JPS6317891B2 - - Google Patents
Info
- Publication number
- JPS6317891B2 JPS6317891B2 JP55024367A JP2436780A JPS6317891B2 JP S6317891 B2 JPS6317891 B2 JP S6317891B2 JP 55024367 A JP55024367 A JP 55024367A JP 2436780 A JP2436780 A JP 2436780A JP S6317891 B2 JPS6317891 B2 JP S6317891B2
- Authority
- JP
- Japan
- Prior art keywords
- steel strip
- cold rolling
- cold
- rolling
- edges
- 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
Links
- 238000005097 cold rolling Methods 0.000 claims description 23
- 229910000831 Steel Inorganic materials 0.000 claims description 20
- 239000010959 steel Substances 0.000 claims description 20
- 229910000677 High-carbon steel Inorganic materials 0.000 claims description 9
- 229910001562 pearlite Inorganic materials 0.000 claims description 8
- FBPFZTCFMRRESA-JGWLITMVSA-N D-glucitol Chemical group OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-JGWLITMVSA-N 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 238000005098 hot rolling Methods 0.000 claims description 5
- 229910052799 carbon Inorganic materials 0.000 claims description 3
- 239000010960 cold rolled steel Substances 0.000 claims description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 description 9
- 239000000463 material Substances 0.000 description 9
- 238000005336 cracking Methods 0.000 description 7
- 238000005096 rolling process Methods 0.000 description 5
- 238000009966 trimming Methods 0.000 description 4
- 229910000963 austenitic stainless steel Inorganic materials 0.000 description 3
- 210000005069 ears Anatomy 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000007423 decrease Effects 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 238000004093 laser heating Methods 0.000 description 2
- 238000005496 tempering Methods 0.000 description 2
- 238000005275 alloying Methods 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 238000003303 reheating Methods 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
Landscapes
- Metal Rolling (AREA)
- Heat Treatment Of Sheet Steel (AREA)
- Heat Treatment Of Articles (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Description
本発明は、パテンテイング処理を伴うバネ材等
の高強度鋼帯の製造法に関する。
例えば自動車の安全ベルトに装着されるリトラ
クターバネの如きバネの材料には、従来、オース
テナイト系ステンレス鋼（例えばSUS301など）
をテンパーロールによつてエキストラーハード
（JISG4313調質記号EH）に調質した極薄材（例
えば0.3mm以下）が使用されている。このオース
テナイト系ステンレス鋼のバネ材は、Ni、Cr系
の高価な合金元素を多量に含有するので高価とな
るという経済面の欠点がある。このため、安価な
高炭素鋼系の材料を使用し、圧延によつてバネに
要求される強度を付与して板バネが製造できれば
極めて有利である。
この高炭素鋼の鋼帯にバネに要求される強度を
付与する方法の１つに、線材の場合と同様に、鋼
帯をパテンテイング処理し、これに80〜95％の冷
間加工を与える処法が考えられる。だが、冷間圧
延によつてこの高い加工率を付与すると、パテン
テイング処理した高炭素鋼はその塑性変形能が小
さいので、鋼帯の耳割れが発生し、破断の危険を
伴つて、実作業の安全面に問題が生ずる。しか
も、この耳割れ、破断によつて歩留りが低下して
製造コストの上昇を招くことになり、この高炭素
鋼系への切換えの主眼である経済的メリツトも失
う結果となる。
本発明は、この耳割れ発生による安全面での問
題と歩留低下の問題を解決することを目的として
なされた高強度鋼帯の製造法を提供するものであ
り、熱間圧延後の冷却制御またはパテンテイング
処理によつて微細パーライト組織またはソルバイ
ト組織を有する炭素含有量0.50％以上の高炭素鋼
の熱延鋼帯を製造し、この熱延鋼帯を冷間圧延し
て繊維状組織の発達した高強度冷延鋼帯を製造す
るにさいし、冷間圧延の途中において、耳部のみ
を最高到達温度800〜950℃の温度に加熱して該耳
部のみを再び微細パーライト組織またはソルバイ
ト組織に戻す局部パテンテイング処理を行ない、
次いで冷間圧延を続行することを特徴とするもの
である。
以下に本発明の詳細を実施例と共に説明する。
先にも例示したリトラクターバネは、幅が10mm
以下の細いゼンマイ形であり、その使用上の特性
は線材に近似している。このようなゼンマイ板を
得るには、線材の場合と同様にその鋼の組織の観
点から言えば、熱間圧延後の冷却制御または鋼帯
のパテンテイング処理によつて微細パーライト組
織またはソルバイト組織とし、以後の冷間圧延に
よつて層状炭化物を圧延方向に展伸させ、積極的
に繊維状組織を形成させるのがよい。しかし、こ
の熱間圧延後の冷却制御またはパテンテイング処
理した高炭素鋼帯（100Kg／mm2前後の強度を有す
る）は、冷間圧延条件を種々変更しても冷間圧延
率55％前後で耳部にクラツクが入り、以後の冷間
圧延は実操業上不可能となる。これを第１表に示
す。第１表は、100Kg／mm2前後の強度を有する冷
却制御した高炭素熱延鋼帯およびパテンテイング
鋼帯の耳割れ発生に到るまでの冷間圧延率を示し
たものである。
The present invention relates to a method for manufacturing high-strength steel strips such as spring materials that involves patenting treatment. For example, the material of springs such as retractor springs attached to automobile safety belts has conventionally been made of austenitic stainless steel (such as SUS301).
Ultra-thin material (for example, 0.3 mm or less) that has been tempered to extra hard (JISG4313 tempering symbol EH) using a temper roll is used. This austenitic stainless steel spring material has an economic disadvantage in that it is expensive because it contains a large amount of Ni and Cr-based expensive alloying elements. For this reason, it would be extremely advantageous if a plate spring could be manufactured using an inexpensive high-carbon steel material and imparting the required strength to the spring through rolling. One way to give this high carbon steel strip the strength required for springs is to patent the steel strip and subject it to 80 to 95% cold working, similar to the case with wire rods. Law is considered. However, when this high processing rate is applied through cold rolling, the patented high carbon steel has a small plastic deformability, so edge cracking occurs in the steel strip, which poses a risk of breakage, making it difficult to perform actual work. Safety issues arise. Furthermore, the cracking and breakage of the edges lower the yield and increase the manufacturing cost, which also results in the loss of the economic merit that is the main purpose of switching to high carbon steel. The present invention provides a method for manufacturing a high-strength steel strip, which is aimed at solving the safety problems and yield reduction problems caused by the occurrence of edge cracks. Alternatively, a hot-rolled steel strip of high carbon steel having a carbon content of 0.50% or more and having a fine pearlite structure or a sorbite structure is produced by a patenting process, and this hot-rolled steel strip is cold-rolled to have a developed fibrous structure. When manufacturing high-strength cold-rolled steel strips, only the edges are heated to a maximum temperature of 800 to 950°C during cold rolling to return only the edges to a fine pearlite or sorbite structure. Perform local patenting treatment,
This is characterized in that cold rolling is then continued. The details of the present invention will be explained below along with examples. The retractor spring shown earlier has a width of 10 mm.
It has a thin spiral shape as shown below, and its usage characteristics are similar to wire rods. In order to obtain such a spiral plate, from the viewpoint of the structure of the steel, as in the case of wire rods, it is necessary to create a fine pearlite structure or sorbite structure by controlling cooling after hot rolling or by patenting the steel strip, It is preferable that the layered carbide be expanded in the rolling direction by the subsequent cold rolling to actively form a fibrous structure. However, this high carbon steel strip (having a strength of around 100Kg/ mm2 ) that has undergone cooling control or patenting treatment after hot rolling has a cold rolling rate of around 55% even after various changes in cold rolling conditions. A crack appears in the part, making subsequent cold rolling impossible in actual operation. This is shown in Table 1. Table 1 shows the cold rolling rate until edge cracking occurs for cooling-controlled high-carbon hot-rolled steel strips and patented steel strips having a strength of around 100 Kg/mm 2 .
【表】
したがつて、このような微細パーライト組織ま
たはソルバイト組織の鋼帯に80〜95％の冷間圧延
を施して、所望のバネ材強度を得ようとしても無
理がかかり、あえて行なうならば、耳割れ部をト
リミングしながら圧延回数を重ねるしかないが、
この場合には、トリミングによるバリ発生を伴う
し、また３〜４回ものトリミングを行なえば、著
しい歩留の低下、作業員の増大、仕掛り日数の増
大に伴う発錆、等の生産性および品質面で実操業
上許容できない問題に当面することになる。しか
も、これによつても、最大圧延率（トータル冷延
率）が80％に満たないところで終止しなければ安
全面で問題となるであろう。
これに対処すべく、本発明者らは、トリミング
された耳部の研磨仕上げ、耳部の焼なまし等を検
討し、その試験をくり返したが、良好な結果は得
られなかつた。ところが、この冷間圧延の途中で
耳部のみを最高到達温度800〜950℃に加熱する局
部パテンパテイグを実施すると、この問題は一挙
に解決することがわかつた。この局部パテンテイ
ングの加熱は、ライン内でのレーザー加熱、高周
波誘導加熱もしくはガス火炎加熱のいづれによつ
ても好適に実施できる。
第１図は、熱間圧延後の冷却制御により、硬さ
がHRC31の微細パーライト組織とした板厚2.70
mmのSAE1070熱延帯鋼に50％の冷間圧延した
（板厚1.35mmｔ）のち、両耳部５mmを種々の温度
に再加熱したときの硬さ変化を示したものであ
る。ここでいう再加熱温度とは連続的に搬送され
る鋼帯の最高到達温度であり、保持時間は特に取
つていない。加熱温度による耳部の硬さは710℃
で最も軟化し、800℃以上では初期パテンテイン
グ硬さに近いHRC29.5〜30.5に再硬化している。
熱影響による軟化域はレーザー加熱、高周波誘導
加熱、ガス火炎加熱等の熱源の種類によつて異な
るが、最大でも２mm以内にとどまつていることが
確認された。
第２図は、第１図に示すごとく耳部を局部加熱
した鋼帯を再び冷間圧延し、耳割れを生ずること
なしに到達できた冷間圧延率を示したものであ
る。第２図より明らかなように、耳割れは炭化物
が微細に球状化して最も軟化する710℃加熱より
も、800℃以上に加熱した再パテンテイング処理
の方が耳割れは発生し難く、70％以上（トータル
冷延率85％）の冷間圧延に耐えられることがわか
る。再パテンテイング後の耳割れ発生冷延率が、
第２図に示すごとく70％以上となるのは板厚が薄
くなることによる効果と考えられる。またトリミ
ング代（しろ）内の耳割れを許容すれば80％（ト
ータル冷延率90％）までの冷間圧延は可能であ
る。
以上のとおり、本処理方法によれば冷間圧延途
上耳部のみ再パテンテイング処理を１回行えばよ
いので製造工程の合理化とともに材料歩留も著し
く改善されることが明らかである。
なお、再パテンテイング温度が950℃を越える
とオーステナイト粒度が粗大化し、一部にマルテ
ンサイト、トルースタイト等の過冷組織が生じ、
再び耳割れ発生冷延率が低下するため再パテンテ
イング温度は800〜950℃とする必要がある。ま
た、本発明に適用する高炭素鋼は、Ｃ含有量が
0.50〜0.90％、Mn含有量が0.90％以下のものであ
るのが望ましい。
本発明によると、従来オーステナイト系ステン
レス鋼によつて製造されていたリトラクター・バ
ネ等を高炭素鋼によつて製造することが可能とな
り、その製品単価の低減に大きく貢献するが、本
発明による高強度冷延鋼帯は、従来焼入れ焼戻し
処理で製造されていた通常の特殊鋼薄板バネある
いはゼンマイ等にも代替可能であり、バネ材分野
に新材料を提供するものである。[Table] Therefore, it would be difficult to obtain the desired spring material strength by subjecting a steel strip with such a fine pearlite structure or sorbite structure to 80 to 95% cold rolling, and if you dare to do so, However, the only option is to repeat the rolling process while trimming the cracked edges.
In this case, burrs are generated due to trimming, and if trimming is performed as many as 3 or 4 times, productivity decreases significantly, the number of workers increases, and rust occurs due to an increase in the number of work in progress. In terms of quality, we will be faced with problems that are unacceptable in actual operation. Moreover, even with this, there will be a safety problem unless the rolling process is stopped when the maximum rolling ratio (total cold rolling ratio) is less than 80%. In order to deal with this, the present inventors considered polishing the trimmed ears, annealing the ears, etc., and repeated the tests, but no good results were obtained. However, it has been found that this problem can be solved at once by performing local patting, which heats only the edges to a maximum temperature of 800 to 950°C during cold rolling. This heating for local patenting can be suitably carried out by in-line laser heating, high frequency induction heating, or gas flame heating. Figure 1 shows a sheet with a thickness of 2.70 and a fine pearlite structure with a hardness of HRC31 created by cooling control after hot rolling.
This figure shows the change in hardness when 5 mm of both ears were reheated to various temperatures after 50% cold rolling (sheet thickness: 1.35 mm) of SAE 1070 hot rolled steel strip. The reheating temperature referred to here is the highest temperature reached by the continuously conveyed steel strip, and no particular holding time is set. The hardness of the ear part due to heating temperature is 710℃
It softens the most at temperatures above 800℃, and rehardens to H R C29.5 to 30.5, which is close to the initial patenting hardness.
The softening range due to thermal effects differs depending on the type of heat source such as laser heating, high-frequency induction heating, gas flame heating, etc., but it was confirmed that the softening range remained within 2 mm at most. FIG. 2 shows the cold rolling rate achieved without causing edge cracks when the steel strip whose edges were locally heated as shown in FIG. 1 was cold rolled again. As is clear from Figure 2, edge cracking is less likely to occur when repatenting is heated to 800°C or higher, and is more than 70% more likely to occur when heated to 800°C or higher than when heated to 710°C, where the carbide becomes finely spheroidized and softens the most. It can be seen that it can withstand cold rolling (total cold rolling rate of 85%). The cold rolling rate at which edge cracking occurs after repatenting is
As shown in Figure 2, the reason why it is more than 70% is thought to be due to the thinner plate thickness. Furthermore, if edge cracking within the trimming margin is allowed, cold rolling up to 80% (total cold rolling ratio of 90%) is possible. As described above, it is clear that according to the present processing method, only the cold-rolled edge portion needs to be re-patented once, thereby streamlining the manufacturing process and significantly improving the material yield. Note that when the repatenting temperature exceeds 950℃, the austenite grain size becomes coarser, and supercooled structures such as martensite and troostite are formed in some parts.
Since edge cracking occurs again and the cold rolling rate decreases, the repatenting temperature needs to be 800 to 950°C. Furthermore, the high carbon steel applied to the present invention has a C content of
It is preferable that the Mn content is 0.50 to 0.90% and 0.90% or less. According to the present invention, retractors, springs, etc., which were conventionally manufactured using austenitic stainless steel, can be manufactured using high carbon steel, which greatly contributes to reducing the unit price of the product. The high-strength cold-rolled steel strip can also be used as a substitute for ordinary special steel thin plate springs or mainsprings, which were conventionally manufactured by quenching and tempering, and provides a new material in the field of spring materials.
第１図は、熱間圧延後の冷却制御により微細パ
ーライト組織とした板厚2.70mmのSAE1070熱延帯
鋼に50％の冷間圧延を施したのち、両耳部５mmを
種々の温度に再加熱したときの加熱温度と硬さ変
化の関係図、第２図は、第１図に示すごとく耳部
を局部加熱した鋼帯を再び冷間圧延し、耳割れを
生ずることなしに到達できた冷間圧延率とその局
部加熱温度との関係図である。
Figure 1 shows a 2.70 mm thick SAE1070 hot-rolled steel strip with a fine pearlite structure created by cooling control after hot rolling. After 50% cold rolling, 5 mm of both edges were reheated to various temperatures. Figure 2 shows the relationship between the heating temperature and hardness change during heating.The steel strip whose edges were locally heated as shown in Figure 1 was cold-rolled again without causing edge cracks. FIG. 3 is a diagram showing the relationship between cold rolling reduction and local heating temperature.
Claims (1)
処理によつて微細パーライト組織またはソルバイ
ト組織を有する炭素含有量0.50％以上の高炭素鋼
の熱延鋼帯を製造し、この熱延鋼帯を冷間圧延し
て繊維状組織の発達した高強度冷延鋼帯を製造す
るにさいし、冷間圧延の途中において、耳部のみ
を最高到達温度800〜950℃の温度に加熱して該耳
部のみを再び微細パーライト組織またはソルバイ
ト組織に戻す局部パテンテイング処理を行ない、
次いで冷間圧延を続行することを特徴とする高強
度鋼帯の製造法。1. A hot rolled steel strip of high carbon steel with a carbon content of 0.50% or more and having a fine pearlite structure or a sorbite structure is produced by cooling control or patenting treatment after hot rolling, and this hot rolled steel strip is cold rolled. In order to produce a high-strength cold-rolled steel strip with a developed fibrous structure, only the edges are heated to a maximum temperature of 800 to 950°C during cold rolling, and only the edges are heated again. Performs local patenting treatment to return to fine pearlite or sorbite structure,
A method for producing a high-strength steel strip, characterized in that cold rolling is then continued.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2436780A JPS56119739A (en) | 1980-02-28 | 1980-02-28 | Manufacture of high-strength steel strip |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2436780A JPS56119739A (en) | 1980-02-28 | 1980-02-28 | Manufacture of high-strength steel strip |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56119739A JPS56119739A (en) | 1981-09-19 |
| JPS6317891B2 true JPS6317891B2 (en) | 1988-04-15 |
Family
ID=12136213
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2436780A Granted JPS56119739A (en) | 1980-02-28 | 1980-02-28 | Manufacture of high-strength steel strip |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56119739A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61143572A (en) * | 1985-11-22 | 1986-07-01 | Hitachi Ltd | Manufacture of zirconium alloy |
| KR20020054532A (en) * | 2000-12-28 | 2002-07-08 | 이계안 | A processing method of bumper beam for automobile |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5147423A (en) * | 1974-09-30 | 1976-04-23 | Gen Electric |
-
1980
- 1980-02-28 JP JP2436780A patent/JPS56119739A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5147423A (en) * | 1974-09-30 | 1976-04-23 | Gen Electric |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56119739A (en) | 1981-09-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101755063A (en) | Be used for the steel band that has different thickness at length direction is carried out the annealed method | |
| JPH0112816B2 (en) | ||
| US2731403A (en) | Manufacture of nickel-plated steel | |
| US3904446A (en) | Process of making high strength cold rolled steel having excellent bake-hardening properties | |
| JPS61207521A (en) | Production of steel strip having composite stucture | |
| JPH08302428A (en) | Production of high strength steel strip for spring | |
| JPS6317891B2 (en) | ||
| JP3266902B2 (en) | Manufacturing method of high carbon cold rolled steel strip | |
| JPH059588A (en) | Production of high carbon steel sheet excellent in formability | |
| JPH10204540A (en) | Production of cold rolled high-carbon steel strip | |
| US5451276A (en) | Process for producing a ski edge | |
| JPH0394017A (en) | Production of high strength sheet metal excellent in local elongation | |
| WO2020158017A1 (en) | Carbon alloy steel sheet and method for producing carbon alloy steel sheet | |
| JP2745823B2 (en) | Manufacturing method of as-roll type ultra-high tensile ERW steel pipe for vehicle door impact bar excellent in flattening test characteristics | |
| JPH0116887B2 (en) | ||
| US3250648A (en) | Method of producing hardened steel products | |
| JPS5839737A (en) | Manufacture of high tensile wire rod | |
| US2781283A (en) | Method of processing stainless steels | |
| JP2845020B2 (en) | Manufacturing method of as-roll type ultra-high tensile electric resistance welded steel pipe | |
| JP2927166B2 (en) | Manufacturing method of high carbon cold rolled steel sheet with excellent short-time hardenability | |
| JP7052116B1 (en) | Molding method | |
| JPH01168813A (en) | Manufacture of high-strength hot-rolled thin steel sheet having excellent press workability | |
| JP2792896B2 (en) | Method for producing carbon steel or alloy steel sheet having fine spheroidized carbide | |
| JPH036351A (en) | High fatigue strength spring steel and its manufacture | |
| JPS6259167B2 (en) |