JP5098403B2 - Ferritic stainless steel sheet that hardly causes rough surface during bending, and method for producing the same - Google Patents
Ferritic stainless steel sheet that hardly causes rough surface during bending, and method for producing the same Download PDFInfo
- Publication number
- JP5098403B2 JP5098403B2 JP2007103533A JP2007103533A JP5098403B2 JP 5098403 B2 JP5098403 B2 JP 5098403B2 JP 2007103533 A JP2007103533 A JP 2007103533A JP 2007103533 A JP2007103533 A JP 2007103533A JP 5098403 B2 JP5098403 B2 JP 5098403B2
- Authority
- JP
- Japan
- Prior art keywords
- less
- steel sheet
- stainless steel
- ferritic stainless
- average diameter
- 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.)
- Active
Links
Landscapes
- Metal Rolling (AREA)
- Heat Treatment Of Sheet Steel (AREA)
Description
本発明は、フェライト系ステンレス鋼板、特に、曲げ加工時に肌荒れの発生し難いフェライト系ステンレス鋼板およびその製造方法に関する。 The present invention relates to a ferritic stainless steel sheet, and more particularly to a ferritic stainless steel sheet that hardly causes rough skin during bending and a method for manufacturing the same.
フェライト系ステンレス鋼板は、家電製品、厨房器具、電子機器、建材など幅広い分野で用いられている。このフェライト系ステンレス鋼板では、C、Nを低減するとともに、TiやNbを添加してC、Nを析出させて高r値化を図って、優れた加工性が実現されている。 Ferritic stainless steel sheets are used in a wide range of fields such as home appliances, kitchen appliances, electronic equipment, and building materials. In this ferritic stainless steel sheet, excellent workability is realized by reducing C and N and adding Ti and Nb to precipitate C and N to increase the r value.
従来より、建材の分野では、2.0mmを超える板厚の冷延鋼板を曲げ加工して製造される部材が多いが、それにフェライト系ステンレス鋼板を適用すると、曲げ加工部に肌荒れが発生し、部材の外観を損なうことが問題になっている。この肌荒れは、特許文献1や特許文献2に記載されたリジング性に優れたフェライト系ステンレス鋼板でも認められることから、粗大な柱状晶の凝固組織に起因するリジングとは異なる。 Conventionally, in the field of building materials, many parts are manufactured by bending cold-rolled steel sheets with a thickness of over 2.0 mm. It has become a problem to impair the appearance. This rough surface is also observed in the ferritic stainless steel sheet having excellent ridging properties described in Patent Document 1 and Patent Document 2, and is different from ridging caused by the solidified structure of coarse columnar crystals.
このようなフェライト系ステンレス鋼板に見られる曲げ加工時の肌荒れについては、報告も少なく、わずかに特許文献3に、結晶粒径dと加工時の真歪量εとがd<6/εの関係を満足するように加工時の真歪量εを制御して、フェライト系ステンレス鋼板の加工時の肌荒れを防止する方法が開示されているに過ぎない。そして、こうした方法に相応しいフェライト系ステンレス鋼板としては、mass%で、C:0.001〜0.01%、Si:0.01〜0.3%、Mn:0.01〜0.3%、P:0.01〜0.04%、S:0.0001〜0.01%、Cr:15〜25%、N:0.001〜0.02%、B:0.0003〜0.005%、Ti:0.05〜0.3%、Al:0.005〜0.1%、Mg:0.0002〜0.005%、残部Feおよび不可避的不純物からなる成分組成のフェライト系ステンレス鋼板が提案されている。
しかしながら、特許文献3に記載の方法では、主にプレス成形による肌荒れを対象としている。プレス成形による肌荒れは集合組織を原因としており、曲げの肌荒れとは発生機構が異なっている。したがって、特許文献3に記載の方法によっても肌荒れが発生する場合がある。 However, the method described in Patent Document 3 mainly targets rough skin caused by press molding. Rough skin due to press molding is caused by a texture, and the generation mechanism is different from rough skin. Therefore, rough skin may occur even by the method described in Patent Document 3.
本発明は、このような事情に鑑みなされたもので、曲げ加工時に肌荒れの発生し難いフェライト系ステンレス鋼板およびその製造方法を提供することを目的とする。 The present invention has been made in view of such circumstances, and an object of the present invention is to provide a ferritic stainless steel sheet that hardly causes rough skin during bending and a method for manufacturing the same.
本発明者らは、フェライト系ステンレス鋼板を曲げ加工した時に発生する肌荒れを軽減する目的で、鋼の成分組成、組織に着目し、肌荒れの発生機構について検討を行った結果、以下のことを見出した。 The inventors of the present invention have found the following as a result of investigating the mechanism of occurrence of rough skin, focusing on the composition and structure of steel for the purpose of reducing the rough skin that occurs when bending ferritic stainless steel sheets. It was.
i)曲げ加工部のフェライト粒径と肌荒れ深さに相関が認められ、フェライト粒の平均径が30μmを超えると肌荒れ深さが大きくなり、目に見えて肌荒れが顕著になる。 i) There is a correlation between the ferrite grain size and the rough skin depth in the bent part, and when the average diameter of the ferrite grains exceeds 30 μm, the rough skin depth increases and the rough skin becomes visible.
ii)平均径が0.5〜20μmのTiCを析出させると、曲げ加工時にTiCの表面から転位が発生し、加工硬化が促進され、曲げ加工部の歪が分散されて肌荒れ深さが小さくなる。 ii) When TiC having an average diameter of 0.5 to 20 μm is precipitated, dislocations are generated from the surface of TiC during bending, work hardening is promoted, strain in the bent portion is dispersed, and the rough skin depth is reduced.
本発明は、このような知見に基づきなされたもので、mass%で、C:0.001〜0.02%、Si:0.05〜0.5%、Mn:0.5%以下、P:0.04%以下、S:0.01%以下、Al:0.1%以下、Cr:20〜24%、Cu:0.3〜0.8%、Ni:0.5%以下、Ti:0.20〜0.5%、N:0.001〜0.02%を含有し、残部がFeおよび不可避的不純物からなる成分組成を有し、フェライト粒の平均径が30μm以下であり、平均径が0.5〜2.0μmのTiCが析出していることを特徴とする曲げ加工時に肌荒れの発生し難いフェライト系ステンレス鋼板を提供する。 The present invention was made based on such findings, in mass%, C: 0.001 to 0.02%, Si: 0.05 to 0.5%, Mn: 0.5% or less, P: 0.04% or less, S: 0.01% or less , Al: 0.1% or less, Cr: 20-24%, Cu: 0.3-0.8%, Ni: 0.5% or less, Ti: 0.20-0.5%, N: 0.001-0.02%, the balance being Fe and inevitable Ferritic stainless steel, which has a component composition consisting of impurities, has an average diameter of ferrite grains of 30 μm or less, and has TiC precipitated with an average diameter of 0.5 to 2.0 μm, which hardly causes rough skin during bending. Provide steel sheet.
本発明のフェライト系ステンレス鋼板は、上記の成分組成を有する鋼を熱間圧延するとき、少なくとも1パスを40%以上の圧下率で粗圧延を行い、770℃以下の仕上温度で仕上圧延を行って熱延鋼板とし、前記熱延鋼板を450℃以下の巻取温度で巻取ることを特徴とする製造方法により製造できる。 The ferritic stainless steel sheet of the present invention, when hot-rolling steel having the above component composition, performs rough rolling at a rolling reduction of at least 40% at least one pass, and finish rolling at a finishing temperature of 770 ° C. or less. Thus, a hot-rolled steel sheet can be obtained, and the hot-rolled steel sheet can be wound at a coiling temperature of 450 ° C. or lower.
本発明により、曲げ加工時に肌荒れの発生し難いフェライト系ステンレス鋼板を製造できるようになった。本発明のフェライト系ステンレス鋼板は、曲げ加工により製造される建材に好適である。 According to the present invention, it is possible to produce a ferritic stainless steel sheet that hardly causes rough skin during bending. The ferritic stainless steel sheet of the present invention is suitable for building materials manufactured by bending.
以下に、本発明の詳細について説明する。 Details of the present invention will be described below.
1)成分組成(以下の「%」は「mass%」を表す。)
C:0.001〜0.02%
Cは、加工性と耐食性を劣化させるので可能な限り少ない方が好ましいが、Tiと結合してTiCを形成し、曲げ加工時の加工硬化を促進するには、その量を0.001%以上にする必要がある。一方、その量が0.02%を超えると、他の析出物と複合して粗大化し、曲げ加工時の加工硬化の促進が期待できなくなる。よって、C量は0.001〜0.02%とする。
1) Component composition ("%" below represents "mass%")
C: 0.001 ~ 0.02%
Since C degrades workability and corrosion resistance, it is preferable to reduce it as much as possible. However, in order to form TiC by combining with Ti and promote work hardening during bending, the amount should be 0.001% or more. There is a need. On the other hand, if the amount exceeds 0.02%, it is combined with other precipitates to become coarse, and work hardening during bending cannot be expected to be accelerated. Therefore, the C amount is 0.001 to 0.02%.
Si:0.05〜0.5%
Siは、脱酸剤として有用な元素である。しかし、その量が0.05%未満では十分な脱酸効果が得られず、酸化物が多量に鋼中に分散し、曲げ加工性が劣化する。一方、その量が0.5%を超えると鋼が硬質化し、加工性の劣化を招く。よって、Si量は0.05〜0.5%とする。
Si: 0.05-0.5%
Si is an element useful as a deoxidizer. However, if the amount is less than 0.05%, a sufficient deoxidation effect cannot be obtained, and a large amount of oxide is dispersed in the steel, so that bending workability is deteriorated. On the other hand, if the amount exceeds 0.5%, the steel becomes hard and the workability is deteriorated. Therefore, the Si content is 0.05 to 0.5%.
Mn:0.5%以下
Mn量が0.5%を超えると固溶硬化により加工性を損なう上に、MnSとして析出し耐食性を低下させる。よって、Mn量は0.5%以下とするが、少ない程好ましい。
Mn: 0.5% or less
If the amount of Mn exceeds 0.5%, the workability is impaired by solid solution hardening, and MnS precipitates to lower the corrosion resistance. Therefore, the amount of Mn is set to 0.5% or less, but it is preferable that the amount is smaller.
P:0.04%以下
P量が0.04%を超えると、Mn同様、固溶硬化により加工性を損なうとともに、結晶粒界に偏析して熱間加工性を劣化させる。よって、P量は0.04%以下とするが、少ない程好ましい。
P: 0.04% or less
If the amount of P exceeds 0.04%, the workability is impaired by solid solution hardening, as is the case with Mn, and segregates at the grain boundaries to deteriorate the hot workability. Therefore, the amount of P is set to 0.04% or less, but the smaller the amount, the better.
S:0.01%以下
S量が0.01%を超えると、ステンレス鋼の耐食性を低下させる。よって、S量は0.01%以下とするが、少ない程好ましい。
S: 0.01% or less
When the amount of S exceeds 0.01%, the corrosion resistance of the stainless steel is lowered. Therefore, the amount of S is set to 0.01% or less, but it is preferably as small as possible.
Al:0.1%以下
Alは、脱酸のために有用な元素であるが、その量が0.1%を超えると非金属介在物が増加し、曲げ加工性が劣化する。よって、Al量は0.1%以下とする。
Al: 0.1% or less
Al is an element useful for deoxidation, but if its amount exceeds 0.1%, nonmetallic inclusions increase and bending workability deteriorates. Therefore, the Al content is 0.1% or less.
Cr:20〜24%
Crは、フェライト系ステンレス鋼の耐食性を決める重要な元素であり、十分な耐食性を得るには、その量を20%以上にする必要がある。しかし、その量が24%を超えるとσ相が生成し易くなりプレス加工性が低下する。よって、Cr量は20〜24%とする。
Cr: 20-24%
Cr is an important element that determines the corrosion resistance of ferritic stainless steel. To obtain sufficient corrosion resistance, its amount needs to be 20% or more. However, when the amount exceeds 24%, a σ phase is easily generated and press workability is deteriorated. Therefore, the Cr content is 20 to 24%.
Cu:0.3〜0.8%
Cuは、アノード反応による地鉄の溶解を低減する効果があり、特に耐隙間腐食性の向上に有用な元素である。それには、その量を0.3%以上にする必要がある。しかし、その量が0.8%を超えると熱間加工性が低下し、表面疵が発生し易くなる。よって、Cu量は0.3〜0.8%とする。
Cu: 0.3-0.8%
Cu has an effect of reducing dissolution of the base iron due to the anode reaction, and is an element particularly useful for improving crevice corrosion resistance. For that, the amount needs to be 0.3% or more. However, when the amount exceeds 0.8%, the hot workability is lowered and surface defects are likely to occur. Therefore, the Cu amount is set to 0.3 to 0.8%.
Ni:0.5%以下
Niは、耐食性を向上させる効果があるが、その量が0.05%を超えると鋼が硬質化する。よって、Ni量は0.5%以下とする。
Ni: 0.5% or less
Ni has the effect of improving the corrosion resistance, but if its amount exceeds 0.05%, the steel becomes hard. Therefore, the Ni content is 0.5% or less.
Ti:0.20〜0.5%
Tiは、本発明の主要な元素の一つであり、C、Nを固定してCr炭窒化物の析出による鋭敏化、すなわちCr炭窒化物が析出することでその周囲のCr濃度が減少して耐食性が低下し、腐食の起点となることを防ぐ効果がある。Tiを含む析出物としては、TiN、Ti4C2S2、TiC、TiSなどが知られているが、TiN、Ti4C2S2は粗大な析出物となり易く、TiC、TiSは微細な析出物となり易い。本発明では、ある大きさの範囲のTiCを分散析出させることで粒界移動を阻止し、フェライト粒を微細化している。また、曲げ加工を行うと、よりやわらかい部分や応力の集中する部分から変形が起こるが、TiCが分散析出している場合は、変形によりこれら析出物から生じた転位で加工硬化が起こり、周囲より硬くなる。したがって、変形の起こる個所がよりやわらかい部分へと順次移動していくため、座屈などの局所的な変形が起こらず、曲げ部分が均一に加工されるため、肌荒れが低減されることになる。こうしたTiの効果を得るには、その量を0.20%以上にする必要がある。一方、その量が0.5%を超えると粗大なTi4C2S2の析出が起こり易くなり、こうした効果が得られなくなる。よって、Ti量は0.20〜0.5%とする。
Ti: 0.20-0.5%
Ti is one of the main elements of the present invention. C and N are fixed and sensitization is caused by the precipitation of Cr carbonitride, that is, Cr carbonitride is precipitated, thereby reducing the surrounding Cr concentration. Corrosion resistance is reduced, and it has the effect of preventing starting of corrosion. TiN, Ti 4 C 2 S 2 , TiC, and TiS are known as Ti-containing precipitates, but TiN and Ti 4 C 2 S 2 tend to be coarse precipitates, and TiC and TiS are fine. It tends to be a precipitate. In the present invention, grain boundaries are prevented from moving by dispersing and precipitating TiC in a certain size range, and ferrite grains are refined. Also, when bending is performed, deformation occurs from softer parts and stress concentrated parts, but when TiC is dispersed and precipitated, work hardening occurs due to dislocations generated from these precipitates due to deformation, and from the surroundings It becomes hard. Therefore, since the location where the deformation occurs is sequentially moved to a softer portion, local deformation such as buckling does not occur, and the bent portion is processed uniformly, so that rough skin is reduced. In order to obtain such Ti effects, the amount needs to be 0.20% or more. On the other hand, if the amount exceeds 0.5%, coarse Ti 4 C 2 S 2 precipitates easily, and such an effect cannot be obtained. Therefore, the Ti amount is set to 0.20 to 0.5%.
N:0.001〜0.02%
Nは、C同様、加工性と耐食性を劣化させるとともに、粗大なTiNを析出し、TiCの形成を阻害するため、その量を0.02%以下にする必要がある。一方、その量が0.001%未満になるとフェライト粒の増大を招く。よって、N量は0.001〜0.02%とする。
N: 0.001 to 0.02%
N, like C, deteriorates workability and corrosion resistance, precipitates coarse TiN, and inhibits the formation of TiC, so its amount needs to be 0.02% or less. On the other hand, when the amount is less than 0.001%, ferrite grains increase. Therefore, the N content is 0.001 to 0.02%.
2)組織
2-1)フェライト粒径(フェライト粒の平均径):30μm以下
上述したように、曲げ加工部の肌荒れはフェライト粒径と相関があり、フェライト粒が大きくなると肌荒れ深さが大きくなり、肌荒れが顕著になる。その理由については明らかになっていないが、次のように推測される。すなわち、曲げ加工を行った際、フェライト粒は引張応力を受けて、球形から扁平な楕円球形に変形する。その変形によって隣り合うフェライト粒の間に溝ができるため、肌荒れが発生する。一定量の曲げ加工を行った場合、楕円球形に変形したフェライト粒の長径と短径の比は、フェライト粒の大きさによらず一定である。肌荒れ深さは変形後の楕円球形の短径の大きさに比例し、変形後の楕円球形の短径の大きさは変形前のフェライト粒径に比例する。したがって、肌荒れの深さはフェライト粒径に依存し、フェライト粒径が大きいほど曲げ部の肌荒れ深さが大きくなる。特に、フェライト粒の平均径が30μmを超えると肌荒れ深さが大きくなり、目に見えて肌荒れが顕著になり、加工部材の外観を著しく損なうので、フェライト粒の平均径は30μm以下とする。
2) Organization
2-1) Ferrite grain size (average diameter of ferrite grains): 30 μm or less As described above, the rough surface of the bent part has a correlation with the ferrite grain size, and the larger the ferrite grain, the greater the rough skin depth. Become prominent. The reason is not clear, but is presumed as follows. That is, when the bending process is performed, the ferrite grains receive a tensile stress and are deformed from a spherical shape to a flat elliptical spherical shape. Due to the deformation, a groove is formed between adjacent ferrite grains, resulting in rough skin. When a certain amount of bending is performed, the ratio of the major axis to the minor axis of the ferrite grains deformed into an elliptical sphere is constant regardless of the size of the ferrite grains. The rough skin depth is proportional to the size of the minor axis of the elliptical sphere after deformation, and the size of the minor axis of the elliptical sphere after deformation is proportional to the ferrite grain size before transformation. Therefore, the depth of rough skin depends on the ferrite grain size, and the larger the ferrite grain size, the larger the rough skin depth of the bent part. In particular, when the average diameter of the ferrite grains exceeds 30 μm, the rough skin depth becomes large, the rough skin becomes noticeable, and the appearance of the processed member is remarkably impaired. Therefore, the average diameter of the ferrite grains is 30 μm or less.
2-2)TiCの平均径:0.5〜2.0μm
上述したように、ある大きさの範囲のTiCを分散析出させると、粒界移動を阻止してフェライト粒を微細化できるとともに、曲げ加工時にTiCから生じた転位により加工硬化を促進して均一に加工されるため、曲げ加工部の肌荒れが低減される。このような効果をもたせるには、TiCの大きさを0.5〜2.0μmとする必要がある。
2-2) Average diameter of TiC: 0.5-2.0μm
As described above, when TiC in a certain size range is dispersed and precipitated, ferrite particles can be refined by preventing grain boundary migration, and work hardening is promoted uniformly by dislocations generated from TiC during bending. Since it is processed, the rough surface of the bent portion is reduced. In order to have such an effect, the size of TiC needs to be 0.5 to 2.0 μm.
3)製造条件
3-1)熱間圧延時の粗圧延:少なくとも1パスの圧下率が40%以上
熱間圧延時の粗圧延において、少なくとも1パスの圧下率を40%以上とすると、多くの歪が導入され熱延鋼板のフェライト粒の微細化が図れ、その結果、後述する仕上温度や巻取温度による熱延鋼板のフェライト粒の微細化と前述したTiCの分散析出との相乗効果により冷間圧延-延焼鈍後のフェライト粒の平均径を30μm以下にできる。
3) Manufacturing conditions
3-1) Rough rolling during hot rolling: at least one pass rolling reduction is 40% or more In rough rolling during hot rolling, if at least one pass rolling reduction is 40% or more, many strains are introduced. As a result, the fineness of ferrite grains in hot-rolled steel sheets can be reduced. The average diameter of the ferrite grains after annealing can be reduced to 30 μm or less.
3-2)仕上温度:770℃以下
770℃以下の低温で熱間圧延を終えることで圧延中の回復、再結晶が抑制され、より多くの歪を導入でき、上述したような相乗効果により冷間圧延-延焼鈍後のフェライト粒の平均径を30μm以下にできる。
3-2) Finishing temperature: 770 ° C or less
By finishing hot rolling at a low temperature of 770 ° C or lower, recovery and recrystallization during rolling can be suppressed, and more strain can be introduced. The average diameter can be 30 μm or less.
3-3)巻取温度:450℃以下
巻取温度を450℃以下にすると、巻取り後の余熱によるフェライト粒の成長を抑制でき、上述したような相乗効果により冷間圧延-延焼鈍後のフェライト粒の平均径を30μm以下にできる。
3-3) Winding temperature: 450 ° C or less When the winding temperature is set to 450 ° C or less, the growth of ferrite grains due to the residual heat after winding can be suppressed. The average diameter of the ferrite grains can be reduced to 30 μm or less.
上記以外の製造条件は、特に限定する必要はなく、通常のフェライト系ステンレス鋼板の製造条件と同様でよいが、次の条件で製造することが好ましい。すなわち、上記成分組成のスラブを、1150〜1200℃に加熱後、最終パスの圧下率を40%として粗圧延を行い、770℃以下の仕上温度で仕上圧延を行い、板厚2.5〜6mmの熱延鋼板とし、20℃/s以上の冷却速度で450℃以下の温度まで冷却し、巻取る。その後、熱延鋼板を800〜1000℃の温度で焼鈍し、酸洗後冷間圧延し、焼鈍-酸洗を行い、フェライト系ステンレス鋼板が製造される。なお、最終焼鈍では、フェライト粒の粗大化を抑制するために、850℃以上となる時間を1min以内とすることが望ましい。 Manufacturing conditions other than those described above are not particularly limited, and may be the same as the manufacturing conditions of a normal ferritic stainless steel sheet, but are preferably manufactured under the following conditions. That is, after heating the slab having the above composition to 1150 to 1200 ° C., rough rolling was performed at a final pass reduction ratio of 40%, finish rolling was performed at a finishing temperature of 770 ° C. or less, and a thickness of 2.5 to 6 mm was applied. A rolled steel sheet is cooled to a temperature of 450 ° C. or lower at a cooling rate of 20 ° C./s or higher and wound. Thereafter, the hot-rolled steel sheet is annealed at a temperature of 800 to 1000 ° C., cold-rolled after pickling, and annealed-pickled to produce a ferritic stainless steel sheet. In the final annealing, in order to suppress the coarsening of the ferrite grains, it is desirable that the time for 850 ° C. or higher is within 1 min.
表1に示す成分組成を有する鋼No.1〜21を溶製した後、1170℃に加熱後、表2に示す条件で熱間圧延して熱延鋼板を製造した。このとき、粗圧延は9パスで行い、最終パス(9パス目)の圧下率を表2のように変化させた。その後、熱延鋼板を800〜1000℃で焼鈍し、酸洗後冷間圧延して板厚0.8mmの冷延鋼板とし、850〜1000℃で焼鈍を行い、鋼板No.1〜30を作製した。そして、希王水によりエッチング後、切断法によりフェライト粒の平均径を求めた。また、SEM(走査型電子顕微鏡)によりTiCを観察し、任意に50個選んで平均径を求めた。さらに、幅20mm、長さ70mmの試料を採取し、両面を600番の研磨紙で研磨し、10mmRのポンチを用いて長さ方向の中央部をプレスし、180度の曲げ加工を行い、次の方法で肌荒れ深さを測定した。
肌荒れ深さ:曲げ部の断面を光学顕微鏡を用いて倍率25倍で観察し、凸部の頂点を結んだ直線から凹部へ引いた垂線のうち最も長い長さを肌荒れ深さとし、肌荒れ深さが30μm以下を肌荒れ良好(○)、30μm超えを肌荒れ不良(×)とした。
Steel Nos. 1 to 21 having the composition shown in Table 1 were melted, heated to 1170 ° C., and hot-rolled under the conditions shown in Table 2 to produce hot-rolled steel sheets. At this time, rough rolling was performed in 9 passes, and the rolling reduction in the final pass (9th pass) was changed as shown in Table 2. Then, the hot-rolled steel sheet was annealed at 800-1000 ° C., pickled and cold-rolled to obtain a cold-rolled steel sheet having a thickness of 0.8 mm, and annealed at 850-1000 ° C. to produce steel sheets No. 1-30. . And after etching with dilute aqua regia, the average diameter of ferrite grains was determined by a cutting method. Further, TiC was observed with a SEM (scanning electron microscope), and 50 were arbitrarily selected to obtain an average diameter. In addition, a sample with a width of 20 mm and a length of 70 mm was taken, both sides were polished with No. 600 abrasive paper, the center in the length direction was pressed using a 10 mmR punch, bent 180 degrees, and then The rough skin depth was measured by the method.
Rough skin depth: Observe the cross section of the bent part with an optical microscope at a magnification of 25 times, and the longest length of the perpendicular drawn from the straight line connecting the top of the convex part to the concave part is the rough skin depth. 30 μm or less was defined as good skin roughness (◯), and over 30 μm was defined as poor skin roughness (×).
結果を表2に示す。本発明例である鋼No.2〜4、6〜8、11〜13、15〜17、19〜21、23〜25、27〜28は、いずれも肌荒れ深さが30μm以下(○)であり、曲げ加工時に肌荒れが発生し難いことがわかる。 The results are shown in Table 2. Steel Nos. 2 to 4, 6 to 8, 11 to 13, 15 to 17, 19 to 21, 23 to 25, and 27 to 28, which are examples of the present invention, have a rough skin depth of 30 μm or less (◯). It can be seen that rough skin hardly occurs during bending.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2007103533A JP5098403B2 (en) | 2007-04-11 | 2007-04-11 | Ferritic stainless steel sheet that hardly causes rough surface during bending, and method for producing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2007103533A JP5098403B2 (en) | 2007-04-11 | 2007-04-11 | Ferritic stainless steel sheet that hardly causes rough surface during bending, and method for producing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2008260991A JP2008260991A (en) | 2008-10-30 |
| JP5098403B2 true JP5098403B2 (en) | 2012-12-12 |
Family
ID=39983687
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2007103533A Active JP5098403B2 (en) | 2007-04-11 | 2007-04-11 | Ferritic stainless steel sheet that hardly causes rough surface during bending, and method for producing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP5098403B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5375069B2 (en) * | 2008-12-15 | 2013-12-25 | Ｊｆｅスチール株式会社 | Ferritic stainless steel plate with excellent corrosion resistance on the shear end face |
| KR101322992B1 (en) * | 2010-12-09 | 2013-10-29 | 주식회사 포스코 | ferritic stainless steel with high surface quality and method of manufacturing it |
| JP6306353B2 (en) * | 2014-01-21 | 2018-04-04 | Ｊｆｅスチール株式会社 | Method for producing slab for ferritic stainless steel cold rolled steel sheet and method for producing ferritic stainless steel cold rolled steel sheet |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3809827B2 (en) * | 2002-06-17 | 2006-08-16 | Ｊｆｅスチール株式会社 | Ti-added ferritic stainless steel sheet and method for producing the same |
-
2007
- 2007-04-11 JP JP2007103533A patent/JP5098403B2/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| JP2008260991A (en) | 2008-10-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5196807B2 (en) | Ferritic stainless steel sheet excellent in formability with low roughness of processing surface and method for producing the same | |
| JP3409965B2 (en) | Austenitic stainless hot-rolled steel sheet excellent in deep drawability and method for producing the same | |
| JP5924459B1 (en) | Stainless steel for cold rolled steel | |
| JP4475352B2 (en) | Stainless steel sheet for parts and manufacturing method thereof | |
| KR101941065B1 (en) | Cold-rolled ferritic stainless steel sheet | |
| JP5219689B2 (en) | Ferritic stainless steel sheet with low surface roughness and manufacturing method thereof | |
| EP3438313A1 (en) | Nb-containing ferritic stainless steel sheet and manufacturing method therefor | |
| WO2017002148A1 (en) | Cold-rolled stainless steel sheet material, manufacturing method therefor, and cold-rolled steel sheet | |
| JP4682806B2 (en) | Ferritic stainless steel cold-rolled steel sheet excellent in press formability and manufacturing method thereof | |
| KR101850231B1 (en) | Ferritic stainless steel and method for producing same | |
| JP5098403B2 (en) | Ferritic stainless steel sheet that hardly causes rough surface during bending, and method for producing the same | |
| JP3932020B2 (en) | Ferritic stainless steel with excellent deep drawability and small in-plane anisotropy and method for producing the same | |
| JP6093063B1 (en) | High-strength stainless steel material excellent in workability and its manufacturing method | |
| JP3245356B2 (en) | Austenitic stainless cold-rolled steel sheet excellent in stretch formability and method for producing the same | |
| KR102590079B1 (en) | Ferritic stainless steel sheet and manufacturing method thereof | |
| JP3886864B2 (en) | Ferritic stainless steel cold-rolled annealed material excellent in secondary workability and manufacturing method thereof | |
| JP5151222B2 (en) | Method for producing ferritic stainless steel sheet with excellent corrosion resistance in the presence of chlorine bleach | |
| JP2001032054A (en) | Fe-Cr-Sx ALLOY EXCELLENT IN HIGH FREQUENCY CORE LOSS CHARACTERISTIC AND ITS PRODUCTION | |
| JP5375069B2 (en) | Ferritic stainless steel plate with excellent corrosion resistance on the shear end face | |
| KR101263612B1 (en) | Cold-rolled steel sheet with excellent formability, shape retentivity, and surface appearance and process for producing same | |
| JP3026540B2 (en) | Manufacturing method of stainless steel sheet | |
| JP7483049B2 (en) | Duplex stainless steel sheet, hot-rolled duplex stainless steel sheet, and method for manufacturing duplex stainless steel sheet | |
| JP7400707B2 (en) | Steel plate and its manufacturing method | |
| JP3923485B2 (en) | Manufacturing method of ferritic single-phase stainless steel with excellent deep drawability | |
| JP5338245B2 (en) | Stainless cold-rolled steel sheet with good strength-elongation balance and small ridging and method for producing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20100325 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20120301 |
|
| RD03 | Notification of appointment of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7423 Effective date: 20120321 |
|
| RD04 | Notification of resignation of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7424 Effective date: 20120327 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20120403 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20120531 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20120828 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20120910 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20151005 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 5098403 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |