JPS6320142A - Cast steel slab having excellent hydrogen inducing crack resistance - Google Patents
Cast steel slab having excellent hydrogen inducing crack resistanceInfo
- Publication number
- JPS6320142A JPS6320142A JP61161916A JP16191686A JPS6320142A JP S6320142 A JPS6320142 A JP S6320142A JP 61161916 A JP61161916 A JP 61161916A JP 16191686 A JP16191686 A JP 16191686A JP S6320142 A JPS6320142 A JP S6320142A
- Authority
- JP
- Japan
- Prior art keywords
- slab
- occupied area
- continuous casting
- amn
- treatment
- 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.)
- Granted
Links
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims abstract description 11
- 229910052739 hydrogen Inorganic materials 0.000 title claims abstract description 11
- 239000001257 hydrogen Substances 0.000 title claims abstract description 11
- 230000001939 inductive effect Effects 0.000 title abstract 3
- 229910001208 Crucible steel Inorganic materials 0.000 title 1
- 238000009792 diffusion process Methods 0.000 claims abstract description 9
- 238000005266 casting Methods 0.000 claims abstract description 5
- 238000002791 soaking Methods 0.000 claims abstract description 5
- 238000005336 cracking Methods 0.000 claims description 14
- 229910000831 Steel Inorganic materials 0.000 abstract description 14
- 239000010959 steel Substances 0.000 abstract description 14
- 238000009749 continuous casting Methods 0.000 abstract description 6
- 238000010438 heat treatment Methods 0.000 abstract description 6
- 239000000203 mixture Substances 0.000 abstract description 6
- 238000005096 rolling process Methods 0.000 abstract description 5
- 238000005204 segregation Methods 0.000 description 15
- 238000007711 solidification Methods 0.000 description 8
- 230000008023 solidification Effects 0.000 description 8
- 238000000034 method Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 3
- 238000011156 evaluation Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
- 150000003463 sulfur Chemical class 0.000 description 1
Landscapes
- Analysing Materials By The Use Of Radiation (AREA)
- Metal Rolling (AREA)
- Continuous Casting (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、油井管その他に用いられる耐水素誘起割れ性
に優れた鋼鋳片に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a steel slab with excellent resistance to hydrogen-induced cracking used for oil country tubular goods and other products.
（従来の技術）
従来の連続鋳造鋳片（以下連鋳ｖｊ片という）の品質評
価の仕方としては、サルファープリント法、マクロエッ
チ法等があり、一般的には、前者の方が利用されている
。(Prior art) Conventional methods for evaluating the quality of continuously cast slabs (hereinafter referred to as continuous cast slabs) include the sulfur print method and the macro etch method, but the former is generally used. There is.
このサルファープリント法では、鋳片の特に中心部近傍
の偏析状態が簡便に評価できるため、品種別の判定基準
として連続鋳造では広く利用されてきた。特に−殻構造
物、造船材等の鋼板を製造する場合、この方法はきわめ
て優れた方法であった。This sulfur print method allows easy evaluation of the segregation state of slabs, especially near the center, and has been widely used in continuous casting as a criterion for determining product types. In particular, this method was an extremely excellent method when manufacturing steel plates for shell structures, shipbuilding materials, etc.
しかしながら次のような場合には有効な手段とならない
のが現状であった。水素誘起割れの原因としては、Ｓ以
外の元素であるＰ、Ｍｎ 等の凝固最終部近傍で起こ
る偏析と、鋼板の割れとの関係が極めて強く、従来のサ
ルファープリント法、マクロエッチ法での評定では、不
正確である。However, the current situation is that it is not an effective means in the following cases. The cause of hydrogen-induced cracking is that there is a strong relationship between segregation of elements other than S, such as P and Mn, near the final stage of solidification, and cracking of the steel plate. That's inaccurate.
そのだめ現状では、上記のような割れが問題となる鋼種
の製造については、鋳片段階で均熱拡散処理または、ブ
レイクダウン均熱拡散処理あるいは、高温加熱拡散処理
等を実施し、全ての元素の拡散処理後圧延する方法がと
られてきた。Therefore, at present, when manufacturing steel types that are prone to cracking as described above, soaking diffusion treatment, breakdown soaking diffusion treatment, high-temperature heating diffusion treatment, etc. are carried out at the slab stage to ensure that all elements are removed. A method of rolling after diffusion treatment has been adopted.
（発明が解決し」：うとする問題点）
」１記のような水素誘起割れと偏析量との関係は明らか
にされておらず、成分調整、ロールピッチの短縮化、凝
固組織の等軸晶化を実施しているが、必ずしも目的の鋳
片を得るに至っていない。(Problems to be Solved by the Invention) The relationship between hydrogen-induced cracking and the amount of segregation as described in item 1 has not been clarified. However, the desired slabs have not necessarily been obtained.
本発明者らは鋳片におけるＰ、Ｍｎの偏析状態と割れ特
性の関係を調査した結果、Ｐ＞０．０４％、Ｍｎ ＞
１−、５ ％の濃度以上の面積率と、 割れ特性に密接
な関係があることを知った。The present inventors investigated the relationship between the segregation state of P and Mn in slabs and cracking characteristics, and found that P > 0.04%, Mn >
I learned that there is a close relationship between the area ratio with a concentration of 1-5% or higher and the cracking characteristics.
即ち本発明は、耐水素誘起割れ特性に優れた均熱拡散熱
処理省略型の連続鋳造鋳片を提供するものである。That is, the present invention provides a continuously cast slab that has excellent hydrogen-induced cracking resistance and does not require soaking diffusion heat treatment.
（問題点を解決するだめの手段）
本発明者らは、後記した溶鋼成分の連鋳鋳片を、新たな
偏析評価方法にもとすき評価し、これらを圧延して成品
としたものの水素誘起割れ特性を調査した。その結果第
１図に示すように、ＰとＭｎの偏析と成品の割れ特性と
の間に、一定の関係を見いたした。(Another means to solve the problem) The present inventors evaluated continuous cast slabs of the molten steel composition described below using a new segregation evaluation method, and the hydrogen-induced The cracking characteristics were investigated. As a result, as shown in FIG. 1, a certain relationship was found between the segregation of P and Mn and the cracking characteristics of the product.
図中○印は割れなし、Ｘ印は割れありを示した。In the figure, ○ marks indicate no cracks, and X marks indicate cracks.
すなわち、Ｐの偏析状態とＭｎの偏析状態によつて、（
コ）式により決定され、ＡＰを（］）式で満たされる範
囲に制御することにより、水素誘起割れが発生しないこ
とを見い出した。That is, depending on the segregation state of P and the segregation state of Mn, (
It has been found that hydrogen-induced cracking does not occur by controlling AP within a range that is determined by equation () and is satisfied by equation (]).
ｌｏｇ（ＡＰ）≦−０，４χＩｏｇ（ＡＭｎ） −１．
］２ ・・−・−（］、）ここにいう占有面積率Ａ、Ｐ
、ＡＭｎとは、連鋳鋳片の鋳造方向の断面における厚み
方向の最終凝固部、および■偏析部を含む４０Ｘ２０ｍ
＋ｎの試片内におけるＰ）０．０４％の面積の占める比
率およびＭｎ＞１．５％の面積の占める比率を示す。log(AP)≦−0, 4χIog(AMn) −1.
]2 ・・−・−(],)The occupied area ratio A, P here
, AMn is 40 x 20 m including the final solidified part in the thickness direction and the segregated part in the cross section of the continuously cast slab in the casting direction.
The ratio of the area occupied by P) 0.04% and the ratio occupied by the area of Mn>1.5% in the +n specimen are shown.
ところで本発明におけるＰ、Ｍｎ の偏析面積率の算
定は、特に限定されないが、だとえは特開昭５７− ］
、 ４２５５１号公報によるマイクロアナライザー処理
で行なうのが便利である。By the way, the calculation of the segregation area ratio of P and Mn in the present invention is not particularly limited, but it is disclosed in Japanese Patent Application Laid-Open No. 1983-1992.
It is convenient to carry out the microanalyzer processing according to Japanese Patent Publication No. 42551.
（作用）
第１図からＭｎ偏析部の面積が小さくなれば、Ｐ偏析部
の面積は多少大きくなってもよいととがわかる。(Function) It can be seen from FIG. 1 that if the area of the Mn segregation part becomes smaller, the area of the P segregation part may become somewhat larger.
本発明によると、連鋳鋳片の中心部（最終凝固部）の試
片（４０χ２０論）を取りだし、この部分を例えば、特
開昭５７−１４２５５１号による５〇μｍ ビーム径の
マイクロアナライザーで全面分析し、試片内のＰ ＋
Ｍｎ の偏析濃度別の占有面積率をもって、Ｐ 、
Ｍｎの偏析状況を評価することが望ましい。また、Ｐの
測定誤差を加味し、１０チ以内の誤差にするため、Ｘ線
照射時間を、１００ｍ５ｅｃ 以上にすることが望ま
しい。According to the present invention, a specimen (40x20 theory) of the central part (final solidification part) of a continuously cast slab is taken out, and this part is analyzed over the entire surface with a microanalyzer with a beam diameter of 50 μm according to Japanese Patent Application Laid-Open No. 57-142551. Analyze and P + in the specimen
With the occupied area ratio for each segregation concentration of Mn, P,
It is desirable to evaluate the segregation status of Mn. Furthermore, in order to take into account the measurement error of P and keep the error within 10 inches, it is desirable to set the X-ray irradiation time to 100 m5ec or more.
即ち第２図に示すように、連鋳鋳片］０の長手方向（以
下り方向という）の断面は、通常厚み方向の最終凝固位
置１１が線状を呈しておシ、従って最終凝固部を含む所
望面積１２を試料とする。That is, as shown in Fig. 2, the cross section in the longitudinal direction (hereinafter referred to as the "downward direction") of the continuously cast slab 0 shows that the final solidification position 11 in the thickness direction usually has a linear shape. A desired area 12 containing the sample is taken as a sample.
試片１２は、連鋳鋳片のＬ方向断面積の４０Ｘ２０゜以
上の面積をもつものとするが、好壕しくは第３図に示す
ように、中心偏析と■偏析を共通にもつ視野にすると効
率的で好ましい。The specimen 12 shall have an area of 40 x 20° or more of the cross-sectional area in the L direction of the continuously cast slab, but it is preferable to have a trench in a field of view that has central segregation and segregation in common, as shown in Figure 3. This is efficient and preferable.
第４図は取鍋ｐ＝＝Ｑ、ＱＱ５係で鋳造された鋳片の測
定例であるが、４０Ｘ２０−の試片を６倍に拡大したも
のである。図中で黒色のマーキングＡは、Ｐ＝Ｏ，０１
％の等濃度域、斜線のマーキングＢは、Ｐ＝０．０２チ
の等濃度域、マーキングＣは、Ｐ−０，０４係の等偏析
Ｐ濃度域である。Fig. 4 shows a measurement example of a slab cast using a ladle p==Q, QQ5, and the 40x20- specimen is enlarged six times. In the figure, black marking A is P=O,01
%, the diagonal marking B is an equal concentration region of P=0.02, and the marking C is an equal concentration P concentration region of P-0.04.
即ちこのケースでは、４０χ２０調試片全面積中で、偏
析Ｐ濃度が０．０４チ以上の面積率は、０．００２係、
０．０２チ以上の面積率は０．２７係、０．０１％以上
の面積率は５．６７％の例を示している。That is, in this case, the area ratio of the segregated P concentration of 0.04 or more in the total area of the 40x20 sample is 0.002
An example is shown in which the area ratio of 0.02 inches or more is 0.27%, and the area ratio of 0.01% or more is 5.67%.
第１図の供試鋼の溶鋼成分は、主としてＣ０，５係以下
、 Ｓｉ ０．０１−１．０％、 Ｍｎ ０．７−１
．５ ’＄。The molten steel composition of the test steel shown in Figure 1 is mainly C0.5 or less, Si 0.01-1.0%, Mn 0.7-1
．． 5'$.
Ｐｏ、０２係以下、Ｓｏ、Ｏ０５チ以下、００．００４
チを基本成分とし、さらに基本成分に必要に応じてＣａ
マＯｐｐｍ以下、 ＲｇＭ ０．０４％以下、 Ｎｂ
Ｏ，０１−０，５％、 ＶＯ，Ｏｌ−ｏ、５％、 Ｃｕ
、 １％以下、 Ｃｒ１％以下１Ｍ０１％以下、 Ｚ
ｒ ０．０１−０．５％。Po, 02 and below, So, 05 and below, 00.004
Ca is the basic component, and Ca is added to the basic component as necessary.
M Oppm or less, RgM 0.04% or less, Nb
O,01-0,5%, VO,Ol-o,5%, Cu
, 1% or less, Cr1% or less, 1M01% or less, Z
r 0.01-0.5%.
Ｎｉ ｌ係以下、ＴｉＯ，Ｏ１〜０．３％等の１種以上
を適宜含んだものである。It appropriately contains at least one of Ni, TiO, and 1 to 0.3% of O.
Ｍｎは、材料に要求される強度を確保するため、０．７
係乃至１．５％添加されるが、１．５係以上は、著しく
割れ感受性を強めるだめ、Ｐとの相関により制限される
。Mn is 0.7 to ensure the strength required for the material.
It is added in an amount of 1.5% to 1.5%, but if it exceeds 1.5%, the cracking susceptibility is significantly increased, so it is limited due to the correlation with P.
ところで、前述して来た様なＰ＞０．０４係、Ｍｎ ）
１．５ ％ 以上の占有面積率に影響を与える因子は
、溶鋼成分では当然取鍋ｐ％、Ｍｎ係であシ、次にその
溶鋼が固まる時の凝固条件（タンディシュ加熱度ΔＴ、
ロールピッチ］−ｐ、 最終凝固部での溶鋼静圧Ｐ、鋳
片表面温度℃、シェル厚み）である。By the way, as mentioned above, P > 0.04, Mn)
Factors that affect the occupied area ratio of 1.5% or more are of course the ladle p% and Mn ratio in the molten steel composition, and the solidification conditions when the molten steel solidifies (tundish heating degree ΔT,
roll pitch]-p, molten steel static pressure P at the final solidification part, slab surface temperature °C, shell thickness).
従って上述のＰ、Ｍｎ占有面積率を考慮して、前記連続
鋳造条件と溶鋼成分を選択することにより、本発明の鋳
片は製造される。特にロールピッチや最終凝固部での溶
鋼静圧等は、Ｐ、Ｍｎの占有面積率を小さくするために
重要であり、そのため特願昭６０− ］、 ’？ ］、
３１．４号による稠密ロールや、特願昭６０−２３０
０９１号によるウオーキングバーによる最適な凝固末期
圧下が有効である。Therefore, the slab of the present invention is manufactured by selecting the continuous casting conditions and molten steel composition in consideration of the above-mentioned P and Mn occupied area ratios. In particular, the roll pitch and the static pressure of molten steel in the final solidification zone are important in order to reduce the occupied area ratio of P and Mn. ],
Dense roll according to No. 31.4, patent application 1986-230
Optimal final solidification reduction using a walking bar according to No. 091 is effective.
（実施例）
Ｃ＝０．０７５％、Ｍｎ ＝ １．０３ ％、Ｓｉ ＝
０．２５６φ、Ｐ、：０．００２９係、Ｓ＝Ｏ，０Ｏ
１５係、ｖ＝０．３１％、 Ｎｂ＝ｏ、ｏ ４１１％、
Ｃａ／５＝＝１．５３の溶鋼を、１０５Ｒ連鋳機にて
、最終凝固部近傍をウオーキングバーで面支持しながら
鋳造した。(Example) C=0.075%, Mn=1.03%, Si=
0.256φ, P: 0.0029 ratio, S=O, 0O
Section 15, v=0.31%, Nb=o, o 411%,
Molten steel with Ca/5==1.53 was cast in a 105R continuous caster while supporting the surface near the final solidification part with a walking bar.
その中心部近傍より４０Ｘ２０．の試片を取り出し、前
記→イクロアナライザー処理をほどこし、Ｐ）Ｏ○４係
、 Ｍｎ ：） １． ］５ チの占有面積率を求めた
所、それぞれｏ、 ０５ ％、０３％であったので、拡
散熱処理を施すことなく、その！、ま圧延工程に送り、
圧延後Ｎ Ａ、 ＣＥ 基準による水素誘起割れテス
）ｋ実施した所、全て合格であった。40X20 from near the center. Take out the specimen and apply the → microanalyzer treatment as described above, P)O○4 Section, Mn:) 1. ] 5 The occupied area ratios of 0 and 05% and 03% were calculated, respectively, so without performing diffusion heat treatment, that! , then sent to the rolling process.
After rolling, hydrogen-induced cracking tests were conducted according to NA and CE standards, and all tests passed.
第１図はＡＰ−ＡＭｎ 相関関係のグラフ、第２図は本
発明の試片採取の説明図、第３図は評価のだめの測定視
野の説明図、第４図（、）はＰ占有面積率算定のだめの
マイクロアナライザーによる解析図、第４図（ｂ）は第
４図（ａ）の部分拡大図である。
代理人 弁理士 茶野木 立 夫
第４図（ｃｌ）
ρ
、ｙ”、Ｑ
る−
べ２
・ ９・９ 第４図（ｂ）
°、り３
、／
Ｃ
ν １８
゛ −づ゛
−〃 、 Ａ
；斐すオこイ見野Fig. 1 is a graph of AP-AMn correlation, Fig. 2 is an explanatory diagram of specimen collection of the present invention, Fig. 3 is an explanatory diagram of the measurement field of view for evaluation, and Fig. 4 (, ) is the P occupied area ratio. Fig. 4(b) is a partially enlarged view of Fig. 4(a), which is a diagram analyzed by the microanalyzer of the calculation. Agent Patent Attorney Tatsuo Chanoki Figure 4 (cl) ρ, y”, Q Ru-be2・9・9 Figure 4 (b) °, Ri3, / C ν 18゛-zu゛-〃, A ; Hisu Okoi Mino
Claims (1)
方向の断面をとり、且つ厚み方向の最終凝固部を含み、
前記鋳造方向の望ましくは少なくとも４０ｍｍを含み、
且つ厚み方向２０ｍｍを含む視野内で、０．０４％以上
のＰの占有面積率ＡＰをＹ軸とし、１．５％以上のＭｎ
の占有面積率ＡＭｎをＸ軸とするとき、ｌｏｇ（ＡＰ）
≦−０．４Ｘｌｏｇ（ＡＭｎ）−１．２としたことを特
徴とする耐水素誘起割れ特性に優れた均熱拡散処理省略
型連続鋳片。A cross section in the casting direction is taken at the center in the width direction of the continuously cast slab or at an appropriate position, and includes the final solidified part in the thickness direction,
preferably comprising at least 40 mm of said casting direction;
In addition, within the field of view including 20 mm in the thickness direction, the Y axis is the occupied area ratio AP of P of 0.04% or more, and Mn of 1.5% or more
When the occupied area rate AMn is taken as the X axis, log(AP)
A continuous slab that does not require soaking diffusion treatment and has excellent hydrogen-induced cracking resistance, characterized in that ≦-0.4Xlog(AMn)-1.2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61161916A JPH069733B2 (en) | 1986-07-11 | 1986-07-11 | Judgment method of steel slab excellent in hydrogen-induced cracking resistance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61161916A JPH069733B2 (en) | 1986-07-11 | 1986-07-11 | Judgment method of steel slab excellent in hydrogen-induced cracking resistance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6320142A true JPS6320142A (en) | 1988-01-27 |
| JPH069733B2 JPH069733B2 (en) | 1994-02-09 |
Family
ID=15744462
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61161916A Expired - Lifetime JPH069733B2 (en) | 1986-07-11 | 1986-07-11 | Judgment method of steel slab excellent in hydrogen-induced cracking resistance |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH069733B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009236842A (en) * | 2008-03-28 | 2009-10-15 | Jfe Steel Corp | Method for evaluating center segregation |
| JP2014172074A (en) * | 2013-03-08 | 2014-09-22 | Kobe Steel Ltd | Destination change method by qualitative determination of sour-resistant steel slab |
| JP2015058473A (en) * | 2013-09-20 | 2015-03-30 | 株式会社神戸製鋼所 | Destination change method by qualitative determination of sour resistant line pipe steel slab |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5773162A (en) * | 1980-10-27 | 1982-05-07 | Kawasaki Steel Corp | Steel products with superior hydrogen induced cracking resistance |
| JPS586961A (en) * | 1981-07-03 | 1983-01-14 | Kawasaki Steel Corp | Steel products with superior hydrogen induced cracking resistance |
| JPS60228655A (en) * | 1985-04-08 | 1985-11-13 | Kawasaki Steel Corp | Steel material having superior resistance to hydrogen induced cracking |
-
1986
- 1986-07-11 JP JP61161916A patent/JPH069733B2/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5773162A (en) * | 1980-10-27 | 1982-05-07 | Kawasaki Steel Corp | Steel products with superior hydrogen induced cracking resistance |
| JPS586961A (en) * | 1981-07-03 | 1983-01-14 | Kawasaki Steel Corp | Steel products with superior hydrogen induced cracking resistance |
| JPS60228655A (en) * | 1985-04-08 | 1985-11-13 | Kawasaki Steel Corp | Steel material having superior resistance to hydrogen induced cracking |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009236842A (en) * | 2008-03-28 | 2009-10-15 | Jfe Steel Corp | Method for evaluating center segregation |
| JP2014172074A (en) * | 2013-03-08 | 2014-09-22 | Kobe Steel Ltd | Destination change method by qualitative determination of sour-resistant steel slab |
| JP2015058473A (en) * | 2013-09-20 | 2015-03-30 | 株式会社神戸製鋼所 | Destination change method by qualitative determination of sour resistant line pipe steel slab |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH069733B2 (en) | 1994-02-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101094568B1 (en) | Casting steel strip with low surface roughness and low porosity | |
| EP3222744A1 (en) | High toughness and high tensile strenght thick steel plate with excellent material homogeneity and production method for same | |
| JP4582916B2 (en) | Method for twin-roll continuous casting of ferritic stainless steel without microcracks | |
| JP2002086252A (en) | Continous casting method | |
| JPS62256950A (en) | High-strength steel wire rod excellent in wiredrawability | |
| JPS6320142A (en) | Cast steel slab having excellent hydrogen inducing crack resistance | |
| KR950006273B1 (en) | Method for wear-resistant compound roll manufacture | |
| JP3596290B2 (en) | Steel continuous casting method | |
| KR100550291B1 (en) | Method for continuous annealing and pickling of high chrome ferritic stainless steel plate | |
| JP6862723B2 (en) | Continuously cast steel slabs and continuous casting methods | |
| JP3406459B2 (en) | Cooling method for continuous casting bloom | |
| CA1110822A (en) | Continuous casting | |
| JPS6320412A (en) | Hot working method for austenitic stainless steel containing mo and n | |
| JP3091795B2 (en) | Manufacturing method of steel bars with excellent drawability | |
| JPH11179509A (en) | Continuous casting method of billet cast slab | |
| US4408652A (en) | Method of continuously casting nickel containing steel wherein surface cracks are prevented | |
| JP3900851B2 (en) | Manufacturing method of steel sheet with excellent surface properties | |
| JPS59177352A (en) | Low-decarburization spring steel for continuous casting | |
| JP6515291B2 (en) | Continuous steel casting method | |
| JP2838467B2 (en) | Method for producing Cr-Ni stainless steel alloy free from surface flaws | |
| JPS5852444B2 (en) | Method for suppressing steel billet surface cracking during hot rolling | |
| JP2561476B2 (en) | Method for preventing cracking during rapid solidification of Cr-Ni stainless steel or Cr-Ni high alloy steel | |
| JP2004307931A (en) | Continuously cast piece, and casting method therefor | |
| JPH0251971B2 (en) | ||
| JP3494136B2 (en) | Continuous cast slab, casting method thereof, and method of manufacturing thick steel plate |