JPH04254532A - Manufacture of galvannealed steel sheet having excellent workability - Google Patents
Manufacture of galvannealed steel sheet having excellent workabilityInfo
- Publication number
- JPH04254532A JPH04254532A JP3136091A JP3136091A JPH04254532A JP H04254532 A JPH04254532 A JP H04254532A JP 3136091 A JP3136091 A JP 3136091A JP 3136091 A JP3136091 A JP 3136091A JP H04254532 A JPH04254532 A JP H04254532A
- Authority
- JP
- Japan
- Prior art keywords
- oxide film
- zone
- furnace
- iron oxide
- film thickness
- 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.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 33
- 239000010959 steel Substances 0.000 title claims abstract description 33
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 14
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims abstract description 30
- 238000010438 heat treatment Methods 0.000 claims abstract description 29
- 238000000137 annealing Methods 0.000 claims abstract description 27
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 5
- 239000001257 hydrogen Substances 0.000 claims abstract description 5
- 238000002485 combustion reaction Methods 0.000 claims abstract description 4
- 238000000034 method Methods 0.000 claims description 18
- 229910001335 Galvanized steel Inorganic materials 0.000 claims description 13
- 239000008397 galvanized steel Substances 0.000 claims description 13
- 230000003647 oxidation Effects 0.000 claims description 9
- 238000007254 oxidation reaction Methods 0.000 claims description 9
- 239000011701 zinc Substances 0.000 abstract description 11
- 238000005275 alloying Methods 0.000 abstract description 10
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 abstract description 7
- 229910052725 zinc Inorganic materials 0.000 abstract description 7
- 238000002791 soaking Methods 0.000 abstract description 3
- 239000010960 cold rolled steel Substances 0.000 abstract description 2
- 238000001816 cooling Methods 0.000 abstract description 2
- 238000010583 slow cooling Methods 0.000 abstract description 2
- 230000001590 oxidative effect Effects 0.000 abstract 1
- 238000000227 grinding Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 238000005246 galvanizing Methods 0.000 description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 238000007747 plating Methods 0.000 description 4
- 239000010953 base metal Substances 0.000 description 3
- 229910000765 intermetallic Inorganic materials 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- 230000004913 activation Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000033116 oxidation-reduction process Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 210000004894 snout Anatomy 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
Landscapes
- Heat Treatment Of Sheet Steel (AREA)
- Control Of Heat Treatment Processes (AREA)
- Coating With Molten Metal (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、合金化溶融亜鉛メッキ
鋼板の製造方法に係り、特に合金化溶融亜鉛メッキ鋼板
として具備すべき加工性を効率的に得られるようにした
ものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an alloyed hot-dip galvanized steel sheet, and particularly to a method for efficiently obtaining the workability that an alloyed hot-dip galvanized steel sheet should have.
【０００２】0002
【従来の技術】近年、自動車鋼板として用いられる冷延
鋼板には、車体の軽量化及び安全性の向上、並びに耐食
性の見地から、プレス加工性に優れることのほかに、高
強度であり、かつ耐食性が要求され、供給鋼材の表面処
理化が強く要求される状況にある。このなかで、最近で
は、特に、 防錆力向上を主目的とした表面処理方法と
しては、生産性の観点から容易に厚メッキ化が可能なゼ
ンジマ−式溶融亜鉛メッキ法がある。このゼンジマ−式
溶融亜鉛メッキ法の場合、弱酸化帯で生成されたＦｅ酸
化膜が、それ以降の還元帯で還元された後、亜鉛浴に浸
漬され、その後、合金化炉に入り、再加熱され、Ｆｅ−
Ｚｎ相互拡散により合金化するが、加熱帯で生成される
Ｆｅ酸化膜が多ければ、多いほど、還元後の表面性状は
、多孔質（ｐｏｒｏｕｓ）状に成り、浴中での反応が促
進され、加工性を阻害する。それは、地鉄界面に生成す
る非常に脆いＦｅ−Ｚｎ金属間化合物が過剰に成長する
ためである。[Prior Art] In recent years, cold-rolled steel sheets used as automobile steel sheets have not only excellent press workability but also high strength and Corrosion resistance is required, and there is a strong demand for surface treatment of supplied steel materials. Among these, recently, a Sendzimer hot-dip galvanizing method, which allows for easy thick plating from the viewpoint of productivity, has been used as a surface treatment method with the main purpose of improving rust prevention ability. In the case of this Sendzimer hot-dip galvanizing method, the Fe oxide film generated in the weak oxidation zone is reduced in the subsequent reduction zone, then immersed in a zinc bath, then entered into an alloying furnace and reheated. and Fe-
Zn is alloyed by interdiffusion, and the more Fe oxide films are produced in the heating zone, the more porous the surface becomes after reduction, and the reaction in the bath is accelerated. Impairs processability. This is because a very brittle Fe-Zn intermetallic compound generated at the interface of the base metal grows excessively.
【０００３】これを抑制するための従来の方法として、
焼鈍炉を完全に間接加熱方式が採用されている。この間
接加熱方式は、炉内が全領域にわたって、還元雰囲気で
あるので、酸化膜が全く生成されず、板厚の緻密な１０
０Å程度の酸化膜が還元されるだけであるので、加工性
を阻害する地鉄界面に生成する非常に脆いＦｅ−Ｚｎ金
属間化合物が過剰に成長せず、加工性の良好な合金化溶
融亜鉛メッキ鋼板を製造することができる。[0003] As a conventional method for suppressing this,
The annealing furnace uses a completely indirect heating method. In this indirect heating method, the entire area inside the furnace is in a reducing atmosphere, so no oxide film is formed, and the dense
Since only an oxide film of about 0 Å is reduced, the extremely brittle Fe-Zn intermetallic compound that forms at the interface of the base metal, which inhibits workability, does not grow excessively, making alloyed molten zinc with good workability. It is possible to produce plated steel sheets.
【０００４】0004
【発明が解決しようとする課題】しかしながら、この方
式では、高Ｓｉ、Ｐ鋼板の高温焼鈍を行なう場合、これ
らの鋼中元素が焼鈍過程中に表面に濃化し、酸化皮膜を
形成し、この酸化膜が局所的な不メッキ、メッキ密着性
不良、もしくは合金ムラを発生させる。 このため、こ
の間接加熱方式は、汎用的な溶融亜鉛メッキ設備として
は、 適していない。そこで、本発明は、高生産性のラ
インにあって、 従来とは異なる方法により、良好な加
工性を有する合金化溶融亜鉛メッキ鋼板を得るためのも
のである。[Problems to be Solved by the Invention] However, in this method, when high-Si, P steel sheets are annealed at high temperatures, these elements in the steel concentrate on the surface during the annealing process, forming an oxide film, and this oxidation The film causes local non-plating, poor plating adhesion, or uneven alloying. Therefore, this indirect heating method is not suitable for general-purpose hot-dip galvanizing equipment. Therefore, the present invention is intended to obtain an alloyed hot-dip galvanized steel sheet having good workability on a high-productivity line by a method different from the conventional method.
【０００５】[0005]
【課題を解決するための手段】上述した問題点を解決し
、その目的を達成するために、本発明の要旨とするとこ
ろは、（１）合金化溶融亜鉛めっき鋼板の製造方法とし
て、焼鈍炉の加熱帯での生成鉄酸化膜、および、還元帯
での鉄酸化膜還元能力をヒ−トサイクル・ラインスピ−
ド・還元帯水素濃度・酸化帯燃焼空気比を用いて計算し
、酸化膜厚（Å）≦２００Åとなるように、焼鈍条件を
制御することを特徴とする加工性の優れた合金化溶融亜
鉛めっき鋼板の製造方法。
（２）合金化溶融亜鉛めっき鋼板の製造方法として、焼
鈍炉の加熱帯での生成鉄酸化膜を実測し、酸化膜厚（Å
）≦２００Åとなるように、焼鈍条件を制御することを
特徴とする加工性の優れた合金化溶融亜鉛めっき鋼板の
製造方法にある。[Means for Solving the Problems] In order to solve the above-mentioned problems and achieve the objectives, the gist of the present invention is (1) to provide an annealing furnace as a method for manufacturing alloyed hot-dip galvanized steel sheets. The iron oxide film formed in the heating zone and the ability to reduce the iron oxide film in the reduction zone are evaluated by heat cycle line speed.
Alloyed molten zinc with excellent workability, characterized by controlling the annealing conditions so that the oxide film thickness (Å)≦200 Å, calculated using the hydrogen concentration in the reduction zone and the combustion air ratio in the oxidation zone. Method of manufacturing plated steel sheets. (2) As a manufacturing method for alloyed hot-dip galvanized steel sheets, the iron oxide film formed in the heating zone of the annealing furnace was actually measured, and the oxide film thickness (Å
)≦200 Å, the method of manufacturing an alloyed hot-dip galvanized steel sheet with excellent workability is characterized by controlling annealing conditions so that the relationship of the present invention is 200 Å.
【０００６】[0006]
【作用】以下、本発明について詳細に説明する。本発明
において、焼鈍炉の加熱帯での生成鉄酸化膜量は、焼鈍
炉の空気比で制御し、ヒ−トサイクルを考慮し計算する
。すなわち酸化膜生成量＝∫（酸化速度）ｄｔで表すこ
とが出来る。
ｍ＜１の場合（ｍは空気比）
酸化速度＝Ａ１・ｅｘｐ（Ｅ１／ＲＴ）・ｍ１ｍ１＝Ｐ
ｃｏ２／Ｐｃｏを近似したもの、ｍ≧１の場合
酸化速度＝Ａ２・ｅｘｐ（Ｅ２／ＲＴ）・ｍ２ｍ２＝Ｐ
ｏ２を近似したもの、
但し、Ａ１、Ａ２は反応定数〔Å／ｓｅｃ〕Ｅは活性化
エネルギ−〔ｃａｌ／ｍｏｌ〕Ｒは１．９８７〔ｃａｌ
／ｍｏｌ・Ｋ〕そして、例えば、ｍ＝０．９０、酸化速
度＝２８００・ｅｘｐ〔−７．８８７／ＲＴ〕
このようにして、酸化速度から生成酸化膜厚を計算する
ことができる。また、還元能力とは、鉄酸化膜厚を還元
帯で還元する能力を言う。そして、この還元能力はヒ−
トサイクル（板温、ライン速度）により算出することが
出来る。すなわち、還元能力＝∫（還元速度）ｄｔで示
すことが出来る。そして、Ｔ≧５７０℃の場合、還元速
度＝７３１・ｅｘｐ（−３２００／ＲＴ）・Ｈ２分圧、
Ｔ＜５７０℃の場合、還元速度＝１．０４×１０６・ｅ
ｘｐ（−１４７００／ＲＴ）Ｈ２分圧の関係がある。こ
れらの関係から、還元速度を求め還元能力を算出するこ
とが出来るものである。これら計算に基づいて、酸化膜
厚（Å）≦２００Åとなるように、焼鈍条件を制御する
か、或いは焼鈍炉の加熱帯での生成鉄酸化膜を実測して
、酸化膜厚（Å）≦２００Åとする。[Operation] The present invention will be explained in detail below. In the present invention, the amount of iron oxide film produced in the heating zone of the annealing furnace is controlled by the air ratio of the annealing furnace, and is calculated taking into account the heat cycle. That is, it can be expressed as oxide film production amount=∫(oxidation rate) dt. When m<1 (m is air ratio) Oxidation rate=A1・exp(E1/RT)・m1m1=P
An approximation of co2/Pco, when m≧1, oxidation rate=A2・exp(E2/RT)・m2m2=P
o2 is approximated, where A1 and A2 are reaction constants [Å/sec] E is activation energy [cal/mol] R is 1.987 [cal
/mol·K] and, for example, m=0.90, oxidation rate=2800·exp [−7.887/RT] In this way, the thickness of the formed oxide film can be calculated from the oxidation rate. Further, the reduction ability refers to the ability to reduce the iron oxide film thickness in a reduction zone. And this reduction ability is
It can be calculated by cycle (plate temperature, line speed). That is, it can be expressed as reduction ability=∫(reduction rate) dt. If T≧570℃, reduction rate = 731・exp(-3200/RT)・H2 partial pressure,
When T<570℃, reduction rate=1.04×106・e
There is a relationship between xp(-14700/RT)H2 partial pressure. From these relationships, the reduction rate can be determined and the reduction ability can be calculated. Based on these calculations, the annealing conditions are controlled so that the oxide film thickness (Å)≦200 Å, or the iron oxide film formed in the heating zone of the annealing furnace is actually measured, and the oxide film thickness (Å)≦ The thickness is set to 200 Å.
【０００７】実測によって制御する場合については、そ
の構成を図１に示す。図１は本発明に係る設備概略図で
あって、冷間圧延後の鋼帯１を予熱炉２で予め加熱した
後、鋼板に対して垂直に火炎を噴射するバ−ナ−を用い
た加熱炉３で鋼帯１の表面生成酸化膜量を１０００Åを
超えない範囲で制御しながら、加熱した後、次の還元帯
である均熱炉４及び焼鈍炉５に入る前に、加熱炉での、
表面生成酸化膜厚量を酸化膜厚計６を用いて実測し、こ
の実測値に基づいて、前記還元能力をヒ−トサイクル、
ラインスピ−ド、還元帯水素濃度を用いて計算し、最適
範囲になるように焼鈍炉５で還元をし、引続き徐冷帯７
および急冷帯８にて、８００〜８２０℃の鋼帯温度を４
５０〜５００℃に急冷する。その後の鋼帯は、 ホット
ブライドル、スナウトを経て、還元雰囲気状態で亜鉛浴
１０に浸漬され、ワイピング装置で付着量が調整され、
５００〜５２０℃の温度に合金化加熱炉１２で加熱され
合金化溶融亜鉛めっき鋼板が得られる。[0007] In the case of control based on actual measurements, the configuration is shown in FIG. FIG. 1 is a schematic diagram of the equipment according to the present invention, in which a steel strip 1 after cold rolling is preheated in a preheating furnace 2, and then heated using a burner that injects flame perpendicularly to the steel strip. After heating the steel strip 1 in the furnace 3 while controlling the amount of oxide film formed on the surface within a range not exceeding 1000 Å, the steel strip 1 is heated in the heating furnace before entering the soaking furnace 4 and annealing furnace 5, which are the next reduction zones. ,
The thickness of the oxide film formed on the surface is actually measured using an oxide film thickness meter 6, and based on this measured value, the reduction ability is determined by the heat cycle,
Calculated using the line speed and hydrogen concentration in the reduction zone, reduction is performed in the annealing furnace 5 to the optimum range, and then in the slow cooling zone 7.
and quenching zone 8, the steel strip temperature is 800-820℃.
Rapidly cool to 50-500°C. After that, the steel strip passes through a hot bridle and a snout, and is immersed in a zinc bath 10 in a reducing atmosphere, and the amount of adhesion is adjusted using a wiping device.
It is heated in an alloying heating furnace 12 to a temperature of 500 to 520°C to obtain an alloyed hot-dip galvanized steel sheet.
【０００８】図２は、本発明の制御システムを示す図で
あって、鋼帯１は、直火加熱炉３の燃焼廃ガスの廃熱を
利用した予熱炉２で予熱された後、直火加熱炉３で最高
約７００℃まで鋼帯表面を加熱し、その場合に鋼板に対
して垂直に火炎を噴射するバ−ナ−１１を千鳥状に配設
し、酸化膜量を最大１０００Åを超えない範囲で急速加
熱する。その結果を酸化膜厚計６からの指令に基づき、
目標酸化膜比較演算機によって、酸化膜厚検出値と別に
設定した目標値とを比較し、その差信号によって、直火
加熱炉をフイ−ドバック制御する。一方、設定された酸
化膜厚目標値は、還元指令装置に指示され、還元帯であ
る焼鈍炉５に指令され、酸化膜厚を最大２００Å以下に
保持するように制御する。この結果を還元帯出側酸化膜
厚計によって再確認し、もし仮に、目標酸化膜厚を超え
る場合には、還元指令装置を介して焼鈍炉における還元
能力をフイ−ドバック制御することによって、最適目標
の酸化膜厚の状態で徐冷、急冷して、亜鉛浴１０に浸漬
され、合金化加熱炉１２で加熱されて合金化する。FIG. 2 is a diagram showing the control system of the present invention, in which the steel strip 1 is preheated in a preheating furnace 2 that utilizes the waste heat of combustion waste gas from a direct-fired heating furnace 3, and then heated in a direct-fired heating furnace 3. The surface of the steel strip is heated to a maximum of about 700°C in the heating furnace 3, and burners 11 are arranged in a staggered manner to inject flames perpendicularly to the steel plate, thereby increasing the amount of oxide film to a maximum of 1000 Å. Heat rapidly within the range. Based on the command from the oxide film thickness meter 6, the results are
A target oxide film comparison calculator compares the detected oxide film thickness with a separately set target value, and the direct fire heating furnace is feedback-controlled based on the difference signal. On the other hand, the set oxide film thickness target value is instructed to the reduction command device, and is directed to the annealing furnace 5, which is a reduction zone, to control the oxide film thickness to be maintained at a maximum of 200 Å or less. This result is reconfirmed using a reduction zone exit side oxide film thickness meter, and if the target oxide film thickness is exceeded, the reduction capacity in the annealing furnace is feedback-controlled via a reduction command device to reach the optimal target. It is slowly cooled and rapidly cooled in a state where the oxide film has a thickness of , immersed in a zinc bath 10, and heated in an alloying heating furnace 12 to be alloyed.
【０００９】以上のように計算及び、実測に基づく生成
酸化膜制御を行うものであるが、その生成酸化膜厚を常
に２００Å以下に制御する必要がある。この生成酸化膜
厚を２００Å以下に抑える理由について、図３に示す。
図３はパウダリング性（加工性）と生成酸化膜厚との関
係を示した図である。また、パウダリング性については
、メッキ付着量３５ｇ／ｍ２合金化溶融亜鉛メッキした
鋼板を６０°Ｖ曲げしたときの剥離幅をｍｍで表したも
のである。このパウダリング性を２ｍｍ以下に抑えるた
めには、生成酸化膜厚を２００Å以下に抑える必要があ
る。しかも、２００Åを超えると急激にパウダリング性
が悪くなることがわかる。これからも、生成酸化膜厚を
２００Å以下に抑える必要がある。Although the generated oxide film is controlled based on calculations and actual measurements as described above, it is necessary to always control the thickness of the generated oxide film to 200 Å or less. The reason why the thickness of the generated oxide film is suppressed to 200 Å or less is shown in FIG. FIG. 3 is a diagram showing the relationship between powdering property (workability) and the thickness of the produced oxide film. Further, powdering property is expressed in mm as the peeling width when a steel plate coated with galvanized alloy with a coating weight of 35 g/m2 is bent by 60°V. In order to suppress this powdering property to 2 mm or less, it is necessary to suppress the thickness of the generated oxide film to 200 Å or less. Furthermore, it can be seen that powdering properties deteriorate rapidly when the thickness exceeds 200 Å. It is necessary to continue to suppress the thickness of the generated oxide film to 200 Å or less.
【００１０】0010
【実施例】実施例１
Ｃ ０．００２５、Ｓｉ ０．０２、Ｍｎ ０．
１０、Ｐ ０．００１０、Ｎ１８ｐｐｍ、Ｓ ０．
０００８、ＡＩ ０．００２６、Ｃｒ ０．００１
２、Ｃａ１８ｐｐｍ、残部Ｆｅから成る鋼成分を有する
高Ｓｉ含有ＳＵＬＣ系鋼を、予熱炉にて約３５０℃に加
熱し、その後、垂直に火炎を噴射する直火加熱炉にて約
７３０℃まで加熱する。この場合の空気比０．８、ライ
ンスピ−ド１００ｍｐｍとし、還元帯水素濃度１５％で
の焼鈍炉からの出側板温は８５０℃に加熱された。この
ときの加熱帯での生成酸化膜と還元帯での鉄酸化還元能
力から、生成酸化膜演算機にて計算した結果は１５０Å
であった。この酸化膜厚の状態で、５００℃に急冷され
、４６０℃の溶融亜鉛めっき浴温に浸漬させ、エア−ワ
イピングでめっき量を３５ｇ／ｍ２とした。その後５１
０℃に合金化加熱をして合金化処理した。その結果、パ
ウダリング性（６０°Ｖ曲げ剥離幅）は１．９であった
。[Example] Example 1 C 0.0025, Si 0.02, Mn 0.
10, P 0.0010, N18ppm, S 0.
0008, AI 0.0026, Cr 0.001
2. A high-Si content SULC steel with a steel composition of 18 ppm Ca and the balance Fe is heated to approximately 350°C in a preheating furnace, and then heated to approximately 730°C in a direct-fired heating furnace that injects flame vertically. do. In this case, the air ratio was 0.8, the line speed was 100 mpm, the hydrogen concentration in the reduction zone was 15%, and the plate temperature at the outlet from the annealing furnace was heated to 850°C. At this time, from the oxide film produced in the heating zone and the iron oxidation-reduction ability in the reduction zone, the result calculated by the oxide film calculator was 150 Å.
Met. In this state of oxide film thickness, it was rapidly cooled to 500°C, immersed in a hot-dip galvanizing bath temperature of 460°C, and air-wiped to a plating amount of 35 g/m2. then 51
Alloying treatment was carried out by heating to 0°C. As a result, the powdering property (60° V bend peeling width) was 1.9.
【００１１】実施例２
Ｃ ０．００２５、Ｓｉ ０．０２、Ｍｎ ０．
１０、Ｐ ０．００１０、Ｎ１８ｐｐｍ、Ｓ ０．
００１０、ＡＩ ０．００２０、Ｔｉ ０．０５０
、Ｎｂ０．０１０、残部Ｆｅから成る鋼成分を有する、
Ｔｉ−Ｎｂ−ＳＵＬＣ系鋼を、予熱炉にて約３５０℃
に加熱し、その後、垂直に火炎を噴射する直火加熱炉に
て約７４０℃まで加熱する。この加熱された鋼帯を酸化
膜厚計にて生成酸化膜を実測し、この実測値が目標酸化
膜比較演算機に送られ、その検出値と別に設定した目標
値１７０Åを比較し、その差信号によって、もし仮に２
００Åを超す酸化膜厚の場合には、直火加熱炉にフイ−
ドバック制御する。目標酸化膜厚であれば還元指令装置
に送られ、 焼鈍炉にて８６０℃に加熱される。この加
熱された鋼帯は均熱、焼鈍され、徐冷の後５００℃に急
冷され、４６０℃の溶融亜鉛めっき浴温に浸漬され、エ
ア−ワイピングでめっき量を３５ｇ／ｍ２に調節した後
、５１０℃に合金化加熱をして合金化処理した。その結
果、パウダリング性（６０°Ｖ曲げ剥離幅）は１．８で
あった。Example 2 C 0.0025, Si 0.02, Mn 0.
10, P 0.0010, N18ppm, S 0.
0010, AI 0.0020, Ti 0.050
, having a steel composition consisting of Nb0.010 and the balance Fe,
Ti-Nb-SULC steel is heated to approximately 350℃ in a preheating furnace.
Then, it is heated to about 740°C in a direct flame heating furnace that injects flame vertically. The oxide film formed on this heated steel strip is actually measured using an oxide film thickness meter, and this measured value is sent to a target oxide film comparison computer, and the detected value is compared with a separately set target value of 170 Å, and the difference is determined. By the signal, if 2
If the oxide film thickness exceeds 0.00 Å, the direct-fired heating furnace should be heated.
back control. If the target oxide film thickness is met, it is sent to the reduction command device and heated to 860°C in an annealing furnace. This heated steel strip was soaked, annealed, slowly cooled, then rapidly cooled to 500°C, immersed in a hot-dip galvanizing bath temperature of 460°C, and the coating amount was adjusted to 35 g/m2 by air wiping. Alloying treatment was carried out by heating to 510°C. As a result, the powdering property (60° V bend peeling width) was 1.8.
【００１２】0012
【発明の効果】以上述べたように、本発明は、従来と異
なり、高生産性のラインにあって、鉄酸化膜厚と還元能
力との関係から計算、ないし、酸化膜厚計を設けて実測
し、その結果を修正することによって、高Ｓｉ，Ｐ含有
鋼であっても、合金化溶融亜鉛めっき条件をいたずらに
変更することなく、 普通鋼と同様の合金化特性が得ら
れ、加工性を阻害する地鉄界面に生成する非常に脆いＦ
ｅ−Ｚｎ金属間化合物を過剰に成長させることなく、加
工性の極めて良好な溶融亜鉛めっき鋼板を実用上極めて
有利な高効率的、かつ高生産性を可能ならしめた製造方
法にある。[Effects of the Invention] As described above, the present invention differs from the conventional art in that it is possible to calculate the relationship between iron oxide film thickness and reducing ability or to install an oxide film thickness meter in a high-productivity line. By actually measuring and correcting the results, even with high Si and P content steel, it is possible to obtain alloying properties similar to ordinary steel without unnecessarily changing the alloying hot-dip galvanizing conditions, and improve workability. Very brittle F generated at the base metal interface that inhibits
The present invention provides a method for manufacturing a hot-dip galvanized steel sheet with extremely good workability without excessively growing an e-Zn intermetallic compound, which is extremely advantageous in practice, with high efficiency and high productivity.
【００１３】[0013]
【図１】本発明に係る設備概略図である。FIG. 1 is a schematic diagram of equipment according to the present invention.
【図２】本発明の制御システムを示す図である。FIG. 2 is a diagram showing a control system of the present invention.
【図３】パウダリング性と生成酸化膜厚との関係を示し
た図である。FIG. 3 is a diagram showing the relationship between powdering property and the thickness of the produced oxide film.
１ 鋼帯、２ 予熱炉、３ 直火加熱炉、４
均熱炉、５ 焼鈍炉、６ 酸化膜厚計、７ 徐冷
帯、８ 急冷帯、９ 還元帯出側酸化膜厚計、１０
亜鉛浴、１１ バ−ナ−、１２ 合金化加熱炉
。1 steel strip, 2 preheating furnace, 3 direct fire heating furnace, 4
Soaking furnace, 5 Annealing furnace, 6 Oxide film thickness gauge, 7 Annealing zone, 8 Rapid cooling zone, 9 Reduction zone exit side oxide film thickness gauge, 10
Zinc bath, 11 burners, 12 alloying furnace.
Claims (3)
として、焼鈍炉の加熱帯での生成鉄酸化膜、および、還
元帯での鉄酸化膜還元能力をヒ−トサイクル・ラインス
ピ−ド・還元帯水素濃度・酸化帯燃焼空気比を用いて計
算し、酸化膜厚（Å）≦２００Åとなるように、焼鈍条
件を制御することを特徴とする加工性の優れた合金化溶
融亜鉛めっき鋼板の製造方法。[Claim 1] As a method for manufacturing alloyed hot-dip galvanized steel sheets, the iron oxide film produced in the heating zone of an annealing furnace and the iron oxide film reduction ability in the reduction zone are reduced by heat cycle, line speed, and reduction. An alloyed hot-dip galvanized steel sheet with excellent workability characterized by controlling the annealing conditions so that the oxide film thickness (Å)≦200 Å, calculated using the hydrogen concentration and oxidation zone combustion air ratio. Production method.
として、焼鈍炉の加熱帯での生成鉄酸化膜を実測し、酸
化膜厚（Å）≦２００Åとなるように、焼鈍条件を制御
することを特徴とする加工性の優れた合金化溶融亜鉛め
っき鋼板の製造方法。[Claim 2] As a method for manufacturing an alloyed hot-dip galvanized steel sheet, the iron oxide film formed in the heating zone of the annealing furnace is actually measured, and the annealing conditions are controlled so that the oxide film thickness (Å)≦200 Å. A method for manufacturing an alloyed hot-dip galvanized steel sheet with excellent workability.
て垂直に火炎を噴射するバ−ナ−を用いて行うことを特
徴とする請求項１、および２記載の加工性の優れた合金
化溶融亜鉛めっき鋼板の製造方法。3. The method according to claim 1, wherein the heating zone of the annealing furnace is heated using a burner that injects flame perpendicularly to the steel plate. Method for manufacturing alloyed hot-dip galvanized steel sheet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3136091A JPH04254532A (en) | 1991-02-01 | 1991-02-01 | Manufacture of galvannealed steel sheet having excellent workability |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3136091A JPH04254532A (en) | 1991-02-01 | 1991-02-01 | Manufacture of galvannealed steel sheet having excellent workability |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04254532A true JPH04254532A (en) | 1992-09-09 |
Family
ID=12329075
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3136091A Pending JPH04254532A (en) | 1991-02-01 | 1991-02-01 | Manufacture of galvannealed steel sheet having excellent workability |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04254532A (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8216695B2 (en) | 2004-12-21 | 2012-07-10 | Kobe Steel, Ltd. | Method and facility for hot dip zinc plating |
| JP2012177142A (en) * | 2011-02-25 | 2012-09-13 | Jfe Steel Corp | Method for producing hot-dip galvanized steel sheet |
| WO2012169653A1 (en) | 2011-06-07 | 2012-12-13 | Ｊｆｅスチール株式会社 | High-strength hot-dipped galvanized steel sheet having excellent plating adhesion, and method for producing same |
| WO2013157146A1 (en) | 2012-04-17 | 2013-10-24 | Ｊｆｅスチール株式会社 | Method for producing alloyed hot-dip galvanized steel sheet having excellent adhesion to plating and excellent sliding properties |
| WO2014136417A1 (en) | 2013-03-05 | 2014-09-12 | Ｊｆｅスチール株式会社 | High-strength hot-dip galvanized steel sheet and process for manufacturing same |
| WO2014188697A1 (en) | 2013-05-21 | 2014-11-27 | Ｊｆｅスチール株式会社 | Method for manufacturing high-strength alloyed hot-dip galvanized steel plate |
| WO2015087549A1 (en) | 2013-12-13 | 2015-06-18 | Ｊｆｅスチール株式会社 | Method for manufacturing high-strength hot-dip galvanized steel sheet |
| CN104870667A (en) * | 2012-10-05 | 2015-08-26 | 琳德股份公司 | Preheating and annealing of cold rolled metal strip |
| KR20170039733A (en) | 2014-09-08 | 2017-04-11 | 제이에프이 스틸 가부시키가이샤 | Method and apparatus for producing high-strength hot-dipped galvanized steel sheet |
| WO2018079124A1 (en) | 2016-10-25 | 2018-05-03 | Ｊｆｅスチール株式会社 | Method for producing high strength hot-dip galvanized steel sheet |
| KR20180111931A (en) | 2016-03-11 | 2018-10-11 | 제이에프이 스틸 가부시키가이샤 | METHOD FOR MANUFACTURING STRENGTH OF HIGH-STRENGTH HOT WATER |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6240320A (en) * | 1985-08-13 | 1987-02-21 | Sumitomo Metal Ind Ltd | Method for measuring thickness of oxide film in continuous annealing furnace |
| JPH02194127A (en) * | 1989-01-23 | 1990-07-31 | Chugai Ro Co Ltd | Method for controlling heating of direct-fired heating zone |
-
1991
- 1991-02-01 JP JP3136091A patent/JPH04254532A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6240320A (en) * | 1985-08-13 | 1987-02-21 | Sumitomo Metal Ind Ltd | Method for measuring thickness of oxide film in continuous annealing furnace |
| JPH02194127A (en) * | 1989-01-23 | 1990-07-31 | Chugai Ro Co Ltd | Method for controlling heating of direct-fired heating zone |
Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8216695B2 (en) | 2004-12-21 | 2012-07-10 | Kobe Steel, Ltd. | Method and facility for hot dip zinc plating |
| JP2012177142A (en) * | 2011-02-25 | 2012-09-13 | Jfe Steel Corp | Method for producing hot-dip galvanized steel sheet |
| US9677163B2 (en) | 2011-06-07 | 2017-06-13 | Jfe Steel Corporation | High strength galvanized steel sheet excellent in terms of coating adhesiveness and method for manufacturing the same |
| WO2012169653A1 (en) | 2011-06-07 | 2012-12-13 | Ｊｆｅスチール株式会社 | High-strength hot-dipped galvanized steel sheet having excellent plating adhesion, and method for producing same |
| WO2013157146A1 (en) | 2012-04-17 | 2013-10-24 | Ｊｆｅスチール株式会社 | Method for producing alloyed hot-dip galvanized steel sheet having excellent adhesion to plating and excellent sliding properties |
| KR20140138245A (en) | 2012-04-17 | 2014-12-03 | 제이에프이 스틸 가부시키가이샤 | Method for producing alloyed hot-dip galvanized steel sheet having excellent adhesion to plating and excellent sliding properties |
| CN104870667A (en) * | 2012-10-05 | 2015-08-26 | 琳德股份公司 | Preheating and annealing of cold rolled metal strip |
| WO2014136417A1 (en) | 2013-03-05 | 2014-09-12 | Ｊｆｅスチール株式会社 | High-strength hot-dip galvanized steel sheet and process for manufacturing same |
| WO2014188697A1 (en) | 2013-05-21 | 2014-11-27 | Ｊｆｅスチール株式会社 | Method for manufacturing high-strength alloyed hot-dip galvanized steel plate |
| US10087500B2 (en) | 2013-05-21 | 2018-10-02 | Jfe Steel Corporation | Method for manufacturing high-strength galvannealed steel sheet |
| KR20150136113A (en) | 2013-05-21 | 2015-12-04 | 제이에프이 스틸 가부시키가이샤 | Method for manufacturing high-strength alloyed hot-dip galvanized steel plate |
| KR20160071423A (en) | 2013-12-13 | 2016-06-21 | 제이에프이 스틸 가부시키가이샤 | Method for manufacturing high-strength hot-dip galvanized steel sheet |
| WO2015087549A1 (en) | 2013-12-13 | 2015-06-18 | Ｊｆｅスチール株式会社 | Method for manufacturing high-strength hot-dip galvanized steel sheet |
| US10138530B2 (en) | 2013-12-13 | 2018-11-27 | Jfe Steel Corporation | Method for producing high-strength galvannealed steel sheets |
| KR20170039733A (en) | 2014-09-08 | 2017-04-11 | 제이에프이 스틸 가부시키가이샤 | Method and apparatus for producing high-strength hot-dipped galvanized steel sheet |
| KR20180111931A (en) | 2016-03-11 | 2018-10-11 | 제이에프이 스틸 가부시키가이샤 | METHOD FOR MANUFACTURING STRENGTH OF HIGH-STRENGTH HOT WATER |
| US10988836B2 (en) | 2016-03-11 | 2021-04-27 | Jfe Steel Corporation | Method for producing high-strength galvanized steel sheet |
| WO2018079124A1 (en) | 2016-10-25 | 2018-05-03 | Ｊｆｅスチール株式会社 | Method for producing high strength hot-dip galvanized steel sheet |
| KR20190057335A (en) | 2016-10-25 | 2019-05-28 | 제이에프이 스틸 가부시키가이샤 | METHOD FOR MANUFACTURING STRENGTH OF HIGH-STRENGTH HOT WATER |
| US11535922B2 (en) | 2016-10-25 | 2022-12-27 | Jfe Steel Corporation | Method for manufacturing high-strength galvanized steel sheet |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6797901B2 (en) | Yield strength 600MPa class High elongation Aluminum Zinc Hot-dip galvanized steel sheet and color-plated steel sheet manufacturing method | |
| JP5720856B2 (en) | Galvanized steel sheet for hot forming | |
| WO2021166350A1 (en) | Method for producing high-strength hot dipped galvanized steel sheet | |
| JP5799819B2 (en) | Method for producing hot-dip galvanized steel sheet with excellent plating wettability and pick-up resistance | |
| EP2659019B1 (en) | Aluminum coated steel sheet having excellent oxidation resistance and heat resistance | |
| JP4912684B2 (en) | High-strength hot-dip galvanized steel sheet, production apparatus therefor, and method for producing high-strength alloyed hot-dip galvanized steel sheet | |
| JPH04254532A (en) | Manufacture of galvannealed steel sheet having excellent workability | |
| US6635313B2 (en) | Method for coating a steel alloy | |
| JP4264373B2 (en) | Method for producing molten Al-based plated steel sheet with few plating defects | |
| JP2970445B2 (en) | Hot-dip galvanizing method for Si-added high tensile steel | |
| JP2530939B2 (en) | Method for manufacturing high-strength hot-dip galvanized steel sheet containing high Si | |
| US6902829B2 (en) | Coated steel alloy product | |
| JP2513532B2 (en) | Method for producing high-strength hot-dip galvanized steel sheet of high Si content steel | |
| JPH04254531A (en) | Method for annealing high si-containing high tensile strength steel before galvanizing | |
| JP2964911B2 (en) | Alloying hot-dip galvanizing method for P-added high-strength steel | |
| JP2002030403A (en) | Hot dip galvannealed steel sheet and its production method | |
| JPH03111546A (en) | Production of highly corrosion resistant aluminized cr-containing steel sheet excellent in adhesive strength of plating | |
| JP2743228B2 (en) | Method for producing hot-dip aluminized Cr-containing steel sheet with excellent workability and plating adhesion | |
| JP2704819B2 (en) | Method for producing high-Si hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel sheet | |
| CN117960829B (en) | Method for producing hot stamping member and hot stamping member | |
| JP2001026852A (en) | Production of galvanized steel sheet and galvannealed steel sheet | |
| CN118256845A (en) | Continuous galvanizing process of thin galvanized substrate for color coating | |
| KR940000872B1 (en) | Method for making a hot-dipped zinc coating steel sheet with an excellent workability and plating properties | |
| JPH08100248A (en) | Method and equipment for producing galvannealed steel sheet | |
| CN115537652A (en) | Large-size television backboard hot galvanizing plate |