JP2010174308A - Corrosion-resistant austenitic stainless steel and manufacturing method therefor - Google Patents
Corrosion-resistant austenitic stainless steel and manufacturing method therefor Download PDFInfo
- Publication number
- JP2010174308A JP2010174308A JP2009016887A JP2009016887A JP2010174308A JP 2010174308 A JP2010174308 A JP 2010174308A JP 2009016887 A JP2009016887 A JP 2009016887A JP 2009016887 A JP2009016887 A JP 2009016887A JP 2010174308 A JP2010174308 A JP 2010174308A
- Authority
- JP
- Japan
- Prior art keywords
- corrosion
- stainless steel
- austenitic stainless
- mass
- resistant austenitic
- 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.)
- Pending
Links
Landscapes
- Heat Treatment Of Steel (AREA)
Abstract
Description
本発明は、耐食性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し、特に、原子力発電プラント等の構成材料として好適な耐食性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。 The present invention relates to a corrosion-resistant austenitic stainless steel and a method for producing the same, and particularly to a corrosion-resistant austenitic stainless steel suitable as a constituent material for a nuclear power plant and the like and a method for producing the same.
従来から、オーステナイト系ステンレス鋼は、高温強度、耐食性、加工性等に優れた材料として工業的に広く使用されている。また、このようなオーステナイト系ステンレス鋼は、例えば、原子力発電プラントにおける沸騰水型原子炉の炉心シュラウドの構成材料に使用されている。 Conventionally, austenitic stainless steel has been widely used industrially as a material excellent in high temperature strength, corrosion resistance, workability, and the like. In addition, such austenitic stainless steel is used as a constituent material of a core shroud of a boiling water reactor in a nuclear power plant, for example.
上記のようなオーステナイト系ステンレス鋼では、例えば、溶接線近傍の熱影響部の結晶粒界上にクロム炭化物が生成し、これに伴って生じる結晶粒界に沿ったクロム欠乏相に沿って応力腐食割れ（ＳＣＣ）、特に粒界応力腐食割れ（ＩＧＳＣＣ）が進展する傾向があった。 In the austenitic stainless steel as described above, for example, chromium carbide is formed on the grain boundary of the heat-affected zone near the weld line, and stress corrosion occurs along the chromium-deficient phase along the grain boundary caused by this. There was a tendency for cracks (SCC), especially intergranular stress corrosion cracking (IGSCC) to develop.
上記のようなオーステナイト系ステンレス鋼の耐粒界腐食特性を高めるための方法として、クロムよりも炭素との反応速度及び／又は結合力が大きい元素、例えばチタンやニオブ等を添加して、クロムより先にチタンやニオブ等と炭素を結合させることによって、クロム炭化物析出による粒界クロム濃度の低下を抑制する方法が知られている（例えば、特許文献１参照。）。 As a method for enhancing the intergranular corrosion resistance of the austenitic stainless steel as described above, an element having a higher reaction rate and / or binding force with carbon than chromium, for example, titanium or niobium, is added, so that A method is known in which the decrease in grain boundary chromium concentration due to chromium carbide precipitation is suppressed by previously bonding carbon with titanium, niobium, or the like (see, for example, Patent Document 1).
現在、原子力発電プラント等では、次世代炉の必要条件として長寿命・高稼働率が求められている。このため、原子力発電プラント等を構成するための材料についても、より耐食性の高い材料を提供する必要性が高まっている。 At present, nuclear power plants and the like are required to have a long life and high availability as a necessary condition for the next generation furnace. For this reason, the necessity for providing a material having higher corrosion resistance is increasing as a material for constituting a nuclear power plant or the like.
上記したように、オーステナイト系ステンレス鋼の耐粒界腐食特性を高めるためにチタン等を添加する手法は、通常の環境下で使用される材料についてはその効果が期待されている。 As described above, the technique of adding titanium or the like in order to enhance the intergranular corrosion resistance of austenitic stainless steel is expected to be effective for materials used in a normal environment.
しかしながら、原子力発電プラントのような高温・高圧かつ中性子照射を受ける環境下における使用では、熱や中性子照射の影響を受けて材料の劣化が生じ、炭化チタン（ＴｉＣ）等の析出の偏りや、粒径のばらつきなどによって、期待どおりの特性を得られないという懸念が生じる。 However, when used in an environment such as a nuclear power plant that is exposed to neutron irradiation at a high temperature and high pressure, the material deteriorates due to the effects of heat and neutron irradiation, resulting in uneven precipitation of titanium carbide (TiC), etc. There is a concern that the expected characteristics cannot be obtained due to variations in diameter.
本発明は、上記従来の事情に対処してなされたもので、従来に比べてより耐粒界腐食特性を高めた耐食性オーステナイト系ステンレス鋼およびその製造方法を提供しようとするものである。 The present invention has been made in response to the above-described conventional circumstances, and an object of the present invention is to provide a corrosion-resistant austenitic stainless steel having improved intergranular corrosion resistance as compared with the conventional one and a method for producing the same.
本発明の耐食性オーステナイト系ステンレス鋼の一態様は、クロムを１４〜２５質量％、ニッケルを１０〜２４質量％含み、かつ炭素を含む耐食性オーステナイト系ステンレス鋼であって、添加元素としてのチタンを、チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が１０〜３０の範囲となるように添加して耐粒界腐食特性を向上させたことを特徴とする。 One aspect of the corrosion-resistant austenitic stainless steel of the present invention is a corrosion-resistant austenitic stainless steel containing 14 to 25% by mass of chromium, 10 to 24% by mass of nickel and containing carbon, and titanium as an additive element. It is characterized by adding the mass ratio of titanium content to carbon content (Ti mass / C mass) in a range of 10 to 30 to improve the intergranular corrosion resistance.
本発明の耐食性オーステナイト系ステンレス鋼の製造方法の一態様は、クロムを１４〜２５質量％、ニッケルを１０〜２４質量％含み、かつ炭素を含む耐食性オーステナイト系ステンレス鋼の製造方法であって、添加元素としてのチタンを、チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が１０〜３０の範囲となるように添加することによって耐粒界腐食特性を向上させることを特徴とする。 One aspect of the method for producing a corrosion-resistant austenitic stainless steel according to the present invention is a method for producing a corrosion-resistant austenitic stainless steel containing 14 to 25% by mass of chromium, 10 to 24% by mass of nickel, and carbon. Titanium as an element is added so that the mass ratio of titanium content to carbon content (Ti mass / C mass) is in the range of 10 to 30, thereby improving the intergranular corrosion resistance. .
本発明によれば、従来に比べてより耐粒界腐食特性を高めた耐食性オーステナイト系ステンレス鋼およびその製造方法を提供することができる。 ADVANTAGE OF THE INVENTION According to this invention, the corrosion-resistant austenitic stainless steel which improved the intergranular corrosion characteristic more compared with the past, and its manufacturing method can be provided.
以下、本発明に係る耐食性オーステナイト系ステンレス鋼およびその製造方法を、図面を参照して実施形態について説明する。 Hereinafter, embodiments of a corrosion-resistant austenitic stainless steel and a method for producing the same according to the present invention will be described with reference to the drawings.
本実施形態に係る耐食性オーステナイト系ステンレス鋼は、クロムを１４〜２５質量％、ニッケルを１０〜２４質量％含むとともに、炭素を含む。そして、添加元素としてのチタンが、チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が１０〜３０の範囲となるように添加され、これによって、チタンを添加しない場合に比べて耐食性が向上した耐食性オーステナイト系ステンレス鋼となっている。なお、添加元素としてのチタンの含有量は、０．１質量％以上とすることが好ましい。 The corrosion-resistant austenitic stainless steel according to the present embodiment contains 14 to 25% by mass of chromium, 10 to 24% by mass of nickel, and carbon. Then, titanium as an additive element is added so that the mass ratio of titanium content to carbon content (Ti mass / C mass) is in the range of 10 to 30, thereby comparing with the case where titanium is not added. Corrosion resistant austenitic stainless steel with improved corrosion resistance. Note that the content of titanium as the additive element is preferably 0.1% by mass or more.
このような耐食性オーステナイト系ステンレス鋼の代表的な組成を、表１に示す。なお、表１において、残部は鉄であり、単位は質量％である。 Table 1 shows a typical composition of such a corrosion-resistant austenitic stainless steel. In Table 1, the balance is iron, and the unit is mass%.
表１に示す耐食性オーステナイト系ステンレス鋼は、添加元素としてのチタンを、チタン含有量が０．２９質量％（０．１質量％以上）となるように添加したものである。また、この耐食性オーステナイト系ステンレス鋼は、炭素を０．０２５質量％含んでいる。したがって、チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が約１２であり、１０〜３０の範囲となっている。 The corrosion-resistant austenitic stainless steel shown in Table 1 is obtained by adding titanium as an additive element so that the titanium content is 0.29% by mass (0.1% by mass or more). Further, this corrosion-resistant austenitic stainless steel contains 0.025% by mass of carbon. Therefore, the mass ratio of titanium content to carbon content (Ti mass / C mass) is about 12, which is in the range of 10-30.
表１に示した組成となるように、添加元素としてのチタンを添加して実際に作製した実施例の耐食性オーステナイト系ステンレス鋼の組織を顕微鏡によって拡大した写真を図１に示す。図１の写真に示すように、この耐食性オーステナイト系ステンレス鋼の結晶粒径は、約５０μｍ程度の整粒となっていた。 The photograph which expanded the structure | tissue of the corrosion-resistant austenitic stainless steel of the Example actually produced by adding titanium as an additional element so that it might become the composition shown in Table 1 with a microscope is shown in FIG. As shown in the photograph of FIG. 1, the crystal grain size of the corrosion-resistant austenitic stainless steel was about 50 μm.
上記のように、添加元素としてのチタンを、その含有量が０．２９質量％、チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が約１２となるように添加した表１に示す組成の耐食性オーステナイト系ステンレス鋼を実施例として作製し、この実施例の耐食性オーステナイト系ステンレス鋼について、粒界腐食試験（ヒューイ試験（６５％硝酸腐食試験（ＪＩＳ Ｇ０５７３）））を行った。この粒界腐食試験の結果を、縦軸を腐食速度（ｇ／ｍ２／ｈ）とした図２のグラフに示す。なお、粒界腐食試験は、実施例の耐食性オーステナイト系ステンレス鋼に対して７００℃で１０時間の熱処理を施した後に行った。この場合の腐食速度は、０．１５ｇ／ｍ２／ｈであった。 As described above, titanium as an additive element was added so that the content was 0.29 mass%, and the mass ratio of titanium content to carbon content (Ti mass / C mass) was about 12. A corrosion-resistant austenitic stainless steel having the composition shown in FIG. 5 was prepared as an example, and the corrosion-resistant austenitic stainless steel of this example was subjected to a grain boundary corrosion test (Hughy test (65% nitric acid corrosion test (JIS G0573))). The results of this intergranular corrosion test are shown in the graph of FIG. 2 with the vertical axis representing the corrosion rate (g / m 2 / h). In addition, the intergranular corrosion test was performed after performing the heat processing for 10 hours at 700 degreeC with respect to the corrosion-resistant austenitic stainless steel of an Example. The corrosion rate in this case was 0.15 g / m 2 / h.
また、比較のために、添加元素としてのチタンを添加していない従来のオーステナイト系ステンレス鋼についても、同様な粒界腐食試験を行った。この粒界腐食試験の結果を図２のグラフに示す。この従来のオーステナイト系ステンレス鋼の腐食速度は、２０ｇ／ｍ２／ｈ以上となった。 For comparison, a similar intergranular corrosion test was also performed on a conventional austenitic stainless steel not added with titanium as an additive element. The results of this intergranular corrosion test are shown in the graph of FIG. The corrosion rate of this conventional austenitic stainless steel was 20 g / m 2 / h or more.
図２に示されるように、上記のように添加元素としてのチタンを添加した実施例の耐食性オーステナイト系ステンレス鋼（図２のＴｉ添加オーステナイト鋼）は、チタンを添加していない従来のオーステナイト系ステンレス鋼（図２のオーステナイト鋼）に比べて腐食速度が１／１００以下程度と極めて遅くなっており、高い耐粒界腐食特性を示すことが確認できた。 As shown in FIG. 2, the corrosion-resistant austenitic stainless steel of the example added with titanium as an additive element as described above (Ti-added austenitic steel in FIG. 2) is a conventional austenitic stainless steel not added with titanium. Compared to steel (austenitic steel in FIG. 2), the corrosion rate was extremely slow, about 1/100 or less, and it was confirmed that high intergranular corrosion resistance was exhibited.
すなわち、上記のように、添加元素としてのチタンを、その含有量が０．２９質量％、チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が約１２となるように添加した実施例では、クロム炭化物析出による粒界クロム濃度の低下を抑制する効果が発揮され、高い耐粒界腐食特性を示している。 That is, as described above, titanium as an additive element was added so that the content was 0.29 mass%, and the mass ratio of titanium content to carbon content (Ti mass / C mass) was about 12. In the examples, the effect of suppressing the decrease in intergranular chromium concentration due to chromium carbide precipitation is exhibited, and high intergranular corrosion resistance is exhibited.
添加元素としてのチタンは、上記したとおりクロムより先に炭素と結合することによってクロム炭化物の析出による粒界クロム濃度の低下を抑制する。このため、含有されている炭素の量によってチタンの添加量を調整する必要がある。 Titanium as an additive element suppresses a decrease in intergranular chromium concentration due to precipitation of chromium carbide by bonding to carbon prior to chromium as described above. For this reason, it is necessary to adjust the addition amount of titanium by the amount of contained carbon.
この場合、含有されている炭素の量に対して、チタンの量は、ある程度多くする必要があり、炭素に対するチタンの質量比（Ｔｉ／Ｃ）は、１０以上程度とする必要がある。一方、チタン添加による粒界クロム濃度低下の抑制効果は、チタン添加量を増大させても一定量以上では飽和する傾向となるため、炭素に対するチタンの質量比（Ｔｉ／Ｃ）は、３０以下程度とすることが好ましく、１５以下程度とすることがさらに好ましい。 In this case, the amount of titanium needs to be increased to some extent with respect to the amount of carbon contained, and the mass ratio of titanium to carbon (Ti / C) needs to be about 10 or more. On the other hand, the effect of suppressing the decrease in intergranular chromium concentration due to the addition of titanium tends to saturate at a certain amount or more even if the amount of titanium added is increased, so the mass ratio of titanium to carbon (Ti / C) is about 30 or less Preferably, it is more preferably about 15 or less.
すなわち、炭素に対するチタンの質量比（Ｔｉ／Ｃ）は、１０〜３０とすることが好ましく、１０〜１５とすることがさらに好ましい。また、耐食性オーステナイト系ステンレス鋼全体に対するチタンの含有量は、ある程度多い方が、チタン添加による粒界クロム濃度低下の抑制効果を確実かつ均一にすることができる。このため、チタンの含有量は、０．１質量％以上〜１．０質量％以下程度とすることが好ましく、０．１５質量％以上〜０．６質量％以下程度とすることがさらに好ましい。 That is, the mass ratio of titanium to carbon (Ti / C) is preferably 10-30, and more preferably 10-15. In addition, when the content of titanium in the corrosion-resistant austenitic stainless steel as a whole is large to some extent, the effect of suppressing the decrease in the intergranular chromium concentration due to the addition of titanium can be made sure and uniform. For this reason, it is preferable to make content of titanium into about 0.1 mass% or more and 1.0 mass% or less, and it is further more preferable to set it as about 0.15 mass% or more and 0.6 mass% or less.
なお、上記の実施形態では、添加元素としてチタンを用いた場合について説明したが、チタンの代わりに、クロムよりも先に炭化物を生成することが可能なニオブ又はジルコニウムを添加元素として用いて、オーステナイト系ステンレス鋼の耐粒界腐食特性を向上させることも可能である。 In the above embodiment, the case where titanium is used as an additive element has been described. However, instead of titanium, niobium or zirconium capable of generating a carbide prior to chromium is used as an additive element, and austenite is used. It is also possible to improve the intergranular corrosion resistance of the stainless steel.
次に、上記した実施例の耐食性オーステナイト系ステンレス鋼の結晶の粒径を微細化する微細化工程について図３を参照して説明する。同図に示すように、この微細化工程では、まず、上記した範囲となる量のチタンを含む材料１を圧延機２にかけて冷間圧延する（ａ）。この冷間圧延の際の圧延率は、３０％以上程度とすることが好ましい。 Next, the refinement | miniaturization process which refines | miniaturizes the crystal grain diameter of the corrosion-resistant austenitic stainless steel of an above-described Example is demonstrated with reference to FIG. As shown in the figure, in this miniaturization step, first, the material 1 containing titanium in an amount in the above-described range is cold-rolled on a rolling mill 2 (a). The rolling rate during this cold rolling is preferably about 30% or more.
次に、冷間圧延した材料１を、電気炉３等において所定時間所定温度に加熱する（ｂ）。この加熱の際の加熱温度は、８００℃以上１０００℃以下程度とすることが好ましい。 Next, the cold-rolled material 1 is heated to a predetermined temperature for a predetermined time in an electric furnace 3 or the like (b). The heating temperature in this heating is preferably about 800 ° C. or higher and 1000 ° C. or lower.
しかる後、加熱した材料１を、冷却ファン６等を用いて冷却する（ｃ）。この冷却の際は、熱電対５および温度測定器４で材料１の温度を監視し、所定の冷却速度となるように温度を制御しつつ冷却を行う。この際の冷却速度は、例えば、５００℃以上の温度において１℃／秒以上５０℃／秒以下程度とすることが好ましい。 Thereafter, the heated material 1 is cooled using a cooling fan 6 or the like (c). At the time of cooling, the temperature of the material 1 is monitored by the thermocouple 5 and the temperature measuring device 4, and cooling is performed while controlling the temperature so as to obtain a predetermined cooling rate. The cooling rate at this time is preferably about 1 ° C./second to 50 ° C./second at a temperature of 500 ° C. or higher.
上記の工程で、耐食性オーステナイト系ステンレス鋼の結晶の粒径はある程度微細化される。このように、１回の冷間圧延、加熱、冷却による微細化を行った耐食性オーステナイト系ステンレス鋼の組織を拡大した顕微鏡写真を図４（Ａ）に示す。 In the above process, the crystal grain size of the corrosion-resistant austenitic stainless steel is refined to some extent. FIG. 4 (A) shows an enlarged micrograph of the structure of the corrosion-resistant austenitic stainless steel that has been refined by one cold rolling, heating, and cooling.
耐食性オーステナイト系ステンレス鋼をさらに微細化する場合は、図３に示すように、引き続き、材料１を圧延機２にかけて冷間圧延する（ｄ）。次に、冷間圧延した材料１を、電気炉３等において所定時間所定温度に加熱する（ｅ）。しかる後、加熱した材料１を、冷却ファン６等を用いて冷却する（ｆ）。なお、冷却する際は、熱電対５および温度測定器４で材料１の温度を監視し、所定の冷却速度となるように温度を制御しつつ冷却を行う。 In order to further refine the corrosion-resistant austenitic stainless steel, as shown in FIG. 3, the material 1 is subsequently cold-rolled by using a rolling mill 2 (d). Next, the cold-rolled material 1 is heated to a predetermined temperature for a predetermined time in the electric furnace 3 or the like (e). Thereafter, the heated material 1 is cooled using a cooling fan 6 or the like (f). When cooling, the temperature of the material 1 is monitored by the thermocouple 5 and the temperature measuring device 4, and cooling is performed while controlling the temperature so as to obtain a predetermined cooling rate.
上記の２回目の冷間圧延における圧延率は、３０％以上程度とすることが好ましく、２回目の加熱における加熱温度は８００℃以上１０００℃以下程度とすることが好ましく、２回目の冷却における冷却速度は、５００℃以上の温度において１℃／秒以上５０℃／秒以程度とすることが好ましいことは、上記した１回目の工程の場合と同様である。しかし、１回目の圧延率、加熱温度、冷却速度と、２回目の圧延率、加熱温度、冷却速度が異なっていてもよい。 The rolling rate in the second cold rolling is preferably about 30% or more, and the heating temperature in the second heating is preferably about 800 ° C. or more and 1000 ° C. or less, and cooling in the second cooling is performed. The speed is preferably about 1 ° C./second or more and 50 ° C./second or less at a temperature of 500 ° C. or higher, as in the case of the first step described above. However, the first rolling rate, heating temperature, and cooling rate may be different from the second rolling rate, heating temperature, and cooling rate.
上記のように、２回の冷間圧延、加熱、冷却による微細化を行った耐食性オーステナイト系ステンレス鋼の組織を拡大した顕微鏡写真を図４（Ｂ）に示す。図４（Ｂ）に示されるように、１回のみ上記の冷間圧延、加熱、冷却による微細化を行った耐食性オーステナイト系ステンレス鋼に比べて、２回の冷間圧延、加熱、冷却による微細化を行った耐食性オーステナイト系ステンレス鋼は、結晶粒がより整粒化され微細化されていることが確認できた。 FIG. 4B shows an enlarged micrograph of the structure of the corrosion-resistant austenitic stainless steel that has been refined by cold rolling, heating, and cooling twice as described above. As shown in FIG. 4 (B), compared with the corrosion-resistant austenitic stainless steel that has been refined by cold rolling, heating, and cooling only once, fineness by cold rolling, heating, and cooling twice. It was confirmed that the corrosion-resistant austenitic stainless steel that had been refined was further refined and refined in crystal grains.
上記のように、前述した実施例の耐食性オーステナイト系ステンレス鋼に、２回の冷間圧延、加熱、冷却工程を施し、粒径の微細化を行った耐食性オーステナイト系ステンレス鋼について、前述したと同様な粒界腐食試験（ヒューイ試験（６５％硝酸腐食試験（ＪＩＳ Ｇ０５７３）））を行った。この粒界腐食試験の結果を、縦軸を腐食速度（ｇ／ｍ２／ｈ）とした図５のグラフに示す。 As described above, the corrosion-resistant austenitic stainless steel obtained by subjecting the corrosion-resistant austenitic stainless steel of the above-described examples to two cold rolling, heating, and cooling steps to refine the grain size is the same as described above. The intergranular corrosion test (Huey test (65% nitric acid corrosion test (JIS G0573))) was performed. The results of this intergranular corrosion test are shown in the graph of FIG. 5 with the vertical axis representing the corrosion rate (g / m 2 / h).
図５に示されるように、上記の粒径の微細化を行った耐食性オーステナイト系ステンレス鋼についても、チタンを添加していない従来のオーステナイト系ステンレス鋼（図５のオーステナイト鋼）に比べて腐食速度が１／２００以下程度と極めて遅くなっており、高い耐粒界腐食特性を示すことが確認できた。なお、この場合の腐食速度は、０．０８５ｇ／ｍ２／ｈであった。 As shown in FIG. 5, the corrosion rate of the corrosion-resistant austenitic stainless steel with the above-mentioned refined grain size is also higher than that of the conventional austenitic stainless steel not added with titanium (the austenitic steel of FIG. 5). Is very slow, about 1/200 or less, and high intergranular corrosion resistance was confirmed. In this case, the corrosion rate was 0.085 g / m 2 / h.
図５に示されるように、実施例の耐食性オーステナイト系ステンレス鋼では、粒径の微細化を行わない場合と、粒径の微細化を行った場合のいずれの場合についても、高い耐粒界腐食特性を得られることが確認できた。すなわち、結晶の粒径が、１〜７０μｍ程度の範囲内において、同様な高い耐粒界腐食特性が得られることが分かった。 As shown in FIG. 5, in the corrosion-resistant austenitic stainless steel of the example, high intergranular corrosion resistance is obtained in both cases where the grain size is not refined and when the grain size is refined. It was confirmed that characteristics could be obtained. That is, it was found that the same high intergranular corrosion resistance can be obtained when the crystal grain size is in the range of about 1 to 70 μm.
上述したように、本実施形態によれば、粒界クロム濃度の低下を抑制することができ、従来に比べてより耐粒界腐食特性の高い耐食性オーステナイト系ステンレス鋼およびその製造方法を提供することができる。 As described above, according to the present embodiment, it is possible to suppress a decrease in the intergranular chromium concentration, and to provide a corrosion-resistant austenitic stainless steel having a higher intergranular corrosion resistance than the conventional one and a method for producing the same. Can do.
１…材料、２…圧延機、３…電気炉、４…温度測定器、５…熱電対、６…ファン。 DESCRIPTION OF SYMBOLS 1 ... Material, 2 ... Rolling mill, 3 ... Electric furnace, 4 ... Temperature measuring instrument, 5 ... Thermocouple, 6 ... Fan.
Claims (12)
添加元素としてのチタンを、チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が１０〜３０の範囲となるように添加して耐粒界腐食特性を向上させたことを特徴とする耐食性オーステナイト系ステンレス鋼。 A corrosion-resistant austenitic stainless steel containing 14 to 25% by mass of chromium, 10 to 24% by mass of nickel, and carbon.
Titanium as an additive element is added so that the mass ratio of titanium content to carbon content (Ti mass / C mass) is in the range of 10 to 30 and the intergranular corrosion resistance is improved. Corrosion resistant austenitic stainless steel.
前記添加元素としてのチタンの含有量が０．１質量％以上１．０質量％以下であることを特徴とする耐食性オーステナイト系ステンレス鋼。 The corrosion-resistant austenitic stainless steel according to claim 1,
A corrosion-resistant austenitic stainless steel, wherein the content of titanium as the additive element is 0.1% by mass or more and 1.0% by mass or less.
チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が１０〜１５の範囲であることを特徴とする耐食性オーステナイト系ステンレス鋼。 The corrosion-resistant austenitic stainless steel according to claim 1 or 2,
A corrosion-resistant austenitic stainless steel, wherein the mass ratio of titanium content to carbon content (Ti mass / C mass) is in the range of 10-15.
冷間圧延加工と、当該冷間圧延加工後に行う加熱工程と、当該加熱工程後に行う冷却工程とからなる処理工程を、少なくとも２回施したことを特徴とする耐食性オーステナイト系ステンレス鋼。 The corrosion-resistant austenitic stainless steel according to any one of claims 1 to 3,
A corrosion-resistant austenitic stainless steel, which has been subjected to at least two treatment steps comprising a cold rolling process, a heating process performed after the cold rolling process, and a cooling process performed after the heating process.
前記冷間圧延工程の圧延率が３０％以上、前記加熱工程の加熱処理温度が８００℃以上１０００℃以下、前記冷却工程の冷却速度が１℃／秒以上５０℃／秒以下であることを特徴とする耐食性オーステナイト系ステンレス鋼。 The corrosion-resistant austenitic stainless steel according to claim 4,
The rolling rate of the cold rolling step is 30% or more, the heat treatment temperature of the heating step is 800 ° C. or higher and 1000 ° C. or lower, and the cooling rate of the cooling step is 1 ° C./second or higher and 50 ° C./second or lower. Corrosion resistant austenitic stainless steel.
結晶粒径が１〜７０μｍの範囲にあることを特徴とする耐食性オーステナイト系ステンレス鋼。 The corrosion-resistant austenitic stainless steel according to any one of claims 1 to 5,
A corrosion-resistant austenitic stainless steel having a crystal grain size in the range of 1 to 70 µm.
前記チタンの代わりに、ニオブ又はジルコニウムを添加元素として用いたことを特徴とする耐食性オーステナイト系ステンレス鋼。 The corrosion-resistant austenitic stainless steel according to any one of claims 1 to 6,
A corrosion-resistant austenitic stainless steel using niobium or zirconium as an additive element instead of titanium.
添加元素としてのチタンを、チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が１０〜３０の範囲となるように添加することによって耐粒界腐食特性を向上させることを特徴とする耐食性オーステナイト系ステンレス鋼の製造方法。 A method for producing a corrosion-resistant austenitic stainless steel containing 14 to 25% by mass of chromium, 10 to 24% by mass of nickel, and containing carbon,
It is characterized in that the intergranular corrosion resistance is improved by adding titanium as an additive element so that the mass ratio of titanium content to carbon content (Ti mass / C mass) is in the range of 10-30. A method for producing corrosion-resistant austenitic stainless steel.
前記添加元素としてのチタンの含有量が０．１質量％以上１．０質量％以下であることを特徴とする耐食性オーステナイト系ステンレス鋼の製造方法。 A method for producing a corrosion-resistant austenitic stainless steel according to claim 8,
A method for producing a corrosion-resistant austenitic stainless steel, wherein the content of titanium as the additive element is 0.1% by mass or more and 1.0% by mass or less.
チタン含有量の炭素含有量に対する質量比（Ｔｉ質量／Ｃ質量）が１０〜１５の範囲であることを特徴とする耐食性オーステナイト系ステンレス鋼の製造方法。 A method for producing a corrosion-resistant austenitic stainless steel according to claim 8 or 9,
A method for producing a corrosion-resistant austenitic stainless steel, wherein the mass ratio of titanium content to carbon content (Ti mass / C mass) is in the range of 10-15.
冷間圧延加工と、当該冷間圧延加工後に行う加熱工程と、当該加熱工程後に行う冷却工程とからなる処理工程を、少なくとも２回施すことを特徴とする耐食性オーステナイト系ステンレス鋼の製造方法。 A method for producing a corrosion-resistant austenitic stainless steel according to any one of claims 8 to 10,
A method for producing a corrosion-resistant austenitic stainless steel, characterized by performing at least twice a cold rolling process, a heating process performed after the cold rolling process, and a cooling process performed after the heating process.
前記冷間圧延工程の圧延率が３０％以上、前記加熱工程の加熱処理温度が８００℃以上１０００℃以下、前記冷却工程の冷却速度が１℃／秒以上５０℃／秒以下であることを特徴とする耐食性オーステナイト系ステンレス鋼の製造方法。 A method for producing a corrosion-resistant austenitic stainless steel according to claim 11,
The rolling rate of the cold rolling step is 30% or more, the heat treatment temperature of the heating step is 800 ° C. or higher and 1000 ° C. or lower, and the cooling rate of the cooling step is 1 ° C./second or higher and 50 ° C./second or lower. A method for producing a corrosion-resistant austenitic stainless steel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009016887A JP2010174308A (en) | 2009-01-28 | 2009-01-28 | Corrosion-resistant austenitic stainless steel and manufacturing method therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2009016887A JP2010174308A (en) | 2009-01-28 | 2009-01-28 | Corrosion-resistant austenitic stainless steel and manufacturing method therefor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2010174308A true JP2010174308A (en) | 2010-08-12 |
Family
ID=42705555
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2009016887A Pending JP2010174308A (en) | 2009-01-28 | 2009-01-28 | Corrosion-resistant austenitic stainless steel and manufacturing method therefor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2010174308A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113881830A (en) * | 2021-09-29 | 2022-01-04 | 太原理工大学 | Method for improving intergranular corrosion resistance of super austenitic stainless steel |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5747850A (en) * | 1980-09-01 | 1982-03-18 | Kawasaki Steel Corp | Austenite stainless steel with superior chloride stress corrosion cracking resistance |
| JPS59110767A (en) * | 1982-12-14 | 1984-06-26 | Sumitomo Metal Ind Ltd | Austenite stainless steel |
| JPS63259055A (en) * | 1987-04-17 | 1988-10-26 | Hitachi Ltd | Austenitic stainless steel |
| JP2005023343A (en) * | 2003-06-30 | 2005-01-27 | Sumitomo Metal Ind Ltd | Austenitic stainless steel pipe for atomic power |
| JP2005171278A (en) * | 2003-12-08 | 2005-06-30 | Toshiba Corp | Steel material and its manufacturing method |
| JP2007031803A (en) * | 2005-07-29 | 2007-02-08 | Hitachi Ltd | Highly corrosion-resistant reactor core material |
| JP2008063602A (en) * | 2006-09-05 | 2008-03-21 | Toshiba Corp | Corrosion resistant austenitic alloy and its production method |
-
2009
- 2009-01-28 JP JP2009016887A patent/JP2010174308A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5747850A (en) * | 1980-09-01 | 1982-03-18 | Kawasaki Steel Corp | Austenite stainless steel with superior chloride stress corrosion cracking resistance |
| JPS59110767A (en) * | 1982-12-14 | 1984-06-26 | Sumitomo Metal Ind Ltd | Austenite stainless steel |
| JPS63259055A (en) * | 1987-04-17 | 1988-10-26 | Hitachi Ltd | Austenitic stainless steel |
| JP2005023343A (en) * | 2003-06-30 | 2005-01-27 | Sumitomo Metal Ind Ltd | Austenitic stainless steel pipe for atomic power |
| JP2005171278A (en) * | 2003-12-08 | 2005-06-30 | Toshiba Corp | Steel material and its manufacturing method |
| JP2007031803A (en) * | 2005-07-29 | 2007-02-08 | Hitachi Ltd | Highly corrosion-resistant reactor core material |
| JP2008063602A (en) * | 2006-09-05 | 2008-03-21 | Toshiba Corp | Corrosion resistant austenitic alloy and its production method |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113881830A (en) * | 2021-09-29 | 2022-01-04 | 太原理工大学 | Method for improving intergranular corrosion resistance of super austenitic stainless steel |
| CN113881830B (en) * | 2021-09-29 | 2022-11-18 | 太原理工大学 | Method for improving intergranular corrosion resistance of super austenitic stainless steel |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Lopes et al. | A short review on welding and joining of high entropy alloys | |
| JP4099493B2 (en) | Zirconium alloy composition with excellent creep resistance | |
| Mo et al. | High temperature aging and corrosion study on alloy 617 and alloy 230 | |
| JP4616772B2 (en) | Austenitic stainless steel, method for producing the same, and structure using the same | |
| Arunkumar et al. | Effect of activated flux on the microstructure and mechanical properties of 9Cr-1Mo steel weld joint | |
| Kannan et al. | High temperature low cycle fatigue behaviour of P92 tungsten added 9Cr steel | |
| Shamsolhodaei et al. | Enhancement of mechanical and functional properties of welded NiTi by controlling nickel vapourisation | |
| TW200951988A (en) | A spacer grid | |
| JP2009079240A (en) | Austenitic stainless steel and producing method therefor, and structural material and piping in nuclear reactor | |
| JP2017145429A (en) | α+β TYPE TITANIUM ALLOY MEMBER AND MANUFACTURING METHOD THEREFOR | |
| JP2014181383A (en) | High corrosion resistance high strength stainless steel, structure in atomic furnace and manufacturing method of high corrosion resistance high strength stainless steel | |
| JP4062190B2 (en) | Austenitic stainless steel pipe for nuclear power | |
| JP2010275569A (en) | Austenitic stainless steel and method of manufacturing the same | |
| JP2010174308A (en) | Corrosion-resistant austenitic stainless steel and manufacturing method therefor | |
| JP2009287104A (en) | Thin sheet of austenitic stainless steel and manufacturing method therefor | |
| Wei et al. | Microstructure evolution and mechanical properties of 316H weld metal during aging | |
| JP2010133024A (en) | Austenitic high purity iron alloy having excellent high temperature property | |
| CN106399800B (en) | A kind of austenitic heat-resistance steel and its heat treatment process | |
| CN101532075A (en) | Method of increasing resistance to stress corrosion cracking of austenitic stainless steels | |
| JP2014005509A (en) | Highly corrosion-resistant austenitic stainless steel and weld joint structure | |
| JP2013208627A (en) | HIGH CORROSION RESISTANT Ni-BASED WELD METAL, WELDED STRUCTURE USING THE SAME, AND NUCLEAR POWER PLANT | |
| JP2008063602A (en) | Corrosion resistant austenitic alloy and its production method | |
| Khandelwal et al. | Influence of soaking temperature and time on microstructure and mechanical properties of water quenched Zr–2.5 Nb alloy | |
| Kearns et al. | Reducing heat tint effects on the corrosion resistance of austenitic stainless alloys | |
| JP2007031803A (en) | Highly corrosion-resistant reactor core material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Effective date: 20110117 Free format text: JAPANESE INTERMEDIATE CODE: A621 |
|
| RD02 | Notification of acceptance of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7422 Effective date: 20120614 |
|
| A977 | Report on retrieval |
Effective date: 20120912 Free format text: JAPANESE INTERMEDIATE CODE: A971007 |
|
| A131 | Notification of reasons for refusal |
Effective date: 20121023 Free format text: JAPANESE INTERMEDIATE CODE: A131 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20121217 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20130402 |