JPH0551699A - High toughness seamless steel pipe - Google Patents
High toughness seamless steel pipeInfo
- Publication number
- JPH0551699A JPH0551699A JP10237191A JP10237191A JPH0551699A JP H0551699 A JPH0551699 A JP H0551699A JP 10237191 A JP10237191 A JP 10237191A JP 10237191 A JP10237191 A JP 10237191A JP H0551699 A JPH0551699 A JP H0551699A
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- Prior art keywords
- steel pipe
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- content
- seamless steel
- steel
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- 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.)
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- Heat Treatment Of Articles (AREA)
Abstract
(57)【要約】
【構成】重量％で、Ｃ：0.15〜0.40％、Si：0.05〜0.50
％、Mn：0.50〜2.00％、Al： 0.005〜0.050 ％、Cr：1.
00〜3.00％、Mo：0.10〜1.00％、Nb： 0.005〜0.050 ％
を含有し、あるいは、さらに、Ni：1.00〜3.00％、Ｖ：
0.02〜0.10％、Ti： 0.010〜0.100 ％、Ｂ：0.0010〜0.
0050％のうちの１種以上を含有し、残部がFeおよび不純
物からなり、不純物のＳ、Ｐ、Ｏがそれぞれ 0.025％以
下、0.015 ％以下、0.0010％以下である継目無鋼管。
【効果】高い強度と優れた靱性を有し、特に、自動車の
鋼管製ドア補強材として、あるいはその他の機械構造用
部材として好適である。(57) [Summary] [Structure] C: 0.15 to 0.40% by weight, Si: 0.05 to 0.50
%, Mn: 0.50 to 2.00%, Al: 0.005 to 0.050%, Cr: 1.
00 to 3.00%, Mo: 0.10 to 1.00%, Nb: 0.005 to 0.050%
Or in addition, Ni: 1.00 to 3.00%, V:
0.02-0.10%, Ti: 0.010-0.100%, B: 0.0010-0.
A seamless steel pipe containing at least one of 50%, the balance being Fe and impurities, and the impurities S, P, and O being 0.025% or less, 0.015% or less, and 0.0010% or less, respectively. [Effect] It has high strength and excellent toughness, and is particularly suitable as a steel pipe door reinforcing material for automobiles or other mechanical structural members.
Description
【０００１】[0001]
【産業上の利用分野】本発明は、熱間圧延ままで高い強
度と優れた靱性を有し、自動車のドア補強材などに用い
るのに好適な継目無鋼管に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seamless steel pipe which has high strength and excellent toughness as hot-rolled and is suitable for use as a vehicle door reinforcing material.
【０００２】[0002]
【従来の技術】近年、自動車の軽量化の動向に対応して
鋼管製ドア補強材の開発が進んでいる。このドア補強材
は、側面衝突時の乗員の保護を目的としてドアの内部に
設置される。従来、このような用途に使用される鋼管と
しては、例えば、電縫鋼管を高周波加熱後水焼入れし、
必要に応じて 150〜250 ℃程度で焼き戻しを行った 150
kgf/mm2 級の熱処理鋼管や、熱間圧延ままの140kgf/mm2
級の継目無鋼管が用いられている。しかし、前者の電縫
鋼管では熱処理のコストが高く、後者の継目無鋼管は靱
性が低い。そのため、150kgf/mm2級の高強度を有し、さ
らに、衝突時の突発的な応力負荷（曲げ変形）に対して
も脆性的な折損が生じないような十分な靱性を有し、し
かも、製造コストが低いことが強く求められている。2. Description of the Related Art In recent years, a steel pipe door reinforcing material has been developed in response to the trend of weight reduction of automobiles. This door reinforcement is installed inside the door for the purpose of protecting an occupant in the event of a side collision. Conventionally, as a steel pipe used for such an application, for example, an electric resistance welded steel pipe is induction-heated and then water-quenched,
If necessary, tempered at 150-250 ℃ 150
kgf / mm 2 grade heat treatment steel and, in as-hot-rolled 140 kgf / mm 2
A grade of seamless steel pipe is used. However, the former ERW steel pipe has a high heat treatment cost, and the latter seamless steel pipe has a low toughness. Therefore, it has a high strength of 150 kgf / mm 2 grade, and has sufficient toughness that brittle breakage does not occur even against sudden stress load (bending deformation) at the time of collision, and moreover, There is a strong demand for low manufacturing costs.
【０００３】[0003]
【発明が解決しようとする課題】本発明は、熱間圧延ま
まで引張強さが150kgf/mm2以上の高い強度を有するとと
もに、優れた靱性を有する継目無鋼管を提供することを
目的とする。SUMMARY OF THE INVENTION It is an object of the present invention to provide a seamless steel pipe having a high tensile strength of 150 kgf / mm 2 or more as hot-rolled and excellent toughness. ..
【０００４】[0004]
【課題を解決するための手段】本発明は、主として鋼に
適量のNbを含有させ、Ｏ (酸素) 含有量を極力低く抑え
ることにより、熱間圧延ままで高強度ならびに高靱性を
有する継目無鋼管を得ることができるという知見に基づ
いてなされたもので、その要旨は下記およびの高靱
性継目無鋼管にある（以下、「％」はすべて重量％を意
味する）。DISCLOSURE OF THE INVENTION The present invention is a seamless steel having high strength and high toughness as hot rolled by mainly containing a proper amount of Nb in steel and suppressing the O (oxygen) content as low as possible. It was made based on the finding that a steel pipe can be obtained, and its gist resides in the following and high-toughness seamless steel pipes (hereinafter, "%" all mean% by weight).
【０００５】 Ｃ：0.15〜0.40％、Si：0.05〜0.50
％、Mn：0.50〜2.00％、Cr：1.00〜3.00％、Mo：0.10〜
1.00％、Al： 0.005〜0.050 ％、Nb： 0.005〜0.050 ％
を含有し、残部がFeおよび不可避不純物からなり、不純
物中のＰが 0.025％以下、Ｓが0.015 ％以下、Ｏが0.00
10％以下である高靱性継目無鋼管。C: 0.15 to 0.40%, Si: 0.05 to 0.50
%, Mn: 0.50 to 2.00%, Cr: 1.00 to 3.00%, Mo: 0.10 to
1.00%, Al: 0.005 to 0.050%, Nb: 0.005 to 0.050%
And the balance consists of Fe and inevitable impurities, P in the impurities is 0.025% or less, S is 0.015% or less, and O is 0.00
High toughness seamless steel pipe with 10% or less.
【０００６】 前記に記載の成分に加え、さらに、
Ni：1.00〜3.00％、Ｖ：0.02〜0.10％、Ti： 0.010〜0.
100 ％およびＢ：0.0010〜0.0050％のうちの１種以上を
含有し、残部がFeおよび不可避不純物からなり、不純物
中のＰが0.025 ％以下、Ｓが0.015 ％以下、Ｏが0.0010
％以下である高靱性継目無鋼管。In addition to the ingredients described above,
Ni: 1.00 to 3.00%, V: 0.02 to 0.10%, Ti: 0.010 to 0.
100% and B: 0.0010 to 0.0050% of one or more, the balance consisting of Fe and unavoidable impurities, P in the impurities is 0.025% or less, S is 0.015% or less, and O is 0.0010.
% Toughness seamless steel pipe with less than or equal to%.
【０００７】[0007]
【作用】以下に、本発明の鋼管を構成する鋼に含まれる
各成分の作用効果とそれらの含有量の限定理由について
述べる。The function and effect of each component contained in the steel constituting the steel pipe of the present invention and the reason for limiting the content thereof will be described below.
【０００８】Ｃは鋼の強度を高める元素である。しか
し、その含有量が0.15％未満では強度の確保が不十分で
あり、一方、0.40％を超えると強度が高くなり過ぎ、靱
性に乏しくなるので、その含有量は0.15〜0.40％とす
る。C is an element that enhances the strength of steel. However, if the content is less than 0.15%, the strength is insufficiently secured, while if it exceeds 0.40%, the strength becomes too high and the toughness becomes poor, so the content is made 0.15 to 0.40%.
【０００９】Siは製鋼時の脱酸剤として必要不可欠の元
素であるが、0.05％未満では十分な効果が得られず、一
方、含有量が0.50％を超えると効果が飽和するので、そ
の含有量は0.05〜0.50％とする。Si is an indispensable element as a deoxidizing agent during steel making, but if it is less than 0.05%, a sufficient effect cannot be obtained. On the other hand, if the content exceeds 0.50%, the effect is saturated. The amount is 0.05 to 0.50%.
【００１０】Mnは鋼の強度を高める元素であるが、含有
量が0.50％未満では機械構造用部材としての強度が不十
分であり、一方、2.00％を超えると強度が高くなり過ぎ
て靱性に悪影響を及ぼす。従って、Mn含有量は0.50〜2.
00％とする。Mn is an element that enhances the strength of steel, but if the content is less than 0.50%, the strength as a mechanical structural member is insufficient, while if it exceeds 2.00%, the strength becomes too high and the toughness is increased. Adversely affect. Therefore, the Mn content is 0.50-2.
00%
【００１１】CrおよびMoは鋼の強度を向上させる元素で
あるが、それらの含有量がCrについては1.00％未満、Mo
については0.10％未満ではその効果は小さい。一方、Cr
の含有量が3.00％、Moの含有量が1.00％を超えると効果
は飽和する。従って、Cr含有量は1.00〜3.00％、Mo含有
量は0.10〜1.00％とする。Cr and Mo are elements that improve the strength of steel, but their content in Cr is less than 1.00%, Mo
About 0.10%, the effect is small. On the other hand, Cr
The effect is saturated when the content of Al exceeds 3.00% and the content of Mo exceeds 1.00%. Therefore, the Cr content is 1.00 to 3.00% and the Mo content is 0.10 to 1.00%.
【００１２】Alは鋼の脱酸に用いる元素であるが、含有
量が 0.005％未満では脱酸効果は少なく、一方、 0.050
％を超えると効果が飽和する。Al is an element used for deoxidizing steel, but if the content is less than 0.005%, the deoxidizing effect is small, while 0.050
If it exceeds%, the effect will be saturated.
【００１３】Nbは微量含有させることにより鋼の強度と
靱性を向上させる効果を有するが、含有量が 0.005％未
満ではその効果は十分ではなく、一方、 0.050％を超え
ると効果が飽和するので、その含有量は 0.005〜0.050
％とする。Nb has the effect of improving the strength and toughness of steel by containing a trace amount, but if the content is less than 0.005%, the effect is not sufficient, while if it exceeds 0.050%, the effect saturates. Its content is 0.005-0.050
%.
【００１４】前記の発明の鋼は、上記の成分以外、残
部がFeと不可避の不純物からなるものである。不純物と
しては、Ｐ、Ｓ、およびＯ (酸素) の上限を抑えること
が重要である。In the steel of the above invention, in addition to the above-mentioned components, the balance is Fe and inevitable impurities. It is important to suppress the upper limits of P, S, and O (oxygen) as impurities.
【００１５】Ｐ、Ｓは鋼の熱間での加工性を向上させる
ために極力低減させることが望ましく、その上限を、Ｐ
については 0.025％、Ｓについては0.015％とする。P and S are preferably reduced as much as possible in order to improve the hot workability of steel, and the upper limit of P and S is P
Is 0.025% and S is 0.015%.
【００１６】Ｏは 150〜180kgf/mm2級の高強度材の靱性
に大きく影響する。靱性を向上させるためには、その含
有量を極力低減させる必要があり、−40〜−60℃程度の
寒冷地での使用を考慮して、その上限を0.0010％とす
る。O greatly affects the toughness of high strength materials of 150 to 180 kgf / mm 2 grade. In order to improve the toughness, it is necessary to reduce the content as much as possible, and the upper limit is set to 0.0010% in consideration of use in cold regions of about -40 to -60 ° C.
【００１７】の発明の鋼は、の発明の鋼に、さらに
Ni、Ｖ、TiおよびＢのうち１種以上をそれぞれ所定量加
えた鋼である。The steel of the invention of
It is steel to which one or more kinds of Ni, V, Ti and B are added in predetermined amounts.
【００１８】Niは鋼の強度および靱性を向上させる元素
であるが、含有量が1.00未満ではその効果は小さく、一
方、3.00％を超えると効果は飽和する。従って、Niの含
有量は1.00〜3.00％とする。Ni is an element that improves the strength and toughness of steel, but if the content is less than 1.00, its effect is small, while if it exceeds 3.00%, the effect is saturated. Therefore, the Ni content is 1.00 to 3.00%.
【００１９】Ｖは鋼の強度を向上させる元素であるが、
0.02％未満ではその効果は小さく、一方、0.10％を超え
ると靱性が劣化するので、その含有量は0.02〜0.10％と
する。V is an element that improves the strength of steel,
If it is less than 0.02%, its effect is small, while if it exceeds 0.10%, the toughness deteriorates, so its content is made 0.02 to 0.10%.
【００２０】TiはNbと同様に微量含有させることにより
鋼の強度を上昇させる効果を有する。しかし、その含有
量が 0.010％未満では効果は小さく、一方、 0.100％を
超えると靱性が劣化するので、その含有量は 0.010〜0.
100 ％とする。Ti, like Nb, has the effect of increasing the strength of steel by containing a trace amount. However, if the content is less than 0.010%, the effect is small, while if it exceeds 0.100%, the toughness deteriorates, so the content is 0.010-0.
100%
【００２１】ＢはNbおよびTiと同様に微量含有させるこ
とにより鋼の強度を上昇させる効果を有する。しかし、
含有量が0.0010％未満ではその効果は小さく、一方、0.
0050％を超えると効果は飽和する。従って、Ｂ含有量は
0.0010〜0.0050％とする。B, like Nb and Ti, has the effect of increasing the strength of the steel by containing a trace amount. But,
If the content is less than 0.0010%, its effect is small, while on the other hand,
If it exceeds 0050%, the effect is saturated. Therefore, the B content is
It is set to 0.0010 to 0.0050%.
【００２２】本発明の鋼管を製造するには、上記の各成
分を含有する鋼をマンドレルミル法など通常の方法によ
り熱間圧延を行い、継目無鋼管とすればよい。この熱間
圧延のままの継目無鋼管は、引張強さが約 150〜180kgf
/mm2であり、−40〜−60℃程度の使用条件でも十分な靱
性を有している。しかも、熱処理を行う必要がないの
で、従来の熱処理鋼管に比べて製造コストが安い。In order to manufacture the steel pipe of the present invention, the steel containing each of the above components may be hot-rolled by a usual method such as a mandrel mill method to obtain a seamless steel pipe. This hot-rolled seamless steel pipe has a tensile strength of approximately 150 to 180 kgf.
/ mm 2 , and has sufficient toughness even under operating conditions of about -40 to -60 ° C. Moreover, since it is not necessary to perform heat treatment, the manufacturing cost is lower than that of the conventional heat treated steel pipe.
【００２３】[0023]
【実施例】表１に示す化学組成を有する鋼を、通常のマ
ンネスマン・マンドレルミルを用いて熱間圧延により継
目無鋼管（いずれも外径31.8mm、肉厚 2.6mm）に圧延
し、これらの鋼管について、引張試験（降伏点および引
張強さを測定）と低温落重試験を行った。[Examples] Steels having the chemical compositions shown in Table 1 were hot-rolled by a normal Mannesmann mandrel mill into seamless steel pipes (all having an outer diameter of 31.8 mm and a wall thickness of 2.6 mm). A tensile test (yield point and tensile strength was measured) and a low temperature drop weight test were performed on the steel pipe.
【００２４】低温落重試験では、前記の継目無鋼管から
切り出した長さ１ｍの鋼管を試験片とし、これらの試験
片を所定の温度に冷却し、支点間距離を 800mmとして水
平に支持し、その中央部に高さ３ｍから重さ 150kgの重
錘を落下させることにより瞬間的 (衝撃的) に応力を負
荷して試験片が脆性的な折損を生ずるか否かを判定し
た。In the low temperature drop weight test, steel pipes having a length of 1 m cut out from the seamless steel pipe were used as test pieces, and these test pieces were cooled to a predetermined temperature and horizontally supported with a fulcrum distance of 800 mm, It was determined whether a weight of 150 kg was dropped from a height of 3 m to the center of the test piece to instantaneously (impact) load the test piece to cause brittle breakage.
【００２５】試験結果を表２に示す。低温落重試験の欄
において、○印は鋼管試験片が延性変形したことを、×
印は鋼管試験片が脆性的に折損したことをあらわす。The test results are shown in Table 2. In the column of low temperature drop weight test, ○ indicates that the steel pipe test piece was ductile deformed, ×
The mark indicates that the steel pipe test piece was brittlely broken.
【００２６】表２の結果から、本発明の鋼管は、150kgf
/mm2を超える高強度を有するとともに、−100 ℃でも脆
性的な折損を生ずることなく、優れた靱性を示すことが
わかる。From the results shown in Table 2, the steel pipe of the present invention is 150 kgf.
It can be seen that it has a high strength of more than / mm 2 and exhibits excellent toughness without causing brittle breakage even at -100 ° C.
【００２７】[0027]
【表１】 [Table 1]
【００２８】[0028]
【表２】 [Table 2]
【００２９】[0029]
【発明の効果】本発明の継目無鋼管は、高い強度と優れ
た靱性を有し、特に、近年開発が進みつつある自動車の
鋼管製ドア補強材として、あるいはその他の機械構造用
部材として好適な鋼管である。INDUSTRIAL APPLICABILITY The seamless steel pipe of the present invention has high strength and excellent toughness and is particularly suitable as a steel pipe door reinforcing material for automobiles, which is being developed in recent years, or as a member for other mechanical structures. It is a steel pipe.
【００３０】[0030]
Claims (2)
〜0.50％、Mn：0.50〜2.00％、Cr：1.00〜3.00％、Mo：
0.10〜1.00％、Al： 0.005〜0.050 ％、Nb：0.005〜0.0
50 ％を含有し、残部がFeおよび不可避不純物からな
り、不純物中のＰが 0.025％以下、Ｓが 0.015％以下、
Ｏが0.0010％以下である高靱性継目無鋼管。1. By weight%, C: 0.15 to 0.40%, Si: 0.05
~ 0.50%, Mn: 0.50 ~ 2.00%, Cr: 1.00 ~ 3.00%, Mo:
0.10 to 1.00%, Al: 0.005 to 0.050%, Nb: 0.005 to 0.0
It contains 50% and the balance is Fe and unavoidable impurities. P in the impurities is 0.025% or less, S is 0.015% or less,
High toughness seamless steel pipe with O content of 0.0010% or less.
量％で、Ni：1.00〜3.00％、Ｖ：0.02〜0.10％、Ti：
0.010〜0.100 ％およびＢ：0.0010〜0.0050％のうちの
１種以上を含有し、残部がFeおよび不可避不純物からな
り、不純物中のＰが0.025 ％以下、Ｓが 0.015％以下、
Ｏが0.0010％以下である高靱性継目無鋼管。2. In addition to the components according to claim 1, further, in weight%, Ni: 1.00 to 3.00%, V: 0.02 to 0.10%, Ti:
0.010% to 0.100% and B: 0.0010% to 0.0050%, the balance being Fe and inevitable impurities, P in the impurities is 0.025% or less, S is 0.015% or less,
High toughness seamless steel pipe with O content of 0.0010% or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3102371A JP2669178B2 (en) | 1991-05-08 | 1991-05-08 | High toughness and high strength seamless steel pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3102371A JP2669178B2 (en) | 1991-05-08 | 1991-05-08 | High toughness and high strength seamless steel pipe |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0551699A true JPH0551699A (en) | 1993-03-02 |
| JP2669178B2 JP2669178B2 (en) | 1997-10-27 |
Family
ID=14325605
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3102371A Expired - Lifetime JP2669178B2 (en) | 1991-05-08 | 1991-05-08 | High toughness and high strength seamless steel pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2669178B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010061882A1 (en) * | 2008-11-26 | 2010-06-03 | 住友金属工業株式会社 | Seamless steel pipe and method for manufacturing same |
| CN113846262A (en) * | 2020-06-28 | 2021-12-28 | 宝山钢铁股份有限公司 | Seamless steel tube for automobile integral hollow transmission half shaft and manufacturing method thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103556069B (en) * | 2013-11-04 | 2016-02-17 | 洛阳双瑞特种装备有限公司 | A kind of gas cylinder seamless large-diameter pipes and manufacture method thereof |
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| JPS5441013A (en) * | 1977-09-08 | 1979-03-31 | Nec Corp | Coding/decoding unit for narrow-band color television signal |
| JPS5528331A (en) * | 1978-08-18 | 1980-02-28 | Nippon Steel Corp | Manufacture of hot rolled steel plate of high cleanliness and low yield ratio |
| JPS6296653A (en) * | 1981-10-20 | 1987-05-06 | Daido Steel Co Ltd | Non-tempered structural steel |
| JPH02101145A (en) * | 1988-10-06 | 1990-04-12 | Sumitomo Metal Ind Ltd | Water-cooled-type tmcp steel stock and large-diameter steel pipe and welding executing method therefor |
-
1991
- 1991-05-08 JP JP3102371A patent/JP2669178B2/en not_active Expired - Lifetime
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5435816A (en) * | 1977-08-26 | 1979-03-16 | Kawasaki Steel Co | Method of making steel sheets having good unstableebreakage characteristic |
| JPS5441013A (en) * | 1977-09-08 | 1979-03-31 | Nec Corp | Coding/decoding unit for narrow-band color television signal |
| JPS5528331A (en) * | 1978-08-18 | 1980-02-28 | Nippon Steel Corp | Manufacture of hot rolled steel plate of high cleanliness and low yield ratio |
| JPS6296653A (en) * | 1981-10-20 | 1987-05-06 | Daido Steel Co Ltd | Non-tempered structural steel |
| JPH02101145A (en) * | 1988-10-06 | 1990-04-12 | Sumitomo Metal Ind Ltd | Water-cooled-type tmcp steel stock and large-diameter steel pipe and welding executing method therefor |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010061882A1 (en) * | 2008-11-26 | 2010-06-03 | 住友金属工業株式会社 | Seamless steel pipe and method for manufacturing same |
| JP4475440B1 (en) * | 2008-11-26 | 2010-06-09 | 住友金属工業株式会社 | Seamless steel pipe and manufacturing method thereof |
| US8317946B2 (en) | 2008-11-26 | 2012-11-27 | Sumitomo Metal Industries, Ltd. | Seamless steel pipe and method for manufacturing the same |
| CN113846262A (en) * | 2020-06-28 | 2021-12-28 | 宝山钢铁股份有限公司 | Seamless steel tube for automobile integral hollow transmission half shaft and manufacturing method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2669178B2 (en) | 1997-10-27 |
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