JPH03248703A - Work roll for hot rolling and its manufacture - Google Patents
Work roll for hot rolling and its manufactureInfo
- Publication number
- JPH03248703A JPH03248703A JP4245990A JP4245990A JPH03248703A JP H03248703 A JPH03248703 A JP H03248703A JP 4245990 A JP4245990 A JP 4245990A JP 4245990 A JP4245990 A JP 4245990A JP H03248703 A JPH03248703 A JP H03248703A
- Authority
- JP
- Japan
- Prior art keywords
- roll
- shaft material
- outer layer
- hot rolling
- work roll
- 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
- 238000005098 hot rolling Methods 0.000 title claims abstract description 18
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 239000000463 material Substances 0.000 claims abstract description 44
- 238000001816 cooling Methods 0.000 claims abstract description 12
- 238000000034 method Methods 0.000 claims abstract description 11
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 10
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 9
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 9
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 7
- 239000002184 metal Substances 0.000 claims abstract description 5
- 229910052751 metal Inorganic materials 0.000 claims abstract description 5
- 239000002893 slag Substances 0.000 claims abstract description 5
- 239000000126 substance Substances 0.000 claims abstract description 5
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 4
- 239000000956 alloy Substances 0.000 claims abstract description 4
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 4
- 229910052742 iron Inorganic materials 0.000 claims abstract 2
- 229910000831 Steel Inorganic materials 0.000 claims description 10
- 239000010959 steel Substances 0.000 claims description 10
- 229910001208 Crucible steel Inorganic materials 0.000 claims description 5
- 238000005096 rolling process Methods 0.000 abstract description 28
- 229910052799 carbon Inorganic materials 0.000 abstract description 7
- 238000005496 tempering Methods 0.000 abstract description 6
- 229910052748 manganese Inorganic materials 0.000 abstract description 5
- 239000000203 mixture Substances 0.000 abstract description 4
- 238000010791 quenching Methods 0.000 abstract description 3
- 230000000171 quenching effect Effects 0.000 abstract description 3
- 238000010438 heat treatment Methods 0.000 abstract description 2
- 238000005304 joining Methods 0.000 abstract description 2
- 230000008018 melting Effects 0.000 abstract description 2
- 238000002844 melting Methods 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 22
- 150000001247 metal acetylides Chemical class 0.000 description 21
- 230000000694 effects Effects 0.000 description 12
- 229910000997 High-speed steel Inorganic materials 0.000 description 10
- 239000002131 composite material Substances 0.000 description 7
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- 238000009750 centrifugal casting Methods 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 230000003746 surface roughness Effects 0.000 description 4
- 229910001018 Cast iron Inorganic materials 0.000 description 3
- 238000005299 abrasion Methods 0.000 description 3
- 238000002425 crystallisation Methods 0.000 description 3
- 230000008025 crystallization Effects 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 230000005496 eutectics Effects 0.000 description 3
- 238000005242 forging Methods 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910001566 austenite Inorganic materials 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000717 retained effect Effects 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 238000003462 Bender reaction Methods 0.000 description 1
- 206010013786 Dry skin Diseases 0.000 description 1
- 229910001141 Ductile iron Inorganic materials 0.000 description 1
- 229910001060 Gray iron Inorganic materials 0.000 description 1
- 230000005856 abnormality Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000007788 roughening Methods 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Reduction Rolling/Reduction Stand/Operation Of Reduction Machine (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は耐摩耗性、耐肌荒性に優れた胴表層部と、高負
荷に耐え得る十分な靭性をもつ軸部を兼ね備えた熱間圧
延用作業ロールに関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a hot-rolling motor that has a shell surface layer with excellent wear resistance and roughness resistance, and a shaft portion with sufficient toughness to withstand high loads. This invention relates to rolling work rolls.
従来の熱間圧延用作業ロールは、外層に耐摩耗性の大き
い炭化物を多く晶出させた合金鋳鉄系材料を用い、軸材
に靭性のあるねずみ鋳鉄、もしくは、ダクタイル鋳鉄を
用い、遠心鋳造法により製造した鋳鉄系の複合ロールが
主流であった。Conventional work rolls for hot rolling use an alloy cast iron material with a large amount of highly wear-resistant carbide crystallized in the outer layer, tough gray cast iron or ductile cast iron for the shaft material, and a centrifugal casting method. The mainstream was cast iron composite rolls manufactured by.
近年の熱間圧延の分野では、省エネルギ、生産性向上、
鋼材品質向上の立場から低温高圧下圧延が指向されてい
る。その結果、作業ロールにかかる負担は従来ロールと
比較して非常に大きくなり、そのため高負荷に堪え、し
かも、耐摩耗性、耐肌荒性に優れた作業ロールが要求さ
れている。In recent years, in the field of hot rolling, energy saving, productivity improvement,
From the standpoint of improving the quality of steel materials, low-temperature, high-reduction rolling is becoming more popular. As a result, the load placed on the work roll is much greater than that of conventional rolls, and there is therefore a need for a work roll that can withstand high loads and has excellent abrasion resistance and roughness resistance.
ところで、ロールの耐摩耗性を向上させるためには、炭
化物量の増加が有効であることが知られている。一方、
ロールの肌荒れは、ロール表面が熱延板と繰返し接触し
て、熱疲労と塑性疲労を受けるために微細な亀裂を生じ
ることに起因するものと考えられている。この疲労亀裂
は粗大な晶出炭化物に生じ、この炭化物に沿って進行す
る。従って、炭化物の増量は耐摩耗性の向上には有効で
あるが、反面肌荒性の劣化を招くという相反性がある。Incidentally, it is known that increasing the amount of carbide is effective in improving the wear resistance of the roll. on the other hand,
It is believed that the rough surface of the roll is caused by the roll surface repeatedly coming into contact with the hot-rolled sheet and undergoing thermal fatigue and plastic fatigue, resulting in the formation of fine cracks. These fatigue cracks occur in coarse crystallized carbides and propagate along these carbides. Therefore, although increasing the amount of carbide is effective in improving wear resistance, there is a trade-off in that it leads to deterioration in surface roughness.
従って、粗大な炭化物の網目状晶出を抑えることができ
れば耐肌荒性の向上が可能となる。Therefore, if the mesh crystallization of coarse carbides can be suppressed, the roughness resistance can be improved.
このような背景の下に添加炭素量を粗大な網目状炭化物
が晶出しない範囲、すなわち、大略１．８％以下に抑え
て設計されているアダマイトロールが開発されている。Against this background, Adamite rolls have been developed which are designed to suppress the amount of added carbon to a range in which coarse network carbides do not crystallize, that is, approximately 1.8% or less.
しかし、マダマイトロールでは添加炭素量が抑制される
ため、炭化物量の増加による耐摩耗性の向上には限界が
ある。このため、例えば、特公昭６２−１８２４１号公
報に記載のようにＴｉまたはＺｒ添加により粗大炭化物
の網目状晶出を防止し、添加Ｃ，Ｃｒ、Ｍｏ量を現状よ
り増加させ耐摩耗性向上と耐肌荒性向上を両立させるこ
とが可能な熱延用ロール材が提案されている。However, since the amount of added carbon is suppressed in madamite rolls, there is a limit to the improvement in wear resistance by increasing the amount of carbide. For this reason, for example, as described in Japanese Patent Publication No. 62-18241, it is possible to prevent mesh crystallization of coarse carbides by adding Ti or Zr, and increase the amount of added C, Cr, and Mo from the current level to improve wear resistance. A roll material for hot rolling has been proposed that can simultaneously improve surface roughness resistance.
しかし、ロールの肌荒れに関しては疲労亀裂の進展によ
るもののほか、晶出炭化物の圧延中の欠は落ちという要
因が考えられる。すなわち、圧延中にロール表面の晶出
炭化物が欠は落ちるとミクロキャビティ状の欠陥となり
、その欠陥を起点としてミクロ的な剥離や亀裂が発生す
るため肌荒れを促進する可能性が大きい。これに対して
は炭化物量の増加は、その炭化物が網目状に晶出してい
れば勿論のこと、均一に分散されて晶出している場合に
も逆効果であり、炭化物量の増加は耐肌荒性に対しては
問題である。However, the rough surface of the roll is thought to be caused not only by the growth of fatigue cracks but also by the cracking of crystallized carbides during rolling. That is, when the crystallized carbide on the roll surface falls off during rolling, it becomes a microcavity-like defect, and microscopic peeling or cracking occurs from the defect, which is highly likely to promote rough skin. On the other hand, an increase in the amount of carbides has the opposite effect not only if the carbides are crystallized in a network shape, but also if they are uniformly dispersed, and an increase in the amount of carbides has the opposite effect. There is a problem with roughness.
一方、最近の需要家の板製品への品質向上要求は増々厳
しくなっており、省エネルギ、及び、生産性向上という
製造側の指向と相まって、高圧下圧延や高形状制御圧延
等の圧延方法に対する施策も強力に推進されている。On the other hand, in recent years, demand from customers for improving the quality of plate products has become more and more severe.Coupled with manufacturers' orientation towards energy saving and productivity improvement, rolling methods such as high reduction rolling and high shape control rolling are becoming more and more demanding. Measures are also being strongly promoted.
これらの圧延に使用される圧延機は、従来の二段または
四段圧延機に替り、人殺圧延機あるいは異径ロール圧延
機が開発され普及しつつある。例えば、実開昭６２−１
３１７０５号公報記載の圧延機を用いる圧延のように、
これら新しい圧延機の普及により、作業ロールは径小化
及び大きな曲げが付与される等使用条件が過酷になって
きている。そのため、作業ロールとしては従来ロールよ
りも優れた耐摩耗性や耐肌荒性を要求されると同時に、
胴内部、及び、ネック部における強靭性が要求される。As rolling mills used for these rolling operations, instead of the conventional two-high or four-high rolling mills, artificial rolling mills or different diameter roll mills have been developed and are becoming popular. For example, Utsukai Showa 62-1
Like rolling using a rolling mill described in 31705,
With the spread of these new rolling mills, the operating conditions of work rolls have become more severe, such as reduction in diameter and large bending. Therefore, work rolls are required to have better abrasion resistance and roughness resistance than conventional rolls, and at the same time,
Toughness is required inside the body and in the neck.
これらの要求に対しては、前述の公報に記載のロール材
についても、一体型では靭性が劣るため満足できず、遠
心鋳造法により製造した複合ロールにおいても、外層材
質と軸材材質の組合せに制限があることより軸材の靭性
の点で問題があり、高耐摩耗性、高耐肌荒性と強靭性を
同時に満足させるのは困難であった。These requirements cannot be met even with the roll material described in the above-mentioned publication because of its inferior toughness, and even in composite rolls manufactured by centrifugal casting, the combination of outer layer material and shaft material Due to the limitations, there was a problem with the toughness of the shaft material, and it was difficult to simultaneously satisfy high wear resistance, high roughness resistance, and toughness.
本発明は上記従来技術の問題点を解決し、耐摩耗性、耐
肌荒性に優れ、しかも軸材が強靭で高負荷圧延に十分耐
用可能な熱間圧延用作業ロールを提供することを目的に
なされたものである。The object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a work roll for hot rolling that has excellent wear resistance and surface roughness resistance, has a strong shaft material, and can sufficiently withstand high-load rolling. This is what was done.
一般に耐摩耗性の向上には炭化物量の増加のほかに、高
硬度化が有効である。そして硬度を増加させるのに有効
な手段がＣｒ、Ｍｏ等の添加量を増やすことである。し
かし、これらの元素はいずれも粗大な共晶炭化物が現れ
るＣ量を下げる。従って、硬度の増加を目的としたＣｒ
、Ｍｏ等の元素の増量も耐肌荒性の面から限界がある。In addition to increasing the amount of carbide, increasing hardness is generally effective for improving wear resistance. An effective means for increasing hardness is to increase the amount of Cr, Mo, etc. added. However, all of these elements lower the amount of C at which coarse eutectic carbides appear. Therefore, Cr for the purpose of increasing hardness
There is also a limit to increasing the amount of elements such as , Mo, etc. from the viewpoint of roughening resistance.
また、ＶやＷ等は硬質の炭化物を生成するため、これら
の元素の増量により硬度を増加させることは粗大共晶炭
化物を防止しつつ高硬度化が可能であり、疲労亀裂によ
る肌荒れ防止に有効な手段と考えられるが、このような
炭化物を増加させることは炭化物の欠は落ちによる肌荒
れに対しては好ましいものではない。In addition, V, W, etc. generate hard carbides, so increasing the hardness by increasing the amount of these elements makes it possible to increase hardness while preventing coarse eutectic carbides, which is effective in preventing rough skin due to fatigue cracks. However, increasing the amount of carbides in this way is not preferable to prevent rough skin due to lack of carbides.
そこで、炭化物の増加による高硬度化をある程度に抑え
、基地の強化（高硬度化）により硬度を増加させて耐摩
耗性と耐肌荒性の向上を図ることが、この相反性の性能
向上を両立させる手法として考えられる。Therefore, it is possible to improve the performance of this reciprocity by suppressing the increase in hardness due to an increase in carbides and increasing the hardness by strengthening the base (increasing hardness) to improve wear resistance and roughness resistance. This can be considered as a method to achieve both.
鉄鋼切削用に開発された高速度鋼は、耐摩耗性には極め
て優れたものがあり、炭素添加量を抑えることにより共
晶炭化物の晶出を防止できると同時に、基地を高硬度化
して耐摩耗性の向上を図るには最適な材料である。ただ
し、靭性には劣るため高負荷圧延には一体型のロールで
は使用に耐えず、複合化が必要である。High-speed steels developed for steel cutting have extremely excellent wear resistance, and by reducing the amount of carbon added, it is possible to prevent the crystallization of eutectic carbides, and at the same time, by increasing the hardness of the base, it is possible to improve wear resistance. It is the best material for improving wear resistance. However, due to its inferior toughness, an integrated roll cannot withstand high-load rolling, and a composite roll is required.
しかし、軸材に強靭性を得るため銅系材料を適用した場
合、遠心鋳造法では外層材より軸材の方が高融点である
ため軸材を鋳込んだ時に外層が溶けて混合状態となった
境界部が最終凝固位置となり、境界部に鋳造欠陥が発生
し易いという欠点があり、製造不可能である。However, when a copper-based material is applied to the shaft material in order to obtain toughness, the outer layer melts and becomes mixed when the shaft material is cast because the shaft material has a higher melting point than the outer layer material in the centrifugal casting method. The final solidification position is at the boundary, and there is a drawback that casting defects are likely to occur at the boundary, making it impossible to manufacture.
そこで、本発明はあらかじめ形成した銅系軸材の周囲に
高速度鋼の溶湯を連続的に凝固、溶着させ複合ロールを
製造する方法に着目した。Therefore, the present invention focused on a method of manufacturing a composite roll by continuously solidifying and welding molten high-speed steel around a copper-based shaft material formed in advance.
本発明は上記の着目点から、上記目的を達成するため実
験追求を行って以下の知見を得た。In view of the above-mentioned points of interest, the present invention conducted experiments to achieve the above-mentioned objects, and obtained the following knowledge.
基本的には熱間圧延用作業ロールにおいて、硬さがＨＳ
８０以上で、化学成分が重量比でＣ：０．５−１．５％
、Ｓ ｉ ： ２．０％以下、Ｍｎ：１．５％以下、０
ｒ＝２〜６％、Ｍｏ：１５％以下、Ｗ：２０％以下、Ｖ
：０．５〜５％、Ｃｏ：５〜１３％、残部実質的にＦｅ
からなる高速度鋼の外層を軸材に接合した熱間圧延用作
業ロールである。ここにおいて、外層は耐摩耗性と耐肌
荒性を確保するため、高速度鋼とするとともに、熱処理
を施しＨＳ８０以上の硬さとする必要がある。Basically, the hardness of work rolls for hot rolling is HS.
80 or higher, the chemical component is C: 0.5-1.5% by weight
, S i: 2.0% or less, Mn: 1.5% or less, 0
r=2 to 6%, Mo: 15% or less, W: 20% or less, V
: 0.5-5%, Co: 5-13%, remainder substantially Fe
This is a work roll for hot rolling, in which an outer layer of high-speed steel is bonded to the shaft material. Here, in order to ensure wear resistance and roughness resistance, the outer layer must be made of high speed steel and must be heat treated to have a hardness of HS80 or higher.
尚、外層高速度鋼の化学成分の特定は次の理由による。The chemical composition of the outer layer high-speed steel is specified for the following reasons.
特に、Ｃ：０．８〜１．３％、Ｓ ｉ ： ０．３〜１
．０％、Ｍｎ ： ０．２〜０．８％、Ｃｒ：２〜６％
、Ｍｏは８〜１２％、 Ｗ： ０．５−３％、ＶＯ，８
〜２．５％、ｃｏ＝６〜１０％を含むものが好ましい。In particular, C: 0.8-1.3%, Si: 0.3-1
．． 0%, Mn: 0.2-0.8%, Cr: 2-6%
, Mo: 8-12%, W: 0.5-3%, VO, 8
~2.5%, preferably containing co=6 to 10%.
Ｃは耐摩耗性の向上のための炭化物の形状及び基地硬さ
の確保が必要である。その量が０．５％未満の場合、炭
化物量が少なく、耐摩耗性の点で十分でない。また、１
．５％ を超えると、網目状炭化物の晶出量が増加し、
耐肌荒性の点で劣ってしまう。０．８〜１．３％が好ま
しい。For C, it is necessary to ensure the shape of the carbide and the base hardness in order to improve wear resistance. When the amount is less than 0.5%, the amount of carbide is small and the wear resistance is not sufficient. Also, 1
．． When it exceeds 5%, the amount of crystallized network carbide increases,
It is inferior in roughness resistance. 0.8-1.3% is preferred.
Ｓｉは脱酸剤として必要な元素であり、また、焼戻し抵
抗性を高める。しかし、その量が２．０％を超えると脆
化が生じ易くなる。０．３〜１．０％が好ましい。Si is a necessary element as a deoxidizing agent and also improves tempering resistance. However, if the amount exceeds 2.0%, embrittlement tends to occur. 0.3 to 1.0% is preferred.
Ｍｎは脱酸作用とともに不純物であるＳをＭｎＳとして
固定する作用があるが、その量が１．５％を超えると残
留オーステナイト量が増え、安定して十分な硬さの維持
が困難となり、また、靭性も低下する。０．２〜０．８
％が好ましい。Mn has a deoxidizing effect and also has the effect of fixing impurity S as MnS, but if its amount exceeds 1.5%, the amount of retained austenite increases, making it difficult to maintain stable and sufficient hardness. , toughness also decreases. 0.2-0.8
% is preferred.
Ｃｒは２％未満では焼入性に劣り、６％を超えるとＣｒ
系炭化物が過多となり不都合である。If Cr is less than 2%, hardenability is poor, and if it exceeds 6%, Cr
This is inconvenient because the amount of carbides becomes excessive.
ＭＯ及びＷはそれぞれＭ ２Ｃ或いはＭＢＣ系炭化炭化
物成させ、且つ、基地中にも固溶して基地を強化し耐摩
耗性や焼戻し抵抗性を高める。しかし過剰になるとＭ
ｅ Ｃ系炭化物が増加し靭性及び耐肌荒性が低下する。MO and W form M2C or MBC-based carbides, respectively, and are also dissolved in the base to strengthen the base and improve wear resistance and tempering resistance. However, if it becomes excessive, M
e C-based carbide increases and toughness and roughness resistance decrease.
Ｍｏ及びＷの上限はそれぞれ１０％及び２０％であり、
２Ｍｏ＋Ｗが２０％以下であることが望ましい、Ｍｏは
８〜１２％、Ｗ二０．５〜３％が好ましい。The upper limits of Mo and W are 10% and 20%, respectively,
It is desirable that 2Mo+W is 20% or less, Mo is preferably 8 to 12%, and W is preferably 0.5 to 3%.
■はＭＣ系炭化物を形成し、耐摩耗性向上に寄与するが
、１％未満では十分な効果がなく、５％を超えると研削
性を著しく阻害する。０．８ 〜２．５％ が好ましい
。(2) forms MC-based carbides and contributes to improving wear resistance, but if it is less than 1%, it does not have a sufficient effect, and if it exceeds 5%, it significantly impairs grindability. 0.8 to 2.5% is preferable.
ＣＯは基地に固溶し焼戻し軟化抵抗を高めると共に、二
次硬化により高温焼戻しで高硬度を得るのに有効な元素
であるが、５％未満で・はその効果が小さく、１３％を
超えると靭性が低下する。６〜１０％が好ましい。CO is an effective element for increasing temper softening resistance by solid solution in the matrix and obtaining high hardness through high temperature tempering through secondary hardening, but the effect is small when it is less than 5%, and when it exceeds 13%. Toughness decreases. 6 to 10% is preferred.
尚、本発明の外層に用いる高速度鋼は上記元素のほかに
Ｎ１を含有することができる。Ｎｉは焼入性を向上する
作用をもつため、５％以下の量を添加することができる
。それを超えると残留オーステナイトの増加を招き、硬
度の低下や耐肌荒性の低下をきたす。Note that the high-speed steel used for the outer layer of the present invention may contain N1 in addition to the above-mentioned elements. Since Ni has the effect of improving hardenability, it can be added in an amount of 5% or less. Exceeding this will lead to an increase in retained austenite, resulting in a decrease in hardness and roughness resistance.
これらの元素以外は不純物を除いて実質的にＦｅから成
る。不純物として主なものはＰ及びＳであり、脆化防止
のためＰ及びＳともに０．１ ％以下であることが望ま
しい。Elements other than these are substantially composed of Fe, excluding impurities. The main impurities are P and S, and it is desirable that both P and S be 0.1% or less to prevent embrittlement.
次に、本発明では鋳鋼、または、鍛鋼から成る軸材を用
い、ネック部の表面硬さをＨＳ３５以上とすることを要
旨とする。すなわち、本発明のロールに公称応力として
１０ｋｇ／ｗＩ２のネック応力が加えられた場合、寸法
効果係数０．８９表面効果係数０．９．切欠き係数２．
０として、必要な疲れ限度は３６ｋｇ／ｎｕ２となり、
それを得るためには硬さとしてＨＳ３５以上が必要とな
る。Next, the present invention uses a shaft material made of cast steel or forged steel, and the surface hardness of the neck portion is set to HS35 or higher. That is, when a neck stress of 10 kg/wI2 is applied as a nominal stress to the roll of the present invention, the dimensional effect coefficient is 0.89 and the surface effect coefficient is 0.9. Notch factor 2.
0, the required fatigue limit is 36 kg/nu2,
In order to achieve this, a hardness of HS35 or higher is required.
次に本発明における外層と外層とを接合させる方法とし
ては前述の通り遠心鋳造法では健全に接合させることは
不可能であるため、回転付与エレクトロスラグ再溶解に
よる連続肉盛（複合）方法を適用し、本発明ロールを製
造することを要旨とする。すなわち、軸材と聞忘的に配
置されたモールドとの間に形成される空隙に高速度鋼か
ら成る消耗電極を挿入し、軸材及び冷却モールドを円周
方向に同期的に回転させながらスラグ浴の下でエレクト
ロスラブ再溶解法により消耗電極を溶解させるとともに
、溶湯を冷却モールドに接触させ凝固させることにより
形成した外層を軸材に溶着させる方法である。Next, as a method for joining the outer layers in the present invention, since it is impossible to join the outer layers soundly with the centrifugal casting method as described above, a continuous overlay (composite) method using electroslag remelting by applying rotation is applied. The gist is to manufacture the roll of the present invention. In other words, a consumable electrode made of high-speed steel is inserted into the gap formed between the shaft material and a mold arranged in a memoristic manner, and the shaft material and the cooling mold are rotated synchronously in the circumferential direction while the slag In this method, the consumable electrode is melted by electroslab remelting method under a bath, and the outer layer formed by bringing the molten metal into contact with a cooling mold and solidifying it is welded to the shaft material.
第１図は、本発明ロールの製造に使用可能な装置の一例
を示したものである。本装置は内部を水冷される冷却モ
ールド１とそれに聞忘的に配置された軸材２、及び、点
火板３と軸材２をのせる回転定盤４から成る。冷却モー
ルド１と軸材２との間に形成される空隙に高速度鋼から
成る消耗電極５を挿入し、回転定盤４と消耗電極５の間
にカーボンブラシ６を通して電流を流し、冷却モールド
１、軸材２９点点火板及び回転定盤４を同期的に円周方
向に回転させながら、溶融スラグ７の抵抗熱により消耗
電極５を溶解する。溶湯は冷却モールド１に接触凝固し
、外層８を形成する。このようにして得られた作業ロー
ルは、更に焼入れ焼戻し等の熱処理を施すことによりＨ
Ｓ８０以上の硬さを得る。FIG. 1 shows an example of an apparatus that can be used to manufacture the roll of the present invention. This device consists of a cooling mold 1 whose interior is water-cooled, a shaft member 2 disposed intermittently therein, and a rotating surface plate 4 on which an ignition plate 3 and the shaft member 2 are placed. A consumable electrode 5 made of high-speed steel is inserted into the gap formed between the cooling mold 1 and the shaft material 2, and a current is passed through the carbon brush 6 between the rotating surface plate 4 and the consumable electrode 5, and the cooling mold 1 The consumable electrode 5 is melted by the resistance heat of the molten slag 7 while rotating the shaft member 29, the ignition plate, and the rotating surface plate 4 in the circumferential direction synchronously. The molten metal contacts the cooling mold 1 and solidifies to form an outer layer 8. The work roll obtained in this way is further heat treated such as quenching and tempering to achieve H
Obtain hardness of S80 or higher.
軸材には、引張強さ５５ ｋｇ ／ ａｎ２以上、衝撃
値２ ｋｇ −ｍ ／ ｃｉ以上の鍛鋼又は鋳鋼が好ま
しい。特に、Ｃ：０．２〜１．５％、Ｓｉ：３％以下、
Ｍｎ：２％以下、Ｃｒ５％以下を含むものが好ましい。The shaft material is preferably forged steel or cast steel with a tensile strength of 55 kg/an2 or more and an impact value of 2 kg-m/ci or more. In particular, C: 0.2 to 1.5%, Si: 3% or less,
Preferably, it contains Mn: 2% or less and Cr 5% or less.
他、Ｎｉ ： ０．５％以下、Ｍｏ：１％以下を含むこ
とができる。特に、Ｃ： ０．４〜１．０％、Ｓｉ二０
．１〜１％、Ｍｎ ： ０．２〜１％、Ｃｒ：１〜３．
５％、Ｍｏ ： ０．１〜０．５％、残Ｆｅからなる鍛
鋼が好ましい。Ｃｒは１．５％以上がより好ましい。In addition, Ni: 0.5% or less and Mo: 1% or less may be included. In particular, C: 0.4-1.0%, Si20
．． 1-1%, Mn: 0.2-1%, Cr: 1-3.
5%, Mo: 0.1 to 0.5%, and the balance Fe is preferably forged steel. Cr is more preferably 1.5% or more.
上記の構成による熱間圧延用作業ロールは、基地を高硬
度化された高速度鋼を外層に用いているため、耐摩耗性
の向上と耐肌荒性の向上が同時に可能となる。また、複
合ロールとして軸材に強靭な鋳鋼、または、鍛鋼を用い
ているため、高負荷圧延や大きな曲げが加わる圧延に使
用されても十分耐用できるものとなる。特に、エレクト
ロスラグ再溶解により外層を軸材に溶着させたロールで
あるため、溶湯から晶出する炭化物は偏析をおこさず外
層中に微細、かつ、均等に分散したものとなり、耐摩耗
性、耐肌荒性が向上すると同時に、圧延材の表面性状の
品質が向上する。Since the hot rolling work roll having the above structure uses high-speed steel with a high hardness base for the outer layer, it is possible to improve wear resistance and roughness resistance at the same time. Furthermore, since the composite roll uses strong cast steel or forged steel for its shaft material, it can withstand sufficient durability even when used for high-load rolling or rolling that involves large bending. In particular, since the outer layer is welded to the shaft material by electroslag remelting, the carbides crystallized from the molten metal do not segregate and are finely and evenly dispersed in the outer layer, resulting in improved wear resistance and resistance. At the same time, the surface roughness of the rolled material is improved and the surface quality of the rolled material is improved.
本発明のロールは溶着後に自由鍛造により熱間鍛造する
ことが好ましい。鍛造比は１．５〜３が好ましい。鍛造
を施すことにより約１．５倍耐クラツク性が向上する。The roll of the present invention is preferably hot forged by free forging after welding. The forging ratio is preferably 1.5 to 3. Forging improves crack resistance by about 1.5 times.
本発明の一実施例として、胴径６００ｎｎ、ＩＪＭ長１
７２０ｎａの熱間圧延用作業ロールを第１図に示す装置
により製造した。この時の外層材質の化学成分を第１表
に示す。このロールは肉盛したままのものに更に１１０
０〜１２００℃からの焼入れ、及び、５００〜５５０℃
での焼戻しの熱処理を施した。得られたロールの外層表
面硬さ（ＨＳ）を第１表に併せ示す。As an embodiment of the present invention, a body diameter of 600 nn and an IJM length of 1
A 720 na hot rolling work roll was manufactured using the apparatus shown in FIG. The chemical composition of the outer layer material at this time is shown in Table 1. This roll is 110 yen more than the one with the filling.
Quenching from 0 to 1200℃ and 500 to 550℃
Heat treatment for tempering was performed. Table 1 also shows the outer layer surface hardness (HS) of the obtained roll.
第 １ 表
尚、本実施例ロールの軸材にはＣ： ０．９１％、Ｓｉ
：０．５８％、Ｍｎ：０．７０％、Ｃｒ：３．０１％、
Ｍｏ：Ｑ、１８％、残Ｆｅよりなる３％Ｃｒ鍛鋼を用い
、そのネック部の硬さはＨＳ４０であった。また、ロー
ル胴端余長部で調査した外層と軸材の接合部には異常は
認められず健全であることを確認した。ロールとしてス
トレートなものとクラウンを有するものを製造した。Table 1 Note that the shaft material of the roll of this example contains C: 0.91%, Si
: 0.58%, Mn: 0.70%, Cr: 3.01%,
A 3% Cr forged steel consisting of Mo:Q, 18%, and residual Fe was used, and the hardness of the neck portion thereof was HS40. In addition, no abnormality was observed in the joint between the outer layer and the shaft material, which was examined at the excess length of the roll body end, and it was confirmed that the joint was sound. A straight roll and a crowned roll were manufactured.
第２図に示すように肉盛外層９は胴部に設け、軸部１０
は軸材によって構成した。As shown in FIG.
is composed of shaft members.
本実施例ロールを用い、垂直ベンダを有するものとそれ
が無いものの圧延機によって普通鋼の熱間圧延を行った
。比較のため高合金鋳鉄材を外層とした従来タイプのロ
ールも圧延に供した。この圧延によって得られた摩耗デ
ータを第３図に示す。Using the rolls of this example, common steel was hot rolled using rolling mills with and without vertical benders. For comparison, a conventional roll with a high-alloy cast iron outer layer was also used for rolling. The wear data obtained by this rolling is shown in FIG.
耐摩耗性については、第３図から明らかなように、従来
ロールの四倍以上の性能の向上が可能であることが確認
された。耐肌荒性については第４図より大きな炭化物の
欠は落ち、或いは、亀裂発生は見られず、外観観察でも
、圧延後にも、ロール表面は極めて滑らかな肌であり、
本発明の目的である晶出炭化物を抑制し基地硬度を増加
させることによる耐肌荒性の向上が十分効果があること
が確認された。以上の結果より本発明ロールは耐摩耗性
、耐肌荒性の向上に関し、十分要求を満足するものであ
った。As for the wear resistance, as is clear from FIG. 3, it was confirmed that the performance could be improved by more than four times that of the conventional roll. As for roughness resistance, as shown in Figure 4, no large carbide chips were removed or cracks were observed, and the roll surface was extremely smooth both in appearance and after rolling.
It was confirmed that the objective of the present invention, which is to suppress crystallized carbides and increase base hardness, to improve skin roughness resistance is sufficiently effective. From the above results, the roll of the present invention fully satisfies the requirements regarding improvement in abrasion resistance and roughness resistance.
更に、本発明ロールは折損及び剥離等の事故の発生がな
く順澗に使用され、高負荷圧延に十分耐用可能であった
。Further, the roll of the present invention was used successfully without any accidents such as breakage or peeling, and was sufficiently durable for high-load rolling.
第４図及び第５図は本実施例の複合ロールをワークロー
ル１１として用いた熱間圧延機のロール構成を示すもの
である。１２は被圧延材、１３はバックアップロール、
１４は中間ロールである。4 and 5 show the roll configuration of a hot rolling mill using the composite roll of this example as the work roll 11. FIG. 12 is a material to be rolled, 13 is a backup roll,
14 is an intermediate roll.
←はロールの水平移動を示す矢印である。← is an arrow indicating horizontal movement of the roll.
本発明は、以上説明したように構成されているので以下
に記載されるような効果を奏する。Since the present invention is configured as described above, it produces the effects described below.
外層材に本発明特定の高速度鋼を用いることにより、従
来に比べて非常に優れた耐摩耗性と耐肌荒性を熱間圧延
用作業ロールに付与できる。また強靭性の鋳鋼又は鍛鋼
の軸材を用い、ネック部の表面硬さをＨＳ３５以上にす
ることにより、高負荷圧延にも十分使用可能な熱間圧延
用作業ロールを製造することができる。By using the high speed steel specified by the present invention for the outer layer material, it is possible to impart extremely superior wear resistance and roughness resistance to the hot rolling work roll compared to conventional ones. Further, by using a strong cast steel or forged steel shaft material and making the surface hardness of the neck portion HS35 or higher, it is possible to manufacture a work roll for hot rolling that can be sufficiently used for high-load rolling.
第１図は本発明の一実施例の連続肉盛装置の説明図、第
２図は本発明の実施例ロールの断面図、第３図は本発明
の実施例ロールと従来ロールの圧延後の摩耗データーを
示す説明図、第４図及び第５図は本発明の実施例ロール
を用いた圧延機のロール説明図である。
１・・・冷却モールド、２・・・軸材、３・・・点火板
、４・・回転定盤、５・・・消耗電極、６・・・カーボ
ンブラシ、７・・・溶融スラグ、８・・・外層、９・・
・肉盛層、１０・・・軸材、１１・・・ワークロール、
１２・・・被圧延材、第
囚
第２図
第
３
因
００
１θθＯ
圧延トン数 （ｔａｎ）
第
図
第
図Fig. 1 is an explanatory diagram of a continuous overlay device according to an embodiment of the present invention, Fig. 2 is a cross-sectional view of an embodiment roll of the present invention, and Fig. 3 is an illustration of an embodiment roll of the present invention and a conventional roll after rolling. FIGS. 4 and 5 are explanatory diagrams showing wear data of a rolling mill using an example roll of the present invention. DESCRIPTION OF SYMBOLS 1... Cooling mold, 2... Shaft material, 3... Ignition plate, 4... Rotating surface plate, 5... Consumable electrode, 6... Carbon brush, 7... Molten slag, 8 ...Outer layer, 9...
・Build-up layer, 10... Shaft material, 11... Work roll,
12... Rolled material, Figure 2 Figure 3 Factor 00 1θθO Rolling tonnage (tan) Figure Figure
Claims (1)
比でＣ：０．５％〜１．５％、Ｓｉ：３．０％以下、Ｍ
ｎ：１．５％以下、Ｃｒ：２〜６％、Ｍｏ：１０％以下
、Ｗ：２０％以下、Ｖ：１〜５％、Ｃｏ：５〜１３％、
残部実質的にＦｅから成り、表面硬さがＨＳ８０以上の
外層を軸材に冶金的に接合したことを特徴とする熱間圧
延用作業ロール。 ２、請求項１において、鋳鋼または鍛鋼から成る軸材を
用い、ネック部の表面硬さがＨＳ３５以上である熱間圧
延用作業ロール。 ３、請求項１において、軸材と同芯的に配置されたモー
ルドとの間に形成される空隙に鉄基合金から成る消耗電
極を挿入し、軸材及び冷却モールドを円周方向に同期的
に回転させながらスラグ浴の下でエレクトロスラグ再溶
解法により消耗電極を溶解させ、溶湯を冷却モールドに
接触させて、凝固させることにより形成した外層を軸材
に溶着させる熱間圧延用作業ロールの製造方法。[Claims] 1. In a work roll for hot rolling, the chemical components are C: 0.5% to 1.5%, Si: 3.0% or less, M
n: 1.5% or less, Cr: 2-6%, Mo: 10% or less, W: 20% or less, V: 1-5%, Co: 5-13%,
A work roll for hot rolling, characterized in that an outer layer, the remainder of which is substantially made of Fe and has a surface hardness of HS80 or higher, is metallurgically bonded to a shaft member. 2. The work roll for hot rolling according to claim 1, wherein the shaft material is made of cast steel or forged steel, and the surface hardness of the neck portion is HS35 or higher. 3. In claim 1, a consumable electrode made of an iron-based alloy is inserted into the gap formed between the shaft material and the mold arranged concentrically, and the shaft material and the cooling mold are synchronously moved in the circumferential direction. The consumable electrode is melted by the electroslag remelting method under a slag bath while rotating, and the molten metal is brought into contact with a cooling mold to solidify and weld the outer layer formed to the shaft material. Production method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4245990A JPH03248703A (en) | 1990-02-26 | 1990-02-26 | Work roll for hot rolling and its manufacture |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4245990A JPH03248703A (en) | 1990-02-26 | 1990-02-26 | Work roll for hot rolling and its manufacture |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03248703A true JPH03248703A (en) | 1991-11-06 |
Family
ID=12636658
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4245990A Pending JPH03248703A (en) | 1990-02-26 | 1990-02-26 | Work roll for hot rolling and its manufacture |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03248703A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000051756A1 (en) * | 1999-02-26 | 2000-09-08 | Kanto Special Steel Works, Ltd. | Roll for rolling |
-
1990
- 1990-02-26 JP JP4245990A patent/JPH03248703A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000051756A1 (en) * | 1999-02-26 | 2000-09-08 | Kanto Special Steel Works, Ltd. | Roll for rolling |
| GB2367075A (en) * | 1999-02-26 | 2002-03-27 | Kanto Special Steel Works Ltd | Roll for rolling |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0646052B1 (en) | Rolls for metal shaping | |
| EP0309587B1 (en) | Abrasion-resistant composite roll and process for its production | |
| JPS6247626B2 (en) | ||
| US5081760A (en) | Work roll for metal rolling | |
| WO1997048505A1 (en) | Hot rolling roll excellent in abrasion resistance and reduced in segregation of carbide | |
| JP2708611B2 (en) | Composite roll for cold rolling and production method thereof | |
| JP5726114B2 (en) | Recycling method of used roll composite rolls | |
| JP2687732B2 (en) | Composite roll for metal rolling, its manufacturing method and rolling mill | |
| JPH09209073A (en) | Composite sleeve for roll for rolling wide flange shape | |
| JP5268431B2 (en) | Recycling method of used roll composite rolls | |
| JP2012110968A5 (en) | ||
| JP5458654B2 (en) | Work roll for hot rolling mill and its manufacturing method | |
| JP2910434B2 (en) | Composite roll for hot rolling and its manufacturing method | |
| JP2006297427A (en) | Method for manufacturing forged sleeve roll for rolling wide flange shape | |
| JPH03248703A (en) | Work roll for hot rolling and its manufacture | |
| JPH0390270A (en) | Hot rolling work roll and rolling method | |
| JPS6332543B2 (en) | ||
| KR100245471B1 (en) | Complex roll and its manufacturing method for metal rolling | |
| JPH03126838A (en) | Composite roll | |
| JP3030077B2 (en) | Abrasion-resistant composite roll excellent in crack resistance and method for producing the same | |
| JP3047584B2 (en) | Work roll for cold rolling | |
| JPH0225205A (en) | Hot rolling use working roll and its rolling method | |
| JPS6358215B2 (en) | ||
| JP5760074B2 (en) | Recycled composite roll | |
| JP3116585B2 (en) | Manufacturing method of rolls for hot rolling |