JPH0835036A - Cast and forged steel product for building construction, excellent in refractoriness - Google Patents
Cast and forged steel product for building construction, excellent in refractorinessInfo
- Publication number
- JPH0835036A JPH0835036A JP11671895A JP11671895A JPH0835036A JP H0835036 A JPH0835036 A JP H0835036A JP 11671895 A JP11671895 A JP 11671895A JP 11671895 A JP11671895 A JP 11671895A JP H0835036 A JPH0835036 A JP H0835036A
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- forged steel
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は柱、梁、柱と梁の接合金
物、柱脚金物、トラスのジョイント部材、支承金物、ブ
レスの接合部材等の建築構造用構築材に用いられる耐火
性の優れた建築構造用鋳・鍛鋼品に関する。BACKGROUND OF THE INVENTION The present invention relates to a fire resistant material used for building structures such as columns, beams, column-to-beam joining hardware, column pedestals, truss joint members, bearings, and breath joint members. It relates to excellent cast and forged steel products for building structures.
【０００２】[0002]
【従来の技術及び発明が解決しようとする課題】従来よ
り柱や梁等の建築構造用構築材として、溶接構造用圧延
鋼材（ＪＩＳＧ３１０６）等が使用されているが、これ
らの材料は高温時に耐力等の機械的性質の低下を招くこ
とから、耐火構造物では耐火材による被覆等の対処が必
要となり工事費、工期の面から経済的に不利となる問題
があった。2. Description of the Related Art Conventionally, rolled steel for welded structures (JISG3106) has been used as a building material for building structures such as columns and beams, but these materials have a high yield strength at high temperature. Since it causes deterioration of mechanical properties such as the above, there is a problem that it is economically disadvantageous in terms of construction cost and construction period because it is necessary to deal with the refractory structure such as coating with a refractory material.
【０００３】そこで、耐火被覆の削減又は省略を可能と
するため、高温においても高い耐力（６００℃での耐力
が常温耐力の２／３以上）を有する建築構造用圧延鋼材
が種々提案されている。例えば特公平４−５０３６２号
公報では、Ｃ：０．０４〜０．１５％、Ｓｉ：０．６％
以下、Ｍｎ：０．５〜１．６％、Ｎｂ：０．００５〜
０．０４％、Ｍｏ：０．４〜０．７％、Ａｌ：０．１％
以下、Ｎ：０．００１〜０．００６％、残部がＦｅ及び
不可避不純物からなる鋼片を１１００〜１３００℃の温
度域で加熱後、熱間圧延を８００〜１０００℃の温度範
囲で終了する耐火性の優れた建築用低降伏比鋼材の製造
方法が開示されている。これら熱間塑性加工によって製
造された鋼材は、複雑形状の建築構造用構築材を溶接な
しには製造ができない、また板厚が例えば５０ｍｍ以上
に厚くなると十分な低温靭性が得られない等の問題があ
る。Therefore, in order to reduce or omit the fireproof coating, various rolled steel materials for building structures have been proposed which have a high yield strength (a yield strength at 600 ° C. is 2/3 or more of a room temperature yield strength) even at a high temperature. . For example, in Japanese Examined Patent Publication No. 4-50362, C: 0.04 to 0.15%, Si: 0.6%
Hereinafter, Mn: 0.5 to 1.6%, Nb: 0.005 to
0.04%, Mo: 0.4-0.7%, Al: 0.1%
Hereinafter, N: 0.001 to 0.006%, the balance is Fe and a steel slab consisting of unavoidable impurities is heated in a temperature range of 1100 to 1300 ° C., and then hot rolling is finished in a temperature range of 800 to 1000 ° C. Disclosed is a method for producing a low yield ratio steel material having excellent properties for construction. The steel materials manufactured by these hot plastic workings cannot be manufactured without welding construction materials for building structures having complicated shapes, and sufficient low temperature toughness cannot be obtained when the plate thickness becomes thicker than 50 mm, for example. There is.
【０００４】本発明は、鋳造製または鍛造製によって一
体的に製造する建築構造用鋳・鍛鋼品の研究を重ねた結
果完成したもので、高温において高い耐力を有すると共
に、従来の溶接構造用圧延鋼材（ＪＩＳ Ｇ３１０６）
等と同等以上の常温特性（引張強さ、伸び、耐力）、溶
接性を備えた耐火性の優れた建築構造用鋳・鍛鋼品を提
供することを目的とする。The present invention was completed as a result of repeated research on cast and forged steel products for building structures, which are integrally manufactured by casting or forging, and has a high yield strength at high temperatures and the conventional rolling for welding structures. Steel material (JIS G3106)
It is an object of the present invention to provide a cast and forged steel product for building structures, which has room temperature characteristics (tensile strength, elongation, yield strength) and weldability equal to or higher than those of the above and excellent in fire resistance.
【０００５】[0005]
【課題を解決するための手段】本発明者等は、上記目的
を達成するために建築構造用鋳・鍛鋼品の化学成分、金
属組織及び熱処理等について研究を行った結果、（１）
ＭｏとＣの添加量を調整することにより、必要な靭性を
確保すると共に高温における耐力の低下が抑えられる。
（２）Ｎｂ、Ｔｉ、ＶをＭｏと共に添加することによ
り、炭素当量の増大を抑え、かつ組織の微細化が促進さ
れ高温における耐力の低下が著しく抑えられる。（３）
化学成分を適正に調整したうえで、９００〜１０００℃
の焼入れ冷却し、次いで７５０〜８５０℃の焼入れ後、
５００〜７００℃の焼戻しを施す、若しくは９００〜１
０００℃に加熱保持し、次いで７５０〜８５０℃で恒温
保持を施して、金属組織を所定面積％のフェライトと残
部ベーナイト及び／又はパーライトの混合組織とするこ
とにより、常温強度、靱性及び溶接性は従来の溶接構造
用圧延鋼材と同等以上であって、６００℃における耐力
が常温耐力の２／３以上を確保できることを見いだし
た。[Means for Solving the Problems] In order to achieve the above-mentioned objects, the present inventors have conducted research on the chemical composition, metallographic structure, heat treatment, etc. of cast and forged steel products for building structures, and as a result, (1)
By adjusting the addition amounts of Mo and C, the required toughness can be secured and the decrease in yield strength at high temperatures can be suppressed.
(2) By adding Nb, Ti, and V together with Mo, the increase of carbon equivalent is suppressed, and the refinement of the structure is promoted, so that the reduction of proof stress at high temperature is significantly suppressed. (3)
After properly adjusting the chemical composition, 900-1000 ℃
After quenching and cooling, and then quenching at 750 to 850 ° C,
Tempering at 500-700 ° C, or 900-1
By maintaining the temperature at 000 ° C. and then at 750 to 850 ° C., the metal structure is a mixed structure of ferrite having a predetermined area% and the balance bainite and / or pearlite, whereby room temperature strength, toughness and weldability are improved. It has been found that the yield strength at 600 ° C. is equal to or higher than that of the conventional rolled steel material for welded structure, and can secure 2/3 or more of the room temperature yield strength.
【０００６】上記知見に基づく本発明は、化学成分が重
量％で、Ｃ ：０．０５〜０．１５％、 Ｓｉ：
０．８％以下、Ｍｎ：０．５〜１．６％、 Ｐ
：０．０４％以下 Ｓ ：０．０４％以下 Ｍｏ：０．４〜
０．８％ Ｎｂ：０．００５〜０．０４％、 Ｔｉ：０．００５
〜０．１％を含有し、炭素当量Ｃｅｑ（％）＝Ｃ＋Ｓｉ
／２４＋Ｍｎ／６＋Ｎｉ／４０＋Ｃｒ／５＋Ｍｏ／４＋
Ｖ／１４が０．５％以下で、かつ金属組織が５５〜９０
面積％のフェライトと残部ベーナイト及び／又はパーラ
イトの混合組織からなることを特徴とする耐火性の優れ
た建築構造用鋳・鍛鋼品である。In the present invention based on the above findings, the chemical composition is wt%, C: 0.05 to 0.15%, Si:
0.8% or less, Mn: 0.5 to 1.6%, P
: 0.04% or less S: 0.04% or less Mo: 0.4 to
0.8% Nb: 0.005-0.04%, Ti: 0.005
~ 0.1%, carbon equivalent Ceq (%) = C + Si
/ 24 + Mn / 6 + Ni / 40 + Cr / 5 + Mo / 4 +
V / 14 is 0.5% or less, and the metal structure is 55 to 90.
A cast and forged steel product having excellent fire resistance, which is characterized by comprising a mixed structure of area% ferrite and the balance bainite and / or pearlite.
【０００７】また前記建築構造用鋳・鍛鋼品は、化学成
分が重量％で、Ｖ：０．００５〜０．１％をさらに含有
することができる。さらに、前記建築構造用鋳・鍛鋼品
は、９００〜１０００℃の焼入れ冷却し、次いで７５０
〜８５０℃の焼入れ後、５００〜７００℃の焼戻し、若
しくは９００〜１０００℃に加熱保持し、次いで７５０
〜８５０℃で恒温保持の熱処理を行うことにより、必要
な常温強度、靭性、溶接性及び高温耐力を確保できる。The cast and forged steel products for building structures may further contain V: 0.005 to 0.1% by weight in chemical composition. Further, the cast and forged steel product for building structure is quenched and cooled at 900 to 1000 ° C., and then 750
After quenching at ~ 850 ° C, tempering at 500 ~ 700 ° C, or heating and holding at 900 ~ 1000 ° C, then 750
By carrying out heat treatment at a constant temperature of 850 ° C., necessary room temperature strength, toughness, weldability and high temperature proof stress can be secured.
【０００８】[0008]
【作用】本発明の建築構造用鋳・鍛鋼品の化学成分の限
定理由は次の通りである。Ｃは強度向上に寄与する元素
であり、０．０５％未満では十分な強度を確保すること
ができず、０．１５％を超えると溶接性及び靭性が低下
するので、Ｃ量は０．０５〜０．１５％とした。The reason for limiting the chemical composition of the cast and forged steel product for building structure of the present invention is as follows. C is an element that contributes to the improvement of strength. If it is less than 0.05%, sufficient strength cannot be secured, and if it exceeds 0.15%, the weldability and toughness deteriorate, so the C content is 0.05. ˜0.15%.
【０００９】Ｓｉは製鋼時の脱酸剤及び強度向上に有効
な元素であり、０．８％を超えると溶接性及び靭性が低
下するので、Ｓｉ量は０．８％以下とした。Si is a deoxidizing agent during steel making and is an effective element for improving strength. If it exceeds 0.8%, the weldability and toughness deteriorate, so the amount of Si was made 0.8% or less.
【００１０】Ｍｎは製鋼時の脱酸剤及び強度向上に有効
な元素であり、０．５％未満ではこのような効果が小さ
く、また１．６％を超えると溶接性及び靭性が劣化する
ので、Ｍｎ量は０．５〜１．６％とした。Mn is an effective deoxidizer during steel making and is an effective element for improving strength. If it is less than 0.5%, such an effect is small, and if it exceeds 1.6%, weldability and toughness deteriorate. , Mn amount was 0.5 to 1.6%.
【００１１】Ｐ、Ｓは溶接性及び靭性劣化の原因となる
のでできるだけ低減することが望ましく、Ｐ量は０．０
４％以下、Ｓ量は０．０４％以下とした。Since P and S cause deterioration of weldability and toughness, it is desirable to reduce them as much as possible.
4% or less and the amount of S were 0.04% or less.
【００１２】Ｍｏは高温強度向上に有効な元素であり、
６００℃における耐力を著しく上昇させる。０．４％未
満ではこのような効果が小さく、０．８％を超えると凝
固中に偏析しやすくまた溶接性が劣化するので、Ｍｏ量
は０．４〜０．８％とした。Mo is an element effective for improving high temperature strength,
It significantly increases the yield strength at 600 ° C. If it is less than 0.4%, such an effect is small, and if it exceeds 0.8%, segregation is likely to occur during solidification and weldability is deteriorated. Therefore, the Mo content is set to 0.4 to 0.8%.
【００１３】Ｎｂは常温強度、高温強度及び組織の微細
化効果により靭性を向上させる。０．００５％未満では
このような効果が小さく、０．０４％を超えると凝固中
に偏析しやすく靭性の劣化を招くので、Ｎｂ量は０．０
０５〜０．０４％とした。Nb improves the toughness by the ordinary temperature strength, the high temperature strength and the effect of refining the structure. If it is less than 0.005%, such an effect is small, and if it exceeds 0.04%, segregation easily occurs during solidification, which causes deterioration of toughness, so the Nb content is 0.0
It was set to 05 to 0.04%.
【００１４】Ｔｉは高温強度の向上、溶接熱影響部のオ
ーステナイト粒の粗大化を抑制すると共に、微細フェラ
イトの生成促進により、溶接熱影響部の靭性向上に有効
な元素であるが、０．００５％未満ではこのような効果
が小さく、０．１％を超えると溶接性が劣化するので、
Ｔｉ量は０．００５〜０．１％とした。Ti is an element effective in improving the high temperature strength, suppressing the coarsening of austenite grains in the weld heat affected zone, and promoting the formation of fine ferrite, and is effective in improving the toughness of the weld heat affected zone. If it is less than 0.1%, such an effect is small, and if it exceeds 0.1%, the weldability deteriorates.
The amount of Ti was 0.005-0.1%.
【００１５】本発明では上記化学成分以外にＶ、Ｎｉ、
Ｃｒのうちいずれか１種又は２種以上を含有することが
できる。In the present invention, in addition to the above chemical components, V, Ni,
Any one or more of Cr may be contained.
【００１６】Ｖは常温強度、高温強度及び組織の微細化
効果により靭性を向上させる。０．００５％未満ではこ
のような効果が小さく、０．１％を超えると凝固中に偏
析しやすく靭性の劣化を招くので、Ｖ量は０．００５〜
０．１％とした。V improves the toughness by the ordinary temperature strength, the high temperature strength and the effect of refining the structure. If it is less than 0.005%, such an effect is small, and if it exceeds 0.1%, segregation easily occurs during solidification, which causes deterioration of toughness.
It was set to 0.1%.
【００１７】Ｎｉは強度及び靱性向上に有効な元素であ
り、高価なため１．０％以下が望ましい。また、Ｃｒは
高温強度の向上に有効な元素であり、０．７％を超える
と靱性及び溶接性が劣化するので、Ｃｒ量は０．７％以
下とした。Ni is an element effective for improving strength and toughness and is expensive, so 1.0% or less is desirable. Further, Cr is an element effective in improving the high temperature strength, and if it exceeds 0.7%, the toughness and weldability deteriorate, so the Cr content was made 0.7% or less.
【００１８】本発明の建築構造用鋳・鍛鋼品は炭素当量
Ｃｅｑ（％）＝Ｃ＋Ｓｉ／２４＋Ｍｎ／６＋Ｎｉ／４０
＋Ｃｒ／５＋Ｍｏ／４＋Ｖ／１４を０．５％以下に規定
する。炭素当量が０．５％を超えると、溶接熱影響部が
硬化して溶接割れや使用中の損傷原因となることがある
ためである。The cast and forged steel product for building structure of the present invention has a carbon equivalent Ceq (%) = C + Si / 24 + Mn / 6 + Ni / 40.
+ Cr / 5 + Mo / 4 + V / 14 is specified to 0.5% or less. This is because if the carbon equivalent exceeds 0.5%, the heat-affected zone of the weld may harden and cause weld cracking or damage during use.
【００１９】また本発明の建築構造用鋳・鍛鋼品は、圧
延鋼材と比べ各部の厚みが大きくなることが多く、鋳型
内での溶湯の冷却速度の低下により機械的性質が低下す
るので、鋳・鍛鋼品内部の結晶粒の微細化のために、９
００〜１０００℃の焼入れ冷却し、次いで７５０〜８５
０℃の焼入れ後、５００〜７００℃の焼戻し、若しくは
９００〜１０００℃に加熱保持し、次いで７５０〜８５
０℃で恒温保持の熱処理を行う。この熱処理により得ら
れた建築構造用鋳・鍛鋼品の金属組織は、５５〜９０面
積％のフェライトと残部ベーナイト及び／又はパーライ
トの混合組織からなり、常温耐力と６００℃の高温耐力
の特性バランスを良好にとることができる。常温におけ
る靭性の向上のためにフェライトは５５〜９０面積％必
要であり、また残部のベーナイト及び／又はパーライト
は高温耐力を著しく向上させる。Further, in the cast and forged steel product for building structure of the present invention, the thickness of each part is often larger than that of the rolled steel material, and the mechanical properties deteriorate due to the decrease of the cooling rate of the molten metal in the mold.・ To refine the crystal grains inside the forged steel,
Quenched and cooled at 00-1000 ° C, then 750-85
After quenching at 0 ° C, tempering at 500 to 700 ° C, or heating and holding at 900 to 1000 ° C, and then 750 to 85
Heat treatment is performed at a constant temperature of 0 ° C. The metal structure of the cast and forged steel product for building structure obtained by this heat treatment is composed of a mixed structure of 55 to 90 area% of ferrite and the balance bainite and / or pearlite, and has a property balance between room temperature proof stress and high temperature proof stress of 600 ° C. It can be taken well. In order to improve the toughness at room temperature, 55 to 90 area% of ferrite is required, and the balance bainite and / or pearlite remarkably improves the high temperature yield strength.
【００２０】[0020]
【実施例】周知の高周波溶解炉で表１に示す化学成分の
供試材（本発明材Ｎｏ．１〜３）をそれぞれ溶解した
後、幅１３０ｍｍ×長さ２７０ｍｍ×高さ１６０ｍｍの
キールブロック鋳型に鋳造した。鋳型から取り出し後、
９３０℃の焼入れ冷却し、次いで８００℃の焼入れ後、
６２５℃の焼戻し熱処理を施した。この供試材から引張
試験片を採取し、機械的性質（常温における引張強さ、
伸び及び０．２％耐力、６００℃における引張強さ及び
０．２％耐力）と金属組織（フェライトの面積％、ベー
ナイト及びパーライトの面積％）を測定調査した。その
結果を表２に示す。なお表１において、化学成分は重量
％で表わし、残部は実質的にＦｅである。また、炭素当
量Ｃｅｑ（％）＝Ｃ＋Ｓｉ／２４＋Ｍｎ／６＋Ｎｉ／４
０＋Ｃｒ／５＋Ｍｏ／４＋Ｖ／１４、溶接割れ感受性組
成Ｐｃｍ（％）＝Ｃ＋Ｓｉ／３０＋Ｍｎ／２０＋Ｃｕ／
２０＋Ｎｉ／６０＋Ｃｒ／２０＋Ｍｏ／１５＋Ｖ／１６
＋５Ｂを表わす。EXAMPLE A keel block mold having a width of 130 mm, a length of 270 mm, and a height of 160 mm was melted in a known high-frequency melting furnace after melting each of the test materials (invention materials Nos. 1 to 3) having the chemical components shown in Table 1. Cast into. After removing from the mold,
After quenching at 930 ° C and cooling, then quenching at 800 ° C,
A tempering heat treatment at 625 ° C. was performed. Tensile test pieces were taken from this test material and the mechanical properties (tensile strength at normal temperature,
The elongation and 0.2% proof stress, the tensile strength at 600 ° C. and the 0.2% proof stress) and the metal structure (area% of ferrite, area% of bainite and pearlite) were measured and investigated. The results are shown in Table 2. In addition, in Table 1, the chemical composition is represented by weight%, and the balance is substantially Fe. Further, carbon equivalent Ceq (%) = C + Si / 24 + Mn / 6 + Ni / 4
0 + Cr / 5 + Mo / 4 + V / 14, weld crack sensitivity composition Pcm (%) = C + Si / 30 + Mn / 20 + Cu /
20 + Ni / 60 + Cr / 20 + Mo / 15 + V / 16
Represents + 5B.
【００２１】[0021]
【表１】 [Table 1]
【００２２】[0022]
【表２】 [Table 2]
【００２３】表１、表２から明らかなように本発明の建
築構造用鋳・鍛鋼品は、従来の溶接構造用圧延鋼材（Ｊ
ＩＳ Ｇ３１０６）に規定されるＳＭ４９０と比べて、
常温における引張強さ、伸び及び耐力、溶接性が同等以
上で、６００℃において常温耐力の２／３以上の耐力を
有している。As is clear from Tables 1 and 2, the cast and forged steel products for building structures of the present invention are conventional rolled steel materials for welded structures (J
Compared with SM490 specified in IS G3106),
The tensile strength, elongation and proof stress at room temperature are equal to or higher than the weldability, and the proof stress at 600 ° C. is ⅔ or more of the normal temperature proof stress.
【００２４】図１に本発明試験材Ｎｏ．１と従来の溶接
構造用圧延鋼材（ＪＩＳ Ｇ３１０６）に規定されるＳ
Ｍ４９０の各温度における引張強さを示す。また図２に
本発明試験材Ｎｏ．１と従来の溶接構造用圧延鋼材（Ｊ
ＩＳ Ｇ３１０６）に規定されるＳＭ４９０の各温度に
おける０．２％耐力を示す。図１、図２から明らかなよ
うに本発明の建築構造用鋳・鍛鋼品は、温度が上昇して
も引張強さと耐力が著しく低下しないことが確認でき
た。FIG. 1 shows the test material No. 1 of the present invention. 1 and S as specified in the conventional rolled steel for welded structure (JIS G3106)
The tensile strength of M490 at each temperature is shown. Further, in FIG. 1 and conventional rolled steel for welding structure (J
It shows 0.2% proof stress at each temperature of SM490 specified in IS G3106). As is clear from FIGS. 1 and 2, it was confirmed that the cast and forged steel products for building structures according to the present invention did not significantly decrease in tensile strength and proof stress even when the temperature increased.
【００２５】[0025]
【発明の効果】本発明によれば、常温における機械的性
質及び溶接性は従来の溶接構造用圧延鋼材と同等以上で
あって、６００℃における耐力が常温耐力の２／３以上
を確保できるので、耐火構造物等では耐火材による被覆
等の対処が不要となり工事費が大幅に削減でき、また工
期も短縮できる。According to the present invention, the mechanical properties and weldability at room temperature are equal to or higher than those of the conventional rolled steel for welded structure, and the yield strength at 600 ° C can be secured to be 2/3 or more of the room temperature yield strength. For refractory structures, etc., it is not necessary to take measures such as coating with refractory materials, which can significantly reduce construction costs and shorten the construction period.
【図１】本発明試験材Ｎｏ．１と従来材の各温度におけ
る引張強さを示すグラフである。BRIEF DESCRIPTION OF THE DRAWINGS FIG. It is a graph which shows the tensile strength in each temperature of 1 and the conventional material.
【図２】本発明試験材Ｎｏ．１と従来材の各温度におけ
る０．２％耐力を示すグラフである。FIG. 2 shows the test material No. of the present invention. It is a graph which shows 0.2% proof stress in each temperature of 1 and the conventional material.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 松尾 英成 北九州市若松区北浜一丁目９番１号 日立 金属株式会社若松工場内 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hidenari Matsuo 1-9-1 Kitahama, Wakamatsu-ku, Kitakyushu City Hitachi Metals Co., Ltd. Wakamatsu Plant
Claims (5)
０．１５％、 Ｓｉ：０．８％以下、Ｍｎ：０．５
〜１．６％、 Ｐ ：０．０４％以下 Ｓ ：０．０４％以下 Ｍｏ：０．４〜
０．８％ Ｎｂ：０．００５〜０．０４％、 Ｔｉ：０．００５
〜０．１％を含有し、炭素当量Ｃｅｑ（％）＝Ｃ＋Ｓｉ
／２４＋Ｍｎ／６＋Ｎｉ／４０＋Ｃｒ／５＋Ｍｏ／４＋
Ｖ／１４が０．５％以下で、かつ金属組織が５５〜９０
面積％のフェライトと残部ベーナイト及び／又はパーラ
イトの混合組織からなることを特徴とする耐火性の優れ
た建築構造用鋳・鍛鋼品。1. The chemical composition in% by weight, C: 0.05-.
0.15%, Si: 0.8% or less, Mn: 0.5
-1.6%, P: 0.04% or less S: 0.04% or less Mo: 0.4-
0.8% Nb: 0.005-0.04%, Ti: 0.005
~ 0.1%, carbon equivalent Ceq (%) = C + Si
/ 24 + Mn / 6 + Ni / 40 + Cr / 5 + Mo / 4 +
V / 14 is 0.5% or less, and the metal structure is 55 to 90.
A cast and forged steel product for building structure having excellent fire resistance, which is composed of a mixed structure of area% ferrite and the balance bainite and / or pearlite.
０．１％をさらに含有することを特徴とする請求項１に
記載の耐火性の優れた建築構造用鋳・鍛鋼品。2. The chemical composition in% by weight, V: 0.005-
The cast and forged steel product for building structure with excellent fire resistance according to claim 1, further containing 0.1%.
下、 Ｃｒ：０．７％以下のうちいずれか１種又は２
種をさらに含有することを特徴とする請求項１又は請求
項２に記載の耐火性の優れた建築構造用鋳・鍛鋼品。3. The chemical component, in% by weight, one of Ni: 1.0% or less and Cr: 0.7% or less, or 2
A cast and forged steel product for building structure having excellent fire resistance according to claim 1 or 2, further comprising a seed.
いで７５０〜８５０℃の焼入れ後、５００〜７００℃の
焼戻しをしたことを特徴とする請求項１〜３のいずれか
一に記載の耐火性の優れた建築構造用鋳・鍛鋼品。4. The fire resistance according to any one of claims 1 to 3, characterized by quenching and cooling at 900 to 1000 ° C., then quenching at 750 to 850 ° C., and then tempering at 500 to 700 ° C. Excellent cast and forged steel products for building structures.
で７５０〜８５０℃で恒温保持をしたことを特徴とする
請求項１〜３のいずれか一に記載の耐火性の優れた建築
構造用鋳・鍛鋼品。5. A casting for a building structure having excellent fire resistance according to claim 1, wherein the casting is carried out by heating at 900 to 1000 ° C. and then at 750 to 850 ° C.・ Forged steel products.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11671895A JPH0835036A (en) | 1994-05-18 | 1995-05-16 | Cast and forged steel product for building construction, excellent in refractoriness |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6-103967 | 1994-05-18 | ||
| JP10396794 | 1994-05-18 | ||
| JP11671895A JPH0835036A (en) | 1994-05-18 | 1995-05-16 | Cast and forged steel product for building construction, excellent in refractoriness |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0835036A true JPH0835036A (en) | 1996-02-06 |
Family
ID=26444528
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11671895A Pending JPH0835036A (en) | 1994-05-18 | 1995-05-16 | Cast and forged steel product for building construction, excellent in refractoriness |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0835036A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2019214753A (en) * | 2018-06-12 | 2019-12-19 | 日本製鉄株式会社 | Low-yield-ratio fire resistant steel plate |
| CN111763881A (en) * | 2020-06-19 | 2020-10-13 | 钢铁研究总院 | High-strength low-carbon bainite refractory steel and preparation method thereof |
-
1995
- 1995-05-16 JP JP11671895A patent/JPH0835036A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2019214753A (en) * | 2018-06-12 | 2019-12-19 | 日本製鉄株式会社 | Low-yield-ratio fire resistant steel plate |
| CN111763881A (en) * | 2020-06-19 | 2020-10-13 | 钢铁研究总院 | High-strength low-carbon bainite refractory steel and preparation method thereof |
| US11761050B2 (en) | 2020-06-19 | 2023-09-19 | Central Iron & Steel Research Institute | High-strength low-carbon bainitic fire-resistant steel and preparation method thereof |
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