JP2960771B2 - Door guard bar with excellent crushing strength - Google Patents
Door guard bar with excellent crushing strengthInfo
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- JP2960771B2 JP2960771B2 JP30996990A JP30996990A JP2960771B2 JP 2960771 B2 JP2960771 B2 JP 2960771B2 JP 30996990 A JP30996990 A JP 30996990A JP 30996990 A JP30996990 A JP 30996990A JP 2960771 B2 JP2960771 B2 JP 2960771B2
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Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は自動車のドアー補強パイプ（ドアーガードバ
ー）用部材に係り、より詳しくは、鋼板を溶接したパイ
プ品において優れた圧壊強度を示す自動車のドアーガー
ドバーに関するものである。Description: TECHNICAL FIELD The present invention relates to a member for a door reinforcing pipe (door guard bar) of an automobile, and more particularly, to an automobile having excellent crushing strength in a pipe product obtained by welding a steel plate. It is about door guard bar.
（従来の技術及び解決しようとする課題） 自動車車体の燃費向上及び衝撃時の安全時の安全性向
上のために自動車補強材の高強度化、軽量化が推進され
ている。(Related Art and Problems to be Solved) Higher strength and lighter weight of automobile reinforcing materials are being promoted in order to improve fuel efficiency of automobile bodies and safety in the event of safety in the event of an impact.
特に、ドア補強用部材には、従来より、100kgf/mm2級
のプレス品が主として使用されているが、最近、CAMP−
ISIJ Vol.2（1989）−2023に記載されているような、よ
り強度の高いパイプ材が、軽量化の点で有利なため、使
用されるようになった。In particular, the door reinforcement member, conventionally, although 100 kgf / mm 2 class pressed product is mainly used recently, cAMP-
Higher strength pipe materials as described in ISIJ Vol. 2 (1989) -2023 have been used because of their advantages in terms of weight reduction.
このようなパイプ品でプレス品と同様の吸収エネルギ
ーを得るためには、従来の60kgf/mm2程度の薄鋼板を電
縫溶接してから、引き続き高周波加熱などを施して、オ
ーステナイト温度域から急冷して製造されている。Thus in order to obtain the same absorption energy and pressed product in a pipe products, the conventional 60 kgf / mm 2 approximately of the thin steel sheet after electric resistance welding, subsequently subjected to high-frequency heating, rapid cooling from the austenite temperature region It is manufactured.
しかし、このように急冷した材料が用いられているも
のの、この材料の降伏点は低く、このため圧壊荷重や吸
収エネルギーは低い。However, although such a quenched material is used, the yield point of the material is low, so that the crushing load and the absorbed energy are low.
通常、このようなパイプ状に成形された鋼材の圧壊特
性は、同じ強度の場合には、降伏応力と強度の比である
降伏比によって決まるもので、降伏比の低い材料ほど、
圧壊荷重や吸収エネルギーが低い。したがって、圧壊特
性を高めるためには、降伏比を高めることが必要であ
る。Normally, the crushing properties of such a pipe-shaped steel material are determined by the yield ratio, which is the ratio of yield stress to strength, for the same strength, and the lower the yield ratio, the lower the material
Low crush load and absorbed energy. Therefore, it is necessary to increase the yield ratio in order to enhance the crushing characteristics.
本発明は、上記従来技術の欠点を解消して、圧壊強度
を高めることができたドアーガードバーを提供すること
を目的とする。SUMMARY OF THE INVENTION An object of the present invention is to provide a door guard bar which can solve the above-mentioned disadvantages of the prior art and can increase the crushing strength.
（課題を解決するための手段） 本発明者らは、前記課題を解決するために、薄鋼板を
電縫溶接したパイプの圧壊特性の改善策について鋭意研
究を重ねた結果、ここに本発明をなしたものである。(Means for Solving the Problems) In order to solve the above-mentioned problems, the present inventors have conducted intensive studies on measures to improve the crushing characteristics of a pipe formed by electric resistance welding of a thin steel plate, and as a result, the present invention has been described herein. What was done.
すなわち、本発明は、以下の（ａ）群のすべての元素
を含み、更に（ｂ）群及び（ｃ）群のうちの少なくとも
１種以上の元素を含み、 （ａ）C:0.1〜0.3％、Si:0.1〜0.5％、Mn:1.35〜3.0
％、Ｐ≦0.1％、sol.A:0.01〜0.1％、 （ｂ）Ti≦0.04％、Nb:0.04％、 Ｖ≦0.1％、 （ｃ）Mo≦0.5％、Ni≦:0.5％、 Cr≦0.5％、Cu≦0.5％、 Ｗ≦0.5％、Ｂ≦50ppm 残部が鉄及び不可避不純物よりなる組成を有する高張
力鋼板を用い、これを電縫管に製管し、焼入れ後、200
〜500℃の焼き戻しによって引張強さ100kgf/mm2以上、
降伏比0.80以上としたものであることを特徴とする圧壊
強度の優れたドアーガードバーを要旨とするものであ
る。That is, the present invention includes all the elements of the following group (a), and further includes at least one or more elements of the groups (b) and (c): (a) C: 0.1 to 0.3% , Si: 0.1-0.5%, Mn: 1.35-3.0
%, P ≦ 0.1%, sol.A: 0.01-0.1%, (b) Ti ≦ 0.04%, Nb: 0.04%, V ≦ 0.1%, (c) Mo ≦ 0.5%, Ni ≦: 0.5%, Cr ≦ 0.5%, Cu ≤ 0.5%, W ≤ 0.5%, B ≤ 50 ppm A high-strength steel sheet having a balance of iron and unavoidable impurities is used, and is made into an electric resistance welded pipe.
Tensile strength by tempering of ~500 ℃ 100kgf / mm 2 or more,
The gist of the present invention is a door guard bar having an excellent crushing strength characterized by a yield ratio of 0.80 or more.
以下に本発明を更に詳述する。 Hereinafter, the present invention is described in more detail.
（作用） 本発明に係る自動車ドア補強パイプ用高張力鋼板は、
前述の成分組成並びに特性を有するが、この鋼板の製造
工程は特に制限されるものではない。すなわち、該成分
組成の鋼を熱間圧延、又は冷間圧延した後の鋼板、或い
は冷間圧延後に焼鈍した鋼板を電縫溶接によってパイプ
とし、この焼入れ後に200〜500℃の温度で焼き戻しを施
すことにより、降伏比を上げ、パイプの圧壊特性を向上
させることができる。(Function) The high-strength steel sheet for an automobile door reinforcing pipe according to the present invention comprises:
Although having the above-described component composition and characteristics, the manufacturing process of this steel sheet is not particularly limited. That is, the steel of the component composition is hot-rolled, or a steel plate after cold rolling, or a steel plate annealed after cold rolling is made into a pipe by electric resistance welding, and after this quenching, tempered at a temperature of 200 to 500 ° C. By applying, the yield ratio can be increased and the crushing characteristics of the pipe can be improved.
まず、本発明における化学成分の限定理由について述
べる。First, the reasons for limiting the chemical components in the present invention will be described.
C:0.1〜0.3％ Ｃは鋼板の強度を高めるために極めて重要な元素であ
るが、Ｃ量が0.1％よりも少ないと、100kgf/mm2以上の
引張強度が得られない。また、0.3％を超えて過多に添
加すると溶接部が脆くなり、圧壊時に割れが生じ、所定
の吸収エネルギーが得られない。よつて、Ｃ量は0.1〜
0.3％の範囲とする。C: 0.1 to 0.3% C is an extremely important element for increasing the strength of the steel sheet. However, if the C content is less than 0.1%, a tensile strength of 100 kgf / mm 2 or more cannot be obtained. On the other hand, if it is added in excess of 0.3%, the welded portion becomes brittle, cracks occur during crushing, and the predetermined absorbed energy cannot be obtained. Therefore, the amount of C is 0.1 ~
The range is 0.3%.
Si:0.2〜0.5％ Siは鋼の降伏強度を高めるのに有効な元素であるが、
0.2％よりも少ないとその効果が得られない。また、0.5
％を超えて添加すると溶接部での欠陥が増し、圧壊時に
割れを生ずる。よって、Si量は0.2〜0.5％の範囲とす
る。Si: 0.2-0.5% Si is an effective element to increase the yield strength of steel,
If it is less than 0.2%, the effect cannot be obtained. Also, 0.5
If it is added in excess of%, defects in the welded portion increase and cracks occur during crushing. Therefore, the amount of Si is set in the range of 0.2 to 0.5%.
Mn:1.35〜3.0％ Mnは強化能が高い低温変態生成物を得るために必要
で、その添加量が1.35％よりも少ないと、低温変態生成
物を得るための熱処理（焼入れ、焼戻し）での急冷開始
温度が高くなり、鋼板の形状不良が発生する。また、3.
0％を超えると偏析が大きくなり、パイプ溶接部のメタ
ルフローが悪くなり、圧壊時に割れが生じて所定の吸収
エネルギーが得られない。よって、Mn量は1.35〜3.0％
の範囲とする。Mn: 1.35 ~ 3.0% Mn is necessary to obtain a low-temperature transformation product with high strengthening ability, and if the addition amount is less than 1.35%, heat treatment (quenching, tempering) to obtain a low-temperature transformation product The quenching start temperature increases, and the shape of the steel sheet becomes defective. Also, 3.
If it exceeds 0%, segregation increases, the metal flow in the welded portion of the pipe deteriorates, and cracks occur at the time of crushing, so that a predetermined absorbed energy cannot be obtained. Therefore, Mn content is 1.35 ~ 3.0%
Range.
P:0.1％以下 Ｐは、Siと同様、鋼の降伏強度を高めるのに有効な元
素であるが、0.1％を超えて添加すると溶接部が脆化し
て圧壊時に割れを生じるので、Ｐ量は0.1％以下とす
る。P: 0.1% or less P, like Si, is an effective element for increasing the yield strength of steel. However, if added in excess of 0.1%, the weld becomes brittle and cracks during crushing. 0.1% or less.
sol.A:0.01〜0.1％ Ａは、溶鋼の脱酸のために添加するが、0.01％未満
ではその効果は認められず、これ以上の添加が必要であ
り、しかし0.1％を超えて添加すると製品の表面疵が増
加して製品価値を減少させるので、Ａはsol.A量で
0.01〜0.1％の範囲とする。sol.A: 0.01-0.1% A is added for deoxidation of molten steel. However, if less than 0.01%, its effect is not recognized, further addition is necessary, but if added more than 0.1% Since the surface flaw of the product increases and the product value decreases, A
The range is 0.01 to 0.1%.
以上の（ａ）群の元素を含むほか、以下の元素のうち
の少なくとも１種以上を適量にて添加する必要がある。In addition to the elements of the above group (a), it is necessary to add at least one of the following elements in an appropriate amount.
Ti≦0.04％、Nb:0.04％、Ｖ≦0.1％ Ti、Nb及びＶは、炭、窒化物を形成し、鋼を強化して
降伏比を高める元素であるが、Ti、Nbの場合、それぞれ
0.04％を超えると、またＶの場合、0.1％を超えると、
そのような効果が飽和する。よって、Ti量は0.04％以
下、Nb量は0.04％以下、Ｖ量は0.1％以下とする。Ti ≤ 0.04%, Nb: 0.04%, V ≤ 0.1% Ti, Nb and V are elements that form carbon and nitride, strengthen steel and increase the yield ratio, but in the case of Ti and Nb,
If it exceeds 0.04%, and in the case of V, it exceeds 0.1%,
Such effects saturate. Therefore, the Ti content is 0.04% or less, the Nb content is 0.04% or less, and the V content is 0.1% or less.
Mo:0.5％ Moは鋼の焼入れ性を向上させると共に、溶接後はホワ
イトバンド層に多く存在し、この層の強度を高める効果
がある。しかし、0.5％を超えて添加しても、その効果
は飽和するため、経済性の点からMo量は0.5％以下とす
る。Mo: 0.5% Mo improves the hardenability of steel and is present in a large amount in the white band layer after welding, and has the effect of increasing the strength of this layer. However, even if it is added in excess of 0.5%, the effect is saturated, so the amount of Mo is set to 0.5% or less from the viewpoint of economy.
Ni:0.5％以下 Niは鋼の焼入れ性を向上させ、溶接部のホワイトバン
ドのAc3点を低下させ、この部分の強度低下を防止する
効果がある。しかし、0.5％を超えて添加しても、その
効果は飽和するため、経済性の点からNi量は0.5％以下
とする。Ni: 0.5% or less Ni has the effect of improving the hardenability of steel, lowering the Ac 3 point of the white band at the welded portion, and preventing the strength of this portion from decreasing. However, even if added over 0.5%, the effect is saturated, so the Ni content is set to 0.5% or less from the viewpoint of economy.
Cr:0.5％以下 Crは溶接部の焼入れ性を高め、この部分の強度低下を
防止する効果があるが、0.5％を超えてと造管時の溶接
部にペネトレーターが発生し易くなるので、Cr量は0.5
％以下とする。Cr: 0.5% or less Cr enhances the hardenability of the welded portion and has the effect of preventing the strength from being reduced in this portion. However, if it exceeds 0.5%, a penetrator is likely to be generated in the welded portion at the time of pipe making. The quantity is 0.5
% Or less.
Cu:0.5％以下 Cuは焼き戻し処理中に鋼中にε−Cuとして析出し、そ
の強度を向上させる効果がある。また、溶接部のホワイ
トバンドのAc3点を下げると共にこの部分に残存して溶
接部の強度低下を防ぎ、圧壊時におけるこの部分からの
破壊を防止する。しかし、0.5％を超えて添加しても、
その効果は飽和するため、経済性の点からCu量は0.5％
以下とする。Cu: 0.5% or less Cu precipitates as ε-Cu in the steel during tempering, and has the effect of improving its strength. Further, the Ac 3 point of the white band of the welded portion is lowered, and remains at this portion to prevent a decrease in the strength of the welded portion, thereby preventing breakage from this portion at the time of crush. However, even if it exceeds 0.5%,
Since the effect is saturated, the amount of Cu is 0.5% in terms of economy.
The following is assumed.
Ｗ≦0.5％以下 Ｗは炭、窒化物を形成して降伏強度を上げると共に、
溶接後はホワイトバンドの強度低下を防止する効果があ
る。しかし、0.5％を超えて添加しても、その効果は飽
和するため、経済性の点からＷ量は0.5％以下とする。W ≦ 0.5% or less W increases the yield strength by forming carbon and nitride,
After welding, it has the effect of preventing the strength of the white band from decreasing. However, even if it is added in excess of 0.5%, the effect is saturated, so that the W content is 0.5% or less from the viewpoint of economy.
B:50ppm以下 Ｂは焼入れ性を増す元素であり、このため、溶接部の
強度低下を防止する効果があるが、50ppmを超えるとそ
の効果が飽和するので、Ｂ量は50ppm以下とする。B: 50 ppm or less B is an element that increases the hardenability, and thus has an effect of preventing the strength of the welded portion from decreasing. However, if the content exceeds 50 ppm, the effect is saturated, so the B content is set to 50 ppm or less.
各元素の限定理由は以下のとおりであるが、上述の
（ａ）群の元素は、焼入れや焼き戻しを行うことによ
り、マルテンサイト、ベイナイトなどの低温変態生成物
を形成し、更にフェライトを含む複合組織を形成して10
0kgf/mm2以上の高強度を得るためのものであり、（ｂ）
群の元素はそれに更に析出効果を加える元素である。ま
た（ｃ）群の元素には溶接部の硬度低下を防ぐ効果があ
る。The reasons for limiting each element are as follows, but the elements in the above-mentioned group (a) form low-temperature transformation products such as martensite and bainite by quenching or tempering, and further contain ferrite. Forming a composite tissue 10
(B) for obtaining high strength of 0 kgf / mm 2 or more
The elements of the group are the elements that add a further precipitating effect to it. In addition, the elements of the group (c) have an effect of preventing a decrease in the hardness of the welded portion.
すなわち、これらの元素を添加しない場合には溶接部
にホワイトバンド（第１図参照）とよばれる炭素量の少
ない領域が生じ、第２図に示すとおり、溶接部の強度を
著しく低下させるが、これらの元素の添加により、この
ような強度低下を防ぐことができる。溶接部が弱い場合
には、圧壊時に熱影響部での変形が大きくなり、圧壊時
に座屈が生じて所定の吸収エネルギーが得られない。That is, when these elements are not added, a region having a small amount of carbon called a white band (see FIG. 1) occurs in the welded portion, and as shown in FIG. 2, the strength of the welded portion is significantly reduced. By adding these elements, such a decrease in strength can be prevented. When the welded portion is weak, the deformation in the heat-affected zone becomes large at the time of crushing, and buckling occurs at the time of crushing, so that a predetermined absorbed energy cannot be obtained.
パイプの圧壊強度や吸収エネルギーは降伏強度、板厚
及びパイプ径によって決まる。したがって、軽量化を図
るためには降伏強度をできるだけ高くするとよい（第４
図参照）。しかし、降伏比が低い場合、降伏強度の高い
材料を作るには、引張強度も非常に高くなる。したがっ
て、強化元素の添加量も多くなり、更には強度が高いた
めパイプ切断工具の損傷を高める。このため、降伏比は
0.80以上が必要である。この降伏比を向上させる方法と
しては、予め母材の組織をマルテンサイト、ベイナイト
などにしておき、これを焼き戻す方法により、必要な降
伏強度と伸びが得られ、十分な圧壊荷重と吸収エネルギ
ーが得られる。つまり、第５図に示すように、およそ20
0〜450℃の焼き戻しを施すことで達成される。The crushing strength and absorbed energy of a pipe are determined by the yield strength, plate thickness and pipe diameter. Therefore, in order to reduce the weight, the yield strength should be as high as possible (fourth example).
See figure). However, when the yield ratio is low, the tensile strength becomes very high to produce a material having a high yield strength. Therefore, the addition amount of the reinforcing element is increased, and the strength is high, so that the damage of the pipe cutting tool is increased. Therefore, the yield ratio is
0.80 or more is required. As a method of improving the yield ratio, the structure of the base material is made martensite, bainite, etc. in advance, and the necessary yield strength and elongation are obtained by tempering the structure. can get. That is, as shown in FIG.
This is achieved by performing tempering at 0 to 450 ° C.
なお、電縫溶接、焼き入れ条件、パイプ材の寸法等は
特に制限されない。In addition, the electric resistance welding, quenching conditions, dimensions of the pipe material, and the like are not particularly limited.
次に本発明の実施例を示す。 Next, examples of the present invention will be described.
（実施例） 第１表に示す化学成分を有する鋼を真空溶製し、通常
の方法で熱延、冷延、焼鈍を行って板厚1.8mmの鋼板を
得た。(Examples) Steel having the chemical components shown in Table 1 was vacuum-melted, and hot-rolled, cold-rolled, and annealed in a usual manner to obtain a steel sheet having a thickness of 1.8 mm.
また、この鋼板を電縫溶接により直径31.8mmのパイプ
に製管した。This steel sheet was formed into a 31.8 mm diameter pipe by electric resistance welding.
製管前の鋼板について焼入れし、第２表に示す温度の
焼戻しを施して機械的性質を調査した。また、製管した
パイプについて焼入れし、第２表に示す温度の焼戻しを
施して圧壊強度、吸収エネルギーを調査した。The steel sheet before pipe making was quenched and tempered at the temperatures shown in Table 2 to investigate the mechanical properties. Further, the produced pipes were quenched and tempered at the temperatures shown in Table 2 to investigate the crushing strength and the absorbed energy.
これらの調査結果を第２表に示す。 Table 2 shows the results of these surveys.
なお、圧壊試験は、パイプについて、第３図に示すよ
うに、スパン750mmで曲率150mmRの圧子を用いて試験を
行った。The crushing test was performed on the pipe using an indenter having a span of 750 mm and a curvature of 150 mmR as shown in FIG.
第２表より明らかなように、本発明例は、いずれも10
0kgf/mm2以上の高強度、降伏比0.80以上の高降伏比を示
し、しかも、第６図及び第７図に示すように圧壊強度が
高く、十分な吸収エネルギーが得られている。As is clear from Table 2, each of the examples of the present invention has
A high strength of 0 kgf / mm 2 or more, a high yield ratio of 0.80 or more, and a high crushing strength as shown in FIGS. 6 and 7, and sufficient absorbed energy are obtained.
第２図は鋼種No.2の熱処理材（焼戻し温度400℃）と
鋼種No.8の熱処理材（焼戻し温度400℃）における電縫
溶接部の硬さ分布を示したものであり、本発明材は溶接
部の強度が高いのに対し、比較材は強度が低い。Fig. 2 shows the hardness distribution of the electric resistance welded portion between the heat treated material of steel type No. 2 (tempering temperature 400 ° C) and the heat treated material of steel type No. 8 (tempering temperature 400 ° C). Has a high strength at the weld, whereas the comparative material has a low strength.
（発明の効果） 以上詳述したように、特定の組成を有する高張力鋼板
を用い、これを電縫溶接後に焼入れし、所定の温度で焼
戻しすることにより、マルテンサイト、ベイナイトなど
の低温変態生成物の単相又は複合相及び、それらに加え
てフェライトを含む複合組織からなる100kgf/mm2以上の
高強度で、高降伏比であり、優れた衝撃吸収エネルギー
を有し、圧壊強度に優れたドアーガードバーが得られ
た。 (Effects of the Invention) As described in detail above, a high-strength steel sheet having a specific composition is quenched after electric resistance welding and tempered at a predetermined temperature to produce low-temperature transformation of martensite, bainite, and the like. single-phase or composite phase of goods and, in 100 kgf / mm 2 or more high strength of a composite structure in addition to those containing the ferrite, a high yield ratio, has excellent impact absorption energy, excellent crushing strength A door guard bar is obtained.
第１図は電縫溶接部の金属組織（マクロ組織）を示す写
真、 第２図は電縫溶接部の硬さ分布を示す図、 第３図は圧壊試験の要領を示す説明図、 第４図（ａ）、（ｂ）はパイプの吸収エネルギー曲線を
示す図、 第５図は鋼の焼き戻し特性曲線を示す図、 第６図はパイプの吸収エネルギーと降伏比の関係を示す
図、 第７図はパイプの圧壊荷重と降伏比の関係を示す図であ
る。FIG. 1 is a photograph showing a metal structure (macro structure) of an ERW weld, FIG. 2 is a view showing a hardness distribution of an ERW weld, FIG. 3 is an explanatory view showing a procedure of a crush test, and FIG. Figures (a) and (b) show the absorbed energy curve of the pipe, Figure 5 shows the tempering characteristic curve of steel, Figure 6 shows the relationship between the absorbed energy of the pipe and the yield ratio, FIG. 7 is a diagram showing the relationship between the pipe crushing load and the yield ratio.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) C22C 38/00 - 38/60 ──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. 6 , DB name) C22C 38/00-38/60
Claims (1)
の全ての元素を含み、更に（ｂ）群及び（ｃ）群のうち
の少なくとも１種以上の元素を含み、 （ａ）C:0.1〜0.3％、Si:0.1〜0.5％、Mn:1.35〜3.0
％、Ｐ≦0.1％、sol.Al:0.01〜0.1％、 （ｂ）Ti≦0.04％、Nb:0.04％、Ｖ≦0.1％、 （ｃ）Mo≦0.5％、Ni≦:0.5％、Cr≦0.5％、Cu≦0.5
％、Ｗ≦0.5％、Ｂ≦50ppm 残部が鉄及び不可避不純物よりなる組成を有する高張力
鋼板を用い、これを電縫管に製管し、焼入れ後、200〜5
00℃の焼き戻しによって引張強さ100kgf/mm2以上、降伏
比0.80以上としたものであることを特徴とする圧壊強度
の優れたドアーガードバー。(1) In% by weight (hereinafter the same), it contains all the elements of the following group (a) and further contains at least one element of the groups (b) and (c): a) C: 0.1-0.3%, Si: 0.1-0.5%, Mn: 1.35-3.0
%, P ≦ 0.1%, sol.Al:0.01-0.1%, (b) Ti ≦ 0.04%, Nb: 0.04%, V ≦ 0.1%, (c) Mo ≦ 0.5%, Ni ≦: 0.5%, Cr ≦ 0.5%, Cu ≦ 0.5
%, W ≦ 0.5%, B ≦ 50 ppm A high-strength steel sheet having a composition consisting of iron and unavoidable impurities is used.
A door guard bar having excellent crushing strength, characterized by having a tensile strength of 100 kgf / mm 2 or more and a yield ratio of 0.80 or more by tempering at 00 ° C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30996990A JP2960771B2 (en) | 1990-11-15 | 1990-11-15 | Door guard bar with excellent crushing strength |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30996990A JP2960771B2 (en) | 1990-11-15 | 1990-11-15 | Door guard bar with excellent crushing strength |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04180537A JPH04180537A (en) | 1992-06-26 |
| JP2960771B2 true JP2960771B2 (en) | 1999-10-12 |
Family
ID=17999549
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30996990A Expired - Fee Related JP2960771B2 (en) | 1990-11-15 | 1990-11-15 | Door guard bar with excellent crushing strength |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2960771B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104781438A (en) * | 2012-11-14 | 2015-07-15 | 杰富意钢铁株式会社 | Automobile collision energy absorbing member and manufacturing method therefor |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4447604A1 (en) * | 1994-12-15 | 1996-09-12 | Mannesmann Ag | Door reinforcement element |
| JP5142068B2 (en) * | 2006-05-17 | 2013-02-13 | 日産自動車株式会社 | High strength steel plate for resistance spot welding and joining method thereof |
| CN101514433A (en) | 2007-03-16 | 2009-08-26 | 株式会社神户制钢所 | Automobile high-strength electric resistance welded steel pipe with excellent low-temperature impact property and method of manufacturing the same |
| WO2018147389A1 (en) * | 2017-02-13 | 2018-08-16 | 日新製鋼株式会社 | Method for manufacturing electroseamed metal tube, and electroseamed metal tube |
-
1990
- 1990-11-15 JP JP30996990A patent/JP2960771B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104781438A (en) * | 2012-11-14 | 2015-07-15 | 杰富意钢铁株式会社 | Automobile collision energy absorbing member and manufacturing method therefor |
| EP2921570A4 (en) * | 2012-11-14 | 2015-12-09 | Jfe Steel Corp | Automobile collision energy absorbing member and manufacturing method therefor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04180537A (en) | 1992-06-26 |
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