JP4496659B2 - Martensitic stainless steel with excellent punchability - Google Patents
Martensitic stainless steel with excellent punchability Download PDFInfo
- Publication number
- JP4496659B2 JP4496659B2 JP2001090821A JP2001090821A JP4496659B2 JP 4496659 B2 JP4496659 B2 JP 4496659B2 JP 2001090821 A JP2001090821 A JP 2001090821A JP 2001090821 A JP2001090821 A JP 2001090821A JP 4496659 B2 JP4496659 B2 JP 4496659B2
- Authority
- JP
- Japan
- Prior art keywords
- quenching
- hardness
- stainless steel
- martensitic stainless
- amount
- 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.)
- Expired - Lifetime
Links
Images
Landscapes
- Heat Treatment Of Sheet Steel (AREA)
Description
【0001】
【発明の属する技術分野】
本発明は、例えば二輪車のディスクブレーキ材などの車輌部材や機械部材などの用途に好適な、焼入れたままで用いるマルテンサイト系ステンレス鋼に関し、必要な焼入れ硬度のほか、とくに焼き入れ前には優れた打ち抜き加工性を有するマルテンサイト系ステンレス鋼を提案するものである。なお、本発明にいう%は、特にことわらないかぎり、すべて質量%を意味するものとする。
【0002】
【従来の技術】
二輪車のディスクブレーキ材にはブレーキとしての性能を長期間維持するために耐摩耗性が必要である。この耐摩耗性は一般に硬度が高くなるに従い良好となるが、一方靱性は逆に低下する。耐摩耗性と靱性の両方を考慮して、ロックウエル硬度HRCで30〜40の範囲に制御される場合が多い。
従来、この用途に使用されるステンレス鋼としては、C;0.2 %のSUS420J1およびC;0.3 %のSUS420J2等の高Cマルテンサイト系ステンレス鋼か、低C高Mnマルテンサイト系ステンレス鋼が用いられてきた。
【0003】
しかし、上記SUS420J1、SUS420J2等の高Cマルテンサイト系ステンレス鋼では、焼入れ温度が変動したときの硬度の変動が大きいために、焼入れのみで所定の硬度を得るには極めて精度の高い熱処理管理が必要であった。また、仮に焼戻しにより焼入れ条件の管理を緩和できたとしても、焼戻しによって析出するCr炭窒化物の周囲に低Cr濃度の領域が生じて、耐食性が低下するという難点があった。
【0004】
一方、特公昭60−2380号に示されるような低C高Mnマルテンサイト系ステンレス鋼では、焼入れ温度に対する硬度の変動が緩和されるため、高Cマルテンサイト系ステンレス鋼におけるような過酷な熱処理条件の管理は不要となる。
しかし、この材料を用いてディスクブレーキなどの部材を製造する際に、焼鈍、酸洗の後、焼入れ前の打ち抜き加工工程で、打ち抜き型で剪断される近傍が塑性変形域に引きずり込まれて、「ダレ(垂れ下がり・反り上がりともいう)」(図3参照)になりやすく、加工精度を低下させるという問題が残されていた。打ち抜き部の縁辺部にダレが発生すると、外形の維持、他部材と摺動したときのビビリ防止等の必要性から、その後の工程で、平面平滑化のためにダレがなくなるまで切削・研摩作業を余分に行わなければならず、工数負荷の増大と歩止ロスを招くことになる。
【0005】
【発明が解決しようとする課題】
このように従来の低C高Mnマルテンサイト系ステンレス鋼は、焼入れ硬度の焼入れ温度依存性が小さいために熱処理管理が容易であると言う利点を有していたものの、一方では、焼入れ前の加工成形段階において、特に打ち抜き加工でダレが生じるという問題があった。
そこで、本発明は、従来技術が抱えているかかる問題を解消して、所定の焼入れ硬度が安定して得られるとともに、焼き入れ前における、打ち抜き加工性に優れたマルテンサイト系ステンレス鋼を提供することにある。
【0006】
【課題を解決するための手段】
本発明の要旨構成は以下のとおりである。
(1) 質量%で、C+N:0.04超〜0.10%、
Si:0.5 %以下、
Mn:1.0 〜2.5 %、
Cr:10.0超〜14.5%、
Cu:0.5 %以下、
Ni:0.5 %超〜1.50%
を含有し、残部はFeおよび不可避的不純物から成ることを特徴とする打ち抜き加工性に優れたマルテンサイト系ステンレス鋼。
【0007】
【発明の実施の形態】
以下、本発明のマルテンサイト系ステンレス鋼の成分組成を上記範囲に限定した理由について説明する。
C+N;0.04超〜0.10%
CおよびNは、いずれも硬度を高め、耐摩耗性を向上させるのに有効な元素であり、本発明のMn量範囲において、焼入れ時の硬度を30〜40HRCにするための(C+N)量は0.04%を超え0.10%以下の範囲である。
【0008】
Si;0.5 %以下
Siは、高温においてフェライトを生成させる元素であり、0.5 %を超えると焼入れ硬度を低下させるのみならず、靱性に悪影響を与えるので、その上限を0.50%とする。なお、Si量は少ないほど好ましい。
【0009】
Mn;1.0 〜2.5 %
Mnは、高温におけるδ−フェライトの生成を抑制するのに有効な元素である。1.0 %未満の含有量ではδ−フェライトを生成し、30〜40HRCの焼入れ硬度が得られなくなる。なお、30〜40HRCの焼入れ硬度を高(C+N)の成分系で達成しようとすると、適正(C+N)量の範囲が著しく狭くなるため、製造性が低下する。
Mn量が低すぎると、30〜40HRCの焼入れ硬度を得るための焼入れ熱処理の温度範囲が極端に狭少となるため、温度管理も難しくなるので、その下限を1.0 %とする。一方、Mn量が2.5 %を超えると、高温での耐酸化性が低下し、鋼板の製造工程におけるスケール生成量が多くなり、板面に肌荒を生じて鋼板の寸法精度を著しく低下させるので、その上限を2.5 %に限定する。なお、安定した焼入れ硬度を得るには、Mnを1.2 〜2.5 %の範囲で含有させることが望ましい。
【0010】
Cr;10.0超〜14.5%
Crは、耐食性を保持するために、10.0%超の含有量が不可欠である。しかし、14.5%を超えると、Mn、NiおよびCuのそれぞれ上限量を添加しても、850 〜1050℃の焼入れ温度範囲でδ−フェライトが出現するようになり、30〜40HRCの焼入れ硬度が得られなくなる。よってCr含有量は10.0超〜14.5%の範囲とする。
【0011】
Cu;0.5 %以下
Cuは、Mnと同様に、高温においてδフェライトの生成を防止するのに有効である。本発明においてはMn量1.0 〜2.5 %添加によってその目的を達せられるが、必要に応じて添加することができる。その際、過度に添加すると、高温での熱間圧延時に表面疵を発生し、歩留を低下させるので、0.5 %以下の範囲で含有させる。
【0012】
Ni;0.5 %超〜1.50%
Niは、本発明において重要な元素であり、0.5 %超〜1.50%の範囲で含有させる必要がある。
低炭素マルテンサイト系ステンレス鋼(ベース成分:0.05%C、0.3 %Si、1.5 %Mn、12.5%Cr、0.1 %Cu、0.01%N)において、Ni含有量と熱延焼鈍板のロックウェル硬さ(HRB)との関係を調べたところ、図1の結果が得られた。図1から、Ni含有量が0.5 %超〜1.50%の範囲では、Ni含有量とともに硬さが上昇していることがわかる。
次に、発明者らは硬さと打ち抜き加工時のダレ量との関係を調査して、図2の結果を得た。なお、ダレ量は、板厚5mmの熱延焼鈍板から30mmφの円盤を打ち抜き工具のクリアランスを板厚の9%、12%、15%として打ち抜いて、図3に示す打ち抜き側断面のダレXおよびダレZを測定した。測定したダレ量から、従来材を基準としたダレ量の改善率を次式により求めた。
Xの改善率(%):(X−Xo )×100/Xo
Zの改善率(%):(Z−Zo )×100/Zo
ただし、Xo およびZo は、HRB:81(従来の低炭素マルテンサイト系ステンレス鋼の硬さはHRBで78〜83) の従来材で得られたダレXおよびダレZの値
図2より、硬さがHRBで88以上になると、ダレ量は大きく改善されることがわかる。
これらのことから、Ni含有量を0.5 %超として、熱延焼鈍板の硬さをHRBで88以上とすることにより、打ち抜き加工時のダレ量を改善することができる。一方、HRBで100を超えると、打ち抜き加工時の金型の摩耗が早くなったり、素材の伸びが低くなってプレス成形性の低下が懸念される。Ni含有量が多すぎると熱延焼鈍板の硬さがHRBで100を超える可能性があるので、Ni含有量の上限は1.50%とする。
【0013】
上述した以外の成分は、Feと不可避的に含有されるものとする。なお、本発明においては不可避的に含有される不純物のうち、P量は、耐食性と加工性劣化防止の観点から、0.035 %以下に抑制することが望ましい。S量は、耐食性劣化防止の観点から、0.020 %以下に抑制することが望ましい。またO量は、靱性および耐食性に対して有害であるので、0.010 %以下に抑制することが望ましい。また、希土類元素を硫化物の形態制御による耐食性の向上の目的で添加することも可能である。
【0014】
本発明によるマルテンサイト系ステンレス鋼は、成分調整した溶鋼を、転炉または電気炉等の溶製炉にて溶製したのち、真空脱ガス法(RH法)、VOD法、AOD法等の公知の精錬方法で精錬し、ついで連続鋳造法あるいは造塊法でスラブ等に鋳造して、鋼素材とするのが好適である。
【0015】
【実施例】
表1に示す成分の鋼を溶製し、連続鋳造法により、厚さ200mm のスラブとし、1150℃に加熱したのち、熱間圧延して板厚5mmの熱延鋼板に仕上げ、800 ℃で焼鈍した。これより、焼き入れ前のロックウェル硬度(HRB)測定のための試験片(厚さ:5mm、幅:50mm、長さ:50mm)を採取した。また、焼き入れ前の打ち抜き加工性(打ち抜き時のダレ)を調べるための試験片も採取した。さらに、焼き入れ後のロックウェル硬度(HRC)測定のための試験片(厚さ:5mm、幅:50mm、長さ:50mm)を採取した。
【0016】
【表1】
【0017】
打ち抜き加工性の試験は熱延鋼板から150 mmφ、50mmφの円板を打ち抜き、側面から撮影した写真から、図3に示すダレ量X,Zを測定した。なお、打ち抜きに際してはクリアランスを板厚の15%とした。
また、焼き入れ前のロックウェル硬度(HRB)、焼き入れ後のロックウェル硬度(HRC)をJIS Z2245に準拠して測定した。焼入れは 900〜1050℃の温度で行った。
【0018】
試験の結果を表2に示す。
これらの表から、発明鋼はいずれも、焼入れすることにより、従来鋼である鋼No. 1と同等の安定したロックウエル硬度を示し、また、従来鋼と同様、安定したロックウエル硬度を得るための焼入れ温度範囲も広い。そして、発明鋼は、いずれもダレが少なく極めて良好な打ち抜き加工性を有していることがわかる。
【0019】
【表2】
【0020】
【発明の効果】
以上説明したように、本発明によれば、所定の焼入れ硬度を安定して得られることに加えて、焼き入れ前における、打ち抜き加工性が改善されたマルテンサイト系ステンレス鋼を提供することが可能になる。したがって、加工における製品歩留りの向上、生産性の向上、製品コストの低減などに大きく寄与することが期待できる。
【図面の簡単な説明】
【図1】Ni含有量と焼き入れ前のロックウェル硬度(HRB)との関係を示すグラフである。
【図2】低炭素マルテンサイト系ステンレス鋼の焼き入れ前のロックウェル硬度(HRB)とダレ量の従来鋼に対する改善率との関係を示すグラフである。
【図3】打ち抜き加工した鋼板の側断面を模式的に示す図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to martensitic stainless steel which is suitable for use in a vehicle member such as a disc brake material of a motorcycle or a mechanical member, and used as-quenched, in addition to necessary quenching hardness, and particularly excellent before quenching. We propose martensitic stainless steel with punchability. In the present invention,% means mass% unless otherwise specified.
[0002]
[Prior art]
The disc brake material for a motorcycle needs to have wear resistance in order to maintain the performance as a brake for a long time. This wear resistance generally improves as the hardness increases, while toughness decreases conversely. In consideration of both wear resistance and toughness, the Rockwell hardness HRC is often controlled in the range of 30 to 40.
Conventionally, high C martensitic stainless steel such as C; 0.2% SUS420J1 and C; 0.3% SUS420J2 or low C high Mn martensitic stainless steel has been used as the stainless steel used in this application. It was.
[0003]
However, the high C martensitic stainless steels such as SUS420J1 and SUS420J2 have a large variation in hardness when the quenching temperature varies. Therefore, in order to obtain a predetermined hardness only by quenching, extremely accurate heat treatment management is required. Met. Even if the quenching conditions can be controlled by tempering, there is a problem that a low Cr concentration region is formed around the Cr carbonitride precipitated by tempering, and the corrosion resistance is lowered.
[0004]
On the other hand, in the low C high Mn martensitic stainless steel as shown in Japanese Examined Patent Publication No. 60-2380, since the fluctuation of hardness with respect to the quenching temperature is alleviated, the severe heat treatment conditions as in the high C martensitic stainless steel are achieved. No management is required.
However, when manufacturing a member such as a disc brake using this material, after annealing, pickling, in the punching process before quenching, the vicinity sheared by the punching die is dragged into the plastic deformation region, The problem of “sagging (also referred to as sagging or warping)” (see FIG. 3) is likely to occur, and the problem of lowering the processing accuracy remains. If sagging occurs at the edge of the punched part, it will be necessary to maintain the outer shape and prevent chatter when sliding with other members. This has to be done extra, resulting in an increase in man-hour load and a loss in yield.
[0005]
[Problems to be solved by the invention]
As described above, the conventional low C high Mn martensitic stainless steel has the advantage that the heat treatment control is easy because the quenching hardness is less dependent on the quenching temperature. There has been a problem that sagging occurs particularly in the punching process at the molding stage.
Accordingly, the present invention provides a martensitic stainless steel that solves such problems of the prior art and that can stably obtain a predetermined quenching hardness and is excellent in punching workability before quenching. There is.
[0006]
[Means for Solving the Problems]
The gist of the present invention is as follows.
(1) By mass%, C + N: more than 0.04 to 0.10%,
Si: 0.5% or less,
Mn: 1.0-2.5%
Cr: Over 10.0-14.5%,
Cu: 0.5% or less,
Ni: more than 0.5% to 1.50%
A martensitic stainless steel excellent in punching process, characterized in that it contains Fe and the balance is Fe and inevitable impurities.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the reason which limited the component composition of the martensitic stainless steel of this invention to the said range is demonstrated.
C + N; more than 0.04 to 0.10%
C and N are both effective elements for increasing the hardness and improving the wear resistance. In the Mn amount range of the present invention, the amount of (C + N) for setting the hardness upon quenching to 30 to 40 HRC is as follows: It is in the range of more than 0.04% and less than 0.10%.
[0008]
Si: 0.5% or less
Si is an element that generates ferrite at a high temperature. If it exceeds 0.5%, it not only lowers the quenching hardness but also adversely affects toughness, so the upper limit is made 0.50%. The smaller the amount of Si, the better.
[0009]
Mn; 1.0-2.5%
Mn is an element effective for suppressing the formation of δ-ferrite at a high temperature. If the content is less than 1.0%, δ-ferrite is formed, and a quenching hardness of 30 to 40 HRC cannot be obtained. In addition, when it is going to achieve the quenching hardness of 30-40HRC with a high (C + N) component system, since the range of appropriate (C + N) amount becomes remarkably narrow, manufacturability falls.
If the amount of Mn is too low, the temperature range of the quenching heat treatment for obtaining a quenching hardness of 30 to 40 HRC becomes extremely narrow, so that the temperature control becomes difficult, so the lower limit is made 1.0%. On the other hand, if the amount of Mn exceeds 2.5%, the oxidation resistance at high temperatures decreases, the amount of scale generation in the steel plate manufacturing process increases, and the surface of the plate becomes rough, which significantly reduces the dimensional accuracy of the steel plate. Limit the upper limit to 2.5%. In order to obtain a stable quenching hardness, it is desirable to contain Mn in a range of 1.2 to 2.5%.
[0010]
Cr: Over 10.0 to 14.5%
In order to maintain the corrosion resistance, Cr must have a content of more than 10.0%. However, if it exceeds 14.5%, even if the upper limit amounts of Mn, Ni and Cu are added, δ-ferrite appears in the quenching temperature range of 850 to 1050 ° C, and a quenching hardness of 30 to 40 HRC is obtained. It becomes impossible. Therefore, the Cr content is in the range of more than 10.0 to 14.5%.
[0011]
Cu: 0.5% or less
Cu, like Mn, is effective in preventing the formation of δ ferrite at high temperatures. In the present invention, the object can be achieved by adding Mn in an amount of 1.0 to 2.5%, but it can be added as necessary. At that time, if excessively added, surface flaws are generated during hot rolling at a high temperature, and the yield is lowered. Therefore, it is contained in a range of 0.5% or less.
[0012]
Ni: more than 0.5% to 1.50%
Ni is an important element in the present invention, and needs to be contained in the range of more than 0.5% to 1.50%.
In low-carbon martensitic stainless steel (base components: 0.05% C, 0.3% Si, 1.5% Mn, 12.5% Cr, 0.1% Cu, 0.01% N), Ni content and Rockwell hardness of hot-rolled annealed plate When the relationship with (HRB) was examined, the result of FIG. 1 was obtained. FIG. 1 shows that the hardness increases with the Ni content when the Ni content is in the range of more than 0.5% to 1.50%.
Next, the inventors investigated the relationship between hardness and the amount of sag during punching, and obtained the results shown in FIG. The amount of sag is determined by punching a 30 mmφ disc from a hot-rolled annealed plate having a thickness of 5 mm and punching the clearance of the tool as 9%, 12%, and 15% of the plate thickness. Sagging Z was measured. From the measured amount of sag, the improvement rate of the amount of sag based on the conventional material was obtained by the following equation.
X improvement rate (%): (X-Xo) × 100 / Xo
Z improvement rate (%): (Z-Zo) × 100 / Zo
However, Xo and Zo are values of sagging X and sagging Z obtained with the conventional material of HRB: 81 (the hardness of conventional low carbon martensitic stainless steel is 78 to 83 in HRB). It can be seen that when the HRB is 88 or more, the sagging amount is greatly improved.
For these reasons, the amount of sag during punching can be improved by setting the Ni content to more than 0.5% and the hardness of the hot-rolled annealing plate to be 88 or more in HRB. On the other hand, when the HRB exceeds 100, there is a concern that wear of the mold at the time of the punching process is accelerated, or that the elongation of the material is lowered and the press formability is lowered. If the Ni content is too large, the hardness of the hot-rolled annealed plate may exceed 100 in HRB, so the upper limit of the Ni content is 1.50%.
[0013]
Components other than those described above are inevitably contained with Fe. In the present invention, among impurities inevitably contained, the amount of P is desirably suppressed to 0.035% or less from the viewpoint of corrosion resistance and workability deterioration prevention. The amount of S is desirably suppressed to 0.020% or less from the viewpoint of preventing corrosion resistance deterioration. Moreover, since the amount of O is harmful to toughness and corrosion resistance, it is desirable to suppress it to 0.010% or less. It is also possible to add rare earth elements for the purpose of improving corrosion resistance by controlling the form of sulfides.
[0014]
The martensitic stainless steel according to the present invention is prepared by melting a component-adjusted molten steel in a melting furnace such as a converter or an electric furnace, and then known vacuum degassing method (RH method), VOD method, AOD method, etc. It is preferable that the steel material is made by refining by the refining method, and then cast into a slab or the like by the continuous casting method or the ingot-making method.
[0015]
【Example】
Steels with the components shown in Table 1 are melted and made into slabs with a thickness of 200 mm by continuous casting, heated to 1150 ° C, hot rolled to a hot rolled steel plate with a thickness of 5 mm, and annealed at 800 ° C. did. From this, specimens (thickness: 5 mm, width: 50 mm, length: 50 mm) for measuring Rockwell hardness (HRB) before quenching were collected. In addition, a test piece for examining the punching workability (sag during punching) before quenching was also collected. Further, test pieces (thickness: 5 mm, width: 50 mm, length: 50 mm) for measuring Rockwell hardness (HRC) after quenching were collected.
[0016]
[Table 1]
[0017]
For the punching workability test, 150 mmφ and 50 mmφ discs were punched from a hot-rolled steel plate, and sagging amounts X and Z shown in FIG. 3 were measured from a photograph taken from the side. In the punching, the clearance was 15% of the plate thickness.
Further, the Rockwell hardness (HRB) before quenching and the Rockwell hardness (HRC) after quenching were measured according to JIS Z2245. Quenching was performed at a temperature of 900-1050 ° C.
[0018]
The test results are shown in Table 2.
From these tables, all of the inventive steels show a stable Rockwell hardness equivalent to that of Steel No. 1 which is a conventional steel by quenching, and, as with the conventional steel, quenching to obtain a stable Rockwell hardness. Wide temperature range. It can be seen that all the inventive steels have very good punching workability with little sagging.
[0019]
[Table 2]
[0020]
【The invention's effect】
As described above, according to the present invention, it is possible to provide martensitic stainless steel with improved punchability before quenching, in addition to stably obtaining a predetermined quenching hardness. become. Therefore, it can be expected to greatly contribute to improvement of product yield, improvement of productivity, reduction of product cost, and the like in processing.
[Brief description of the drawings]
FIG. 1 is a graph showing the relationship between Ni content and Rockwell hardness (HRB) before quenching.
FIG. 2 is a graph showing the relationship between Rockwell hardness (HRB) before quenching of low carbon martensitic stainless steel and improvement rate of sagging amount with respect to conventional steel.
FIG. 3 is a diagram schematically showing a side cross-section of a stamped steel sheet.
Claims (1)
C+N:0.04超〜0.10%、
Si:0.5 %以下、
Mn:1.0 〜2.5 %、
Cr:10.0超〜14.5%、
Cu:0.5 %以下、
Ni:0.5 %超〜1.50%
を含有し、残部はFeおよび不可避的不純物から成ることを特徴とする打ち抜き加工性に優れたマルテンサイト系ステンレス鋼。% By mass
C + N: more than 0.04 to 0.10%,
Si: 0.5% or less,
Mn: 1.0-2.5%
Cr: Over 10.0-14.5%,
Cu: 0.5% or less,
Ni: more than 0.5% to 1.50%
A martensitic stainless steel excellent in punching process, characterized in that it contains Fe and the balance is Fe and inevitable impurities.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2001090821A JP4496659B2 (en) | 2001-03-27 | 2001-03-27 | Martensitic stainless steel with excellent punchability |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2001090821A JP4496659B2 (en) | 2001-03-27 | 2001-03-27 | Martensitic stainless steel with excellent punchability |
Publications (2)
Publication Number | Publication Date |
---|---|
JP2002285294A JP2002285294A (en) | 2002-10-03 |
JP4496659B2 true JP4496659B2 (en) | 2010-07-07 |
Family
ID=18945553
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2001090821A Expired - Lifetime JP4496659B2 (en) | 2001-03-27 | 2001-03-27 | Martensitic stainless steel with excellent punchability |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP4496659B2 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106906429B (en) * | 2017-03-01 | 2018-10-30 | 西安交通大学 | A kind of superhigh intensity martensitic stain less steel and preparation method thereof |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002121656A (en) * | 2000-10-18 | 2002-04-26 | Sumitomo Metal Ind Ltd | Stainless steel for disk brake rotor |
JP2002146488A (en) * | 2000-08-31 | 2002-05-22 | Kawasaki Steel Corp | Martensitic stainless steel having excellent workability |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6179751A (en) * | 1984-09-27 | 1986-04-23 | Nippon Stainless Steel Co Ltd | Low-carbon martensitic stainless steel |
JPH02111846A (en) * | 1988-10-19 | 1990-04-24 | Kawasaki Steel Corp | Martensitic stainless steel excellent in press formability |
JPH10259458A (en) * | 1997-03-18 | 1998-09-29 | Nisshin Steel Co Ltd | Martensitic stainless steel sheet little sag at blanking and its production |
JPH11302795A (en) * | 1998-04-17 | 1999-11-02 | Nippon Steel Corp | Stainless steel for building construction |
-
2001
- 2001-03-27 JP JP2001090821A patent/JP4496659B2/en not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2002146488A (en) * | 2000-08-31 | 2002-05-22 | Kawasaki Steel Corp | Martensitic stainless steel having excellent workability |
JP2002121656A (en) * | 2000-10-18 | 2002-04-26 | Sumitomo Metal Ind Ltd | Stainless steel for disk brake rotor |
Also Published As
Publication number | Publication date |
---|---|
JP2002285294A (en) | 2002-10-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
KR100765661B1 (en) | Low carbon martensitic stainless steel and production method thereof | |
EP2439304B1 (en) | Steel sheet for brake disc, and brake disc | |
TWI404808B (en) | Boron steel sheet with high quenching property and manufacturing method thereof | |
US9194017B2 (en) | Hot-rolled steel sheet having excellent cold formability and hardenability and method for manufacturing the same | |
JP2004360003A (en) | Ferritic stainless steel sheet superior in press formability and fabrication quality, and manufacturing method therefor | |
WO2009131248A1 (en) | Low-carbon martensitic cr-containing steel | |
JPH10273756A (en) | Cold tool made of casting, and its production | |
JP2015081367A (en) | Hot rolled steel sheet excellent in drawability and surface hardness after carburization heat treatment | |
JP6615255B2 (en) | Disc brake rotor for automobile | |
JPS6059053A (en) | Hot working tool steel | |
JP4496908B2 (en) | Brake disc excellent in tempering softening resistance and manufacturing method thereof | |
JP2012172211A (en) | METHOD OF MANUFACTURING LOW Ni AUSTENITIC STAINLESS STEEL SHEET | |
JP2007247027A (en) | HIGH HEAT RESISTANT Cr-CONTAINING STEEL FOR BRAKE DISC | |
JP4272394B2 (en) | Ferritic stainless steel with excellent precision punchability | |
JP5351528B2 (en) | Cold mold steel and molds | |
JP4655437B2 (en) | Martensitic stainless steel with excellent workability | |
JP2019173087A (en) | Martensitic stainless hot rolled steel sheet, manufacturing method of disc brake rotor using the steel sheet | |
JP2002146482A (en) | Steel sheet for disk brake having improved warpage resistance and disk | |
JP4830239B2 (en) | Manufacturing method of low carbon martensitic stainless hot rolled steel sheet with excellent punchability | |
JP4471486B2 (en) | Medium and high carbon steel plates with excellent deep drawability | |
JP2001271143A (en) | Ferritic stainless steel excellent in ridging resistance and its production method | |
JPH03254342A (en) | Manufacture of raw material for bearing having excellent service life to rolling fatigue | |
JP4496659B2 (en) | Martensitic stainless steel with excellent punchability | |
JP3371952B2 (en) | Manufacturing method of soft high carbon steel sheet for processing that can omit pickling process | |
JP4577936B2 (en) | Method for producing martensitic stainless steel with excellent strength, ductility and toughness |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20071225 |
|
A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20100311 |
|
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: 20100323 |
|
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: 20100405 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130423 Year of fee payment: 3 |
|
R150 | Certificate of patent or registration of utility model |
Ref document number: 4496659 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130423 Year of fee payment: 3 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140423 Year of fee payment: 4 |
|
EXPY | Cancellation because of completion of term |