,
Furthermore, Nb: 0.5% or less, Ti: 0.5% or less, containing one or two types,
Sn: 0-0.3%,
B: 0 to 0.005%,
Ni: 0-1%,
Cu: 0-1%,
Mo: 0-1%,
Sb: 0.2% or less,
V: 0 to 0.5%,
W: 0 to 0.5%,
Zr: 0 to 0.5%,
Co: 0-0.5%,
Mg: 0-0.005%,
Ca: 0-0.005%,
Ga: 0 to 0.020%,
La: 0 to 0.1%,
Y: 0 to 0.1%,
Hf: 0-0.1%,
REM: 0-0.1%,
A Cr-based stainless steel sheet, the balance being composed of Fe and impurities, and having a texture on the sheet surface that satisfies the following (i) and (ii).
(i) The area ratio of crystal grains in which the angle difference between the normal direction of the steel sheet surface and the {211} plane orientation on the plate surface is within 10° (hereinafter referred to as “{211} ± 10° oriented grains”) is 30. % (ii) In {211} ± 10° oriented grains defined in (i), both the length in the rolling direction and the length in the width direction are less than 0.15 mm on average
下記（１）式を満たすことを特徴とする請求項１に記載のＣｒ系ステンレス鋼板。
Ｓｉ＋０．５Ｍｎ＋１０Ｐ＋５Ｎｂ＋２Ｔｉ＜２．００・・・（１）式
上記式で元素記号は当該元素の含有量（質量％）を意味する。Furthermore, in mass%, Sn: 0.001 to 0.3%, B: 0.005% or less,
The Cr-based stainless steel sheet according to claim 1, wherein the following formula (1) is satisfied.
Si+0.5Mn+10P+5Nb+2Ti<2.00 Formula (1) In the above formula, the element symbol means the content (% by mass) of the element.
Ｎｉ：１％以下、
Ｃｕ：１％以下、
Ｍｏ：１％以下、
Ｓｂ：０．２％以下、
Ｖ：０．５％以下、
Ｗ：０．５％以下、
Ｚｒ：０．５％以下、
Ｃｏ：０．５％以下、
Ｍｇ：０．００５％以下、
Ｃａ：０．００５％以下、
Ｇａ：０．０２０％以下、
Ｌａ：０．１％以下、
Ｙ：０．１％以下、
Ｈｆ：０．１％以下、
ＲＥＭ：０．１％以下
の１種または２種以上を含有することを特徴とする請求項１または請求項２に記載のＣｒ系ステンレス鋼板。Furthermore, in mass %,
Ni: 1% or less,
Cu: 1% or less,
Mo: 1% or less,
Sb: 0.2% or less,
V: 0.5% or less,
W: 0.5% or less,
Zr: 0.5% or less,
Co: 0.5% or less,
Mg: 0.005% or less,
Ca: 0.005% or less,
Ga: 0.020% or less,
La: 0.1% or less,
Y: 0.1% or less,
Hf: 0.1% or less,
3. The Cr-based stainless steel sheet according to claim 1, containing one or more of REM: 0.1% or less.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009013478A (en) | 2007-07-05 | 2009-01-22 | Nippon Steel Corp | High-rigidity and high-strength cold-rolled steel sheet and manufacturing method therefor |
| WO2012043877A1 (en) | 2010-09-29 | 2012-04-05 | 新日鐵住金ステンレス株式会社 | Austenite high-manganese stainless steel, manufacturing method therefor, and member using said steel |
| JP2012107333A (en) | 2010-10-28 | 2012-06-07 | Jfe Steel Corp | High-strength steel for high-pressure hydrogen storage container |
| WO2013133259A1 (en) | 2012-03-09 | 2013-09-12 | 新日鐵住金ステンレス株式会社 | Ferrite-austenite 2-phase stainless steel plate having low in-plane anisotropy and method for producing same |
| WO2015159554A1 (en) | 2014-04-17 | 2015-10-22 | 新日鐵住金株式会社 | Austenitic stainless steel and method for producing same |
| WO2018008658A1 (en) | 2016-07-04 | 2018-01-11 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel, steel sheet thereof, and methods for producing these |
| JP2018119196A (en) | 2017-01-27 | 2018-08-02 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel plate for heat-resistant member fastening parts having excellent heat resistance, and fastening part, and circular clamp for heat-resistant tubular members |
Family Cites Families (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04371550A (en) * | 1991-06-18 | 1992-12-24 | Nisshin Steel Co Ltd | Alloy member for sealing |
| EP1225242B1 (en) * | 2001-01-18 | 2004-04-07 | JFE Steel Corporation | Ferritic stainless steel sheet with excellent workability and method for making the same |
| JP3788311B2 (en) * | 2001-10-31 | 2006-06-21 | Ｊｆｅスチール株式会社 | Ferritic stainless steel sheet and manufacturing method thereof |
| JP3886864B2 (en) * | 2002-08-26 | 2007-02-28 | 日新製鋼株式会社 | Ferritic stainless steel cold-rolled annealed material excellent in secondary workability and manufacturing method thereof |
| JP4167587B2 (en) * | 2003-02-28 | 2008-10-15 | 新日本製鐵株式会社 | High-strength steel sheet excellent in hydrogen embrittlement resistance and method for producing the same |
| JP4700263B2 (en) | 2003-04-25 | 2011-06-15 | 新日本製鐵株式会社 | High-pressure hydrogen gas tank and piping |
| JP3886933B2 (en) * | 2003-06-04 | 2007-02-28 | 日新製鋼株式会社 | Ferritic stainless steel sheet excellent in press formability and secondary workability and manufacturing method thereof |
| JP5196807B2 (en) * | 2007-02-26 | 2013-05-15 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel sheet excellent in formability with low roughness of processing surface and method for producing the same |
| JP5610796B2 (en) * | 2010-03-08 | 2014-10-22 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel with excellent corrosion resistance in condensed water environment generated from hydrocarbon combustion exhaust gas |
| JP5793459B2 (en) * | 2012-03-30 | 2015-10-14 | 新日鐵住金ステンレス株式会社 | Heat-resistant ferritic stainless steel cold-rolled steel sheet excellent in workability, ferritic stainless hot-rolled steel sheet for cold-rolled material, and production method thereof |
| JP6089657B2 (en) | 2012-12-07 | 2017-03-08 | 愛知製鋼株式会社 | Austenitic stainless steel for high pressure hydrogen having excellent sensitivity to hydrogen embrittlement at low temperature and method for producing the same |
| JP5843982B2 (en) * | 2013-02-04 | 2016-01-13 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel sheet with excellent workability and method for producing the same |
| JPWO2015098981A1 (en) | 2013-12-27 | 2017-03-23 | 国立大学法人九州大学 | Base material for hydrogen equipment and method for producing the same |
| JP5908936B2 (en) * | 2014-03-26 | 2016-04-26 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel sheet for flange, manufacturing method thereof and flange part |
| MX2017005210A (en) * | 2014-10-31 | 2017-07-26 | Nippon Steel & Sumikin Sst | Ferrite-based stainless steel plate, steel pipe, and production method therefor. |
| JP6684620B2 (en) | 2015-03-26 | 2020-04-22 | 日鉄ステンレス株式会社 | High-strength austenitic stainless steel excellent in hydrogen embrittlement resistance, its manufacturing method, and hydrogen equipment used in high-pressure hydrogen gas and liquid hydrogen environment |
-
2019
- 2019-12-18 EP EP19899311.5A patent/EP3901292A4/en active Pending
- 2019-12-18 WO PCT/JP2019/049717 patent/WO2020130060A1/en unknown
- 2019-12-18 KR KR1020217018922A patent/KR102539588B1/en active IP Right Grant
- 2019-12-18 JP JP2020561497A patent/JP7121142B2/en active Active
- 2019-12-18 US US17/312,693 patent/US20220033944A1/en active Pending
- 2019-12-18 CN CN201980083521.9A patent/CN113227414B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009013478A (en) | 2007-07-05 | 2009-01-22 | Nippon Steel Corp | High-rigidity and high-strength cold-rolled steel sheet and manufacturing method therefor |
| WO2012043877A1 (en) | 2010-09-29 | 2012-04-05 | 新日鐵住金ステンレス株式会社 | Austenite high-manganese stainless steel, manufacturing method therefor, and member using said steel |
| JP2012107333A (en) | 2010-10-28 | 2012-06-07 | Jfe Steel Corp | High-strength steel for high-pressure hydrogen storage container |
| WO2013133259A1 (en) | 2012-03-09 | 2013-09-12 | 新日鐵住金ステンレス株式会社 | Ferrite-austenite 2-phase stainless steel plate having low in-plane anisotropy and method for producing same |
| WO2015159554A1 (en) | 2014-04-17 | 2015-10-22 | 新日鐵住金株式会社 | Austenitic stainless steel and method for producing same |
| WO2018008658A1 (en) | 2016-07-04 | 2018-01-11 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel, steel sheet thereof, and methods for producing these |
| JP2018119196A (en) | 2017-01-27 | 2018-08-02 | 新日鐵住金ステンレス株式会社 | Ferritic stainless steel plate for heat-resistant member fastening parts having excellent heat resistance, and fastening part, and circular clamp for heat-resistant tubular members |
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