JPH03219048A - Rolling roll made of forged steel excellent in wear resistance and thermal shock properties and its manufacture - Google Patents
Rolling roll made of forged steel excellent in wear resistance and thermal shock properties and its manufactureInfo
- Publication number
- JPH03219048A JPH03219048A JP22100190A JP22100190A JPH03219048A JP H03219048 A JPH03219048 A JP H03219048A JP 22100190 A JP22100190 A JP 22100190A JP 22100190 A JP22100190 A JP 22100190A JP H03219048 A JPH03219048 A JP H03219048A
- Authority
- JP
- Japan
- Prior art keywords
- less
- wear resistance
- thermal shock
- rolling roll
- steel
- 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 35
- 239000010959 steel Substances 0.000 title claims abstract description 35
- 230000035939 shock Effects 0.000 title claims abstract description 19
- 238000005096 rolling process Methods 0.000 title claims description 22
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 238000005496 tempering Methods 0.000 claims abstract description 29
- 229910001566 austenite Inorganic materials 0.000 claims abstract description 25
- 229910000734 martensite Inorganic materials 0.000 claims abstract description 19
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 10
- 230000000717 retained effect Effects 0.000 claims abstract description 10
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 9
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 8
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 6
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 6
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 6
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 5
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 5
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 5
- 238000000034 method Methods 0.000 claims description 11
- 238000001816 cooling Methods 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 7
- 230000008569 process Effects 0.000 claims description 7
- 229910001339 C alloy Inorganic materials 0.000 claims description 6
- 239000012535 impurity Substances 0.000 claims description 6
- 229910052742 iron Inorganic materials 0.000 claims description 5
- 150000001247 metal acetylides Chemical class 0.000 abstract description 13
- 238000005097 cold rolling Methods 0.000 abstract description 8
- 229910052799 carbon Inorganic materials 0.000 abstract description 6
- 239000011159 matrix material Substances 0.000 abstract description 5
- 238000005242 forging Methods 0.000 abstract description 3
- 229910052751 metal Inorganic materials 0.000 abstract description 3
- 239000002184 metal Substances 0.000 abstract description 3
- 230000009466 transformation Effects 0.000 abstract description 2
- 229910000851 Alloy steel Inorganic materials 0.000 abstract 1
- 150000002739 metals Chemical class 0.000 abstract 1
- 239000007787 solid Substances 0.000 abstract 1
- 238000010791 quenching Methods 0.000 description 16
- 230000000171 quenching effect Effects 0.000 description 14
- 238000010438 heat treatment Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- 230000007423 decrease Effects 0.000 description 5
- 238000001556 precipitation Methods 0.000 description 4
- 239000006104 solid solution Substances 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 238000005336 cracking Methods 0.000 description 3
- 150000004767 nitrides Chemical class 0.000 description 3
- 238000004901 spalling Methods 0.000 description 3
- 238000005299 abrasion Methods 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 230000005496 eutectics Effects 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 230000035882 stress Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- -1 C: 0.5-0.8 wt% Inorganic materials 0.000 description 1
- 206010057040 Temperature intolerance Diseases 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 239000000839 emulsion Substances 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000008543 heat sensitivity Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000005461 lubrication Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000010309 melting process Methods 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 235000010446 mineral oil Nutrition 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 230000001376 precipitating effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000008542 thermal sensitivity Effects 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- 230000001131 transforming effect Effects 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)
- Heat Treatment Of Articles (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は金属の冷間圧延用ロールにかかわり、耐摩耗性
が優れ、かつスリップ、絞り込み笠の圧延事故の被害の
小さい耐事故（熱衝撃）性に優れた鍛鋼製焼入れ焼戻し
圧延ロールおよびその製造法に関するものである。[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a roll for cold rolling of metal, which has excellent wear resistance and is accident resistant (thermal shock ) The present invention relates to a forged steel quenched and tempered rolling roll with excellent properties and a manufacturing method thereof.
〈従来の技術〉
従来鋼帯等の金属冷間圧延ロールとしては、車！ｉｉ比
でＣ： ０．７５〜０．９５％、Ｃ「：２〜５％、Ｍｏ
二０．１５〜０．５５％の成分を基本とし、Ｎｉ ：
１．０％以下、Ｖ：０，５％以下を適宜添加した鍛鋼製
焼入ロールが使用されてきた。しかしながら、最近の冷
間圧延１１〜ルにおいては、ロール原単位の向上、高圧
下圧延、スケジュールフリー圧延などの要求が進み、ロ
ールの使用条件は苛酷化の一途をたどっており、スリッ
プ、絞り込み等の圧延事故による熱衝撃の被害も大きく
なってきている。これらの圧延事故の際、熱衝撃により
ロールの表面に発生ずるクラックは、温度上昇に伴う熱
膨張が拘束されたために生した塑性ひずみが、冷却の際
に大きな引張応力に変換されたために発生すると考えら
れている。<Conventional technology> Conventional metal cold rolling rolls for steel strips, etc. have been used in cars! ii ratio: C: 0.75-0.95%, C: 2-5%, Mo
2.Basically contains 0.15 to 0.55% of Ni:
Forged steel quenching rolls to which 1.0% or less of V and 0.5% or less of V are appropriately added have been used. However, in recent cold rolling, the requirements for improved roll consumption, high reduction rolling, schedule-free rolling, etc. are increasing, and the conditions for using rolls are becoming more and more severe, such as slipping, squeezing, etc. The damage caused by thermal shock due to rolling accidents is also increasing. The cracks that occur on the surface of the rolls due to thermal shock during these rolling accidents are thought to occur because plastic strain caused by restraint of thermal expansion due to temperature rise is converted into large tensile stress during cooling. It is considered.
このクラックはロール原単位の低下をもたらすだけでは
なく スポーリングの起点となる。しかし、これらの圧
延事故を皆無にすることは困難であるが、熱衝撃による
クランクの発生しにくい、また発生したとしても小さく
てすむような耐事故性にイ３れたロールが要求されてい
る。また、スリップは摩耗により初期ネ■度が低下した
時に発生し易く、ロールの原単位の面からも耐摩耗性に
優れたロール材質が要求されている。These cracks not only reduce the roll consumption rate but also become the starting point for spalling. However, it is difficult to completely eliminate these rolling accidents, but there is a need for rolls that are highly resistant to accidents, so that cranks are less likely to occur due to thermal shock, and even if they do occur, they will be small. . In addition, slipping is likely to occur when the initial stiffness decreases due to wear, and roll materials with excellent wear resistance are required from the standpoint of roll unit consumption.
〈発明が解決しようとする課題〉
従来のロールは、組織的には低温焼戻しマルテンサイト
が主体であり、他に１０％以下の炭・窒化物と、１０％
以下の残留オーステナイトからなっている。従って耐摩
耗性は残留炭・窒化物量及びマｉ・りンクスの硬さに依
存し、１０％以下の炭・窒化物量では充分ではない。<Problem to be solved by the invention> The structure of conventional rolls is mainly composed of low-temperature tempered martensite, with 10% or less of carbon/nitride, and 10% of martensite.
It consists of the following retained austenite. Therefore, wear resistance depends on the amount of residual carbon/nitride and the hardness of the i-links, and a carbon/nitride amount of 10% or less is not sufficient.
また、焼入れ深度を大きくし、目標とする深さ位置まで
充分な焼入れ硬さを得ようとすれば、冷却速度の大きい
表面側は焼入れ後多くの残留オステナイトが存在し、充
分な焼入れ硬さを得ることができないため、焼入れ冷却
後一定時間内にサブゼロ処理（低温処ＩＩ）を行う必要
があった。In addition, if you increase the quenching depth and try to obtain sufficient quenching hardness to the target depth position, there will be a lot of residual austenite on the surface side where the cooling rate is high after quenching, making it difficult to obtain sufficient quenching hardness. Therefore, it was necessary to perform sub-zero treatment (low temperature treatment II) within a certain period of time after quenching and cooling.
また、サブゼロ処理の後更に硬さ調整等の目的で焼戻し
を行うが、その場合２００℃以下の低温焼戻しを行わな
ければ、焼戻しによる硬さ低下のため耐摩耗性が低下し
、また、低温焼戻しであるため熱感受性が大きく、圧延
事故の影響つまり耐事故（熱！ｉ窄）性の点でも問題が
あった。In addition, after the sub-zero treatment, tempering is further performed for the purpose of hardness adjustment, etc. In that case, if low temperature tempering is not performed at a temperature of 200°C or less, the wear resistance will decrease due to the decrease in hardness due to tempering. Therefore, it is highly sensitive to heat, and there are also problems in terms of resistance to rolling accidents, that is, accident resistance (heat shrinkage).
本発明の目的は、これらの問題を解決し、耐摩耗性、耐
事故性に優れた冷間圧延用ロールおよびその製造法を提
供するものである。An object of the present invention is to solve these problems and provide a cold rolling roll with excellent wear resistance and accident resistance, and a method for manufacturing the same.
〈課題を解決するための手段〉
すなわち、本発明は、高炭素合金鋼からなる鍛鋼製焼入
れ焼戻し圧延ｒ１〜ルの組織構成が、焼戻し時の冷却過
程でオーステナイトからマルテンサイトへ変態した相５
０〜８０％、焼戻しマルテンサイト相５０％以下、残部
が実質的に１５％以下の残留オーステナイト相からなる
ことを特徴とする耐摩耗性および熱ｆＪｉ〒性に優れた
鍛鋼製圧延ロールであり、望ましくは高炭素合金鋼が、
Ｃ：０．５〜０．８ ｗｔ％、Ｓｉ ： ０．５〜１
．５ ｗｔ％、Ｍｎ： ０．１〜１．０〜ｔ％、Ｎｉ
： ０．１〜１．０ｗｔ％、Ｃｒ ： ３．０〜
６．５ ｗｔ％、Ｍｏ ： ２．０〜５．０ｗｔ％、
Ｖ ： ２．１〜３．０ｗｔ％、Ｐ：０．０２０ｗｔ
％以下、Ｓ ： ０．０１０ｗｔ％以下を含有し、さら
に必要に応じてＷ、 ７．ｒ、 Ｔｉ、 Ｃｏ、Ｎｂの
１種または２種以上を合計で０．５〜３．０ｗｔ％含み
、残部がＦｅおよび不可避的不純物よりなる鋼である鍛
鋼製圧延ロールであり、またＣ：０．５〜０．８ ｗｔ
％、Ｓｉ ： ０．５〜１．５ ｗｔ％、Ｍｎ ：
０．１〜１．０ｗｔ％、Ｎｉ：０、Ｉ〜１．０ｗｔ％、
Ｃｒ ： ３．０〜６．５ ｗｔ％、Ｍｏ： ２．
０〜５．Ｑ ｗｔ％、Ｖ：２．１〜３．Ｑ ｗｔ％、Ｐ
： ０．０２０ｗｔ％以下、Ｓ ： ０．０１０ｗ
ｔ％以下を含み、さらに必要に応じてＷ、 Ｚｒ、 Ｔ
ｉ、 Ｃｏ、Ｎｂの１種または２種以上を合計で０．２
〜３．０４％含有し、残部がＦｅおよび不可避的不純物
よりなる素材を１０５０〜１２００℃の温度に加熱、強
制冷却を行い、残留オーステナイトが５０％以上となる
組織とした後、４００〜６００℃の温度で焼戻しを行う
ことを特徴とする耐摩耗性および熱ｄｉ！性に優れた鍛
鋼製圧延ロールの製造方法である。<Means for Solving the Problems> That is, the present invention provides a structure in which the structure of the quenched and tempered rolled forged steel R1 to R1 made of high carbon alloy steel is a phase 5 that is transformed from austenite to martensite during the cooling process during tempering.
0 to 80%, a tempered martensite phase of 50% or less, and the remainder substantially of 15% or less of a retained austenite phase. Preferably high carbon alloy steel,
C: 0.5-0.8 wt%, Si: 0.5-1
．． 5 wt%, Mn: 0.1-1.0-t%, Ni
: 0.1~1.0wt%, Cr: 3.0~
6.5 wt%, Mo: 2.0 to 5.0 wt%,
V: 2.1-3.0wt%, P: 0.020wt
% or less, S: contains 0.010 wt% or less, and further includes W as necessary.7. It is a forged steel rolling roll containing a total of 0.5 to 3.0 wt% of one or more of r, Ti, Co, and Nb, with the balance consisting of Fe and unavoidable impurities, and C:0 .5~0.8wt
%, Si: 0.5 to 1.5 wt%, Mn:
0.1 to 1.0 wt%, Ni: 0, I to 1.0 wt%,
Cr: 3.0-6.5 wt%, Mo: 2.
0-5. Q wt%, V: 2.1-3. Q wt%, P
: 0.020wt% or less, S: 0.010w
Contains t% or less, and further contains W, Zr, T as necessary
One or more of i, Co, and Nb in a total of 0.2
A material containing ~3.04% and the remainder consisting of Fe and unavoidable impurities is heated to a temperature of 1050 to 1200°C, forcedly cooled to create a structure with residual austenite of 50% or more, and then heated to 400 to 600°C. Wear resistance and heat di! characterized by tempering at a temperature of ! This is a method for manufacturing forged steel rolling rolls with excellent properties.
〈作 用〉
本発明は、組成と熱処理の組合せにより、熱感受性の低
い安定なＸ、１１織をｊｉ）、際立った耐事故性の向」
二をはかったものである。<Function> By combining the composition and heat treatment, the present invention creates a stable X, 11 weave with low heat sensitivity and outstanding accident resistance.
It is the sum of two.
即ち、Ｃ添加量を抑制し、造塊段階で晶出する巨大な共
晶状炭化物を極力少なくすることで靭性延性を冨ま−ｌ
、さらにＣｒ、 Ｍｏ、■を通り添加することにより微
細な複合炭化物の分散を可能にしたものである。In other words, by suppressing the amount of C added and minimizing the large eutectic carbides that crystallize during the agglomeration stage, toughness and ductility can be increased.
, and further added Cr, Mo, and ■ to enable the dispersion of fine composite carbides.
まず、本発明の相構成についてその限定理由を説明する
０本発明鋼は高炭素合金鋼を焼入れ焼戻ししたものであ
り、特に焼戻し処理による二次硬化を利用したものであ
る。First, the reasons for limiting the phase structure of the present invention will be explained. The steel of the present invention is made by quenching and tempering high carbon alloy steel, and particularly utilizes secondary hardening through tempering treatment.
本発明の望ましい焼戻し温度は４００〜６００℃である
が、４００〜６００℃の焼戻し保持過程では炭化物の析
出が生じるとともに残留オーステナイ１〜（ｒ＋＋）は
炭化物の析出によって合金濃度が低ドし不安定となる。The preferred tempering temperature of the present invention is 400 to 600°C, but carbide precipitation occurs during the tempering and holding process at 400 to 600°C, and the residual austenite 1 to (r++) becomes unstable because the alloy concentration decreases due to the carbide precipitation. becomes.
この状態から焼戻し後の冷却過程において残留オーステ
ナイト（γ□）がマルテンサイ！・（ＦＭ）へ変態する
。From this state, during the cooling process after tempering, residual austenite (γ□) changes to martensite!・Transforms into (FM).
また、焼入れ時に変態したマルテンサイトは、焼戻し保
持過程で炭化物の析出した焼戻しマルテンサイト（ＴＭ
）になる。In addition, martensite transformed during quenching is tempered martensite (TM
)become.
したがって、二次硬化は、炭化物の析出と冷却過程で変
態するマルテンサイト（ＦＭ）により生じている。Therefore, secondary hardening is caused by precipitation of carbides and martensite (FM) that transforms during the cooling process.
このように本発明の４００〜６００℃に焼戻したロール
の組織は、ＦＭ、ＴＭおよびγ５の３相から形成され、
１５０℃程度の低温焼戻しマルテンサイトとＴＲの従来
組織とは大きく異なり、基礎検討した結果本発明圧延ロ
ールの各相は大きく分類して、次のような性質を有して
いる。As described above, the structure of the roll tempered at 400 to 600°C of the present invention is formed from three phases of FM, TM and γ5,
It is greatly different from the conventional structure of martensite tempered at a low temperature of about 150° C. and TR, and as a result of basic studies, each phase of the rolling roll of the present invention can be broadly classified and has the following properties.
ごのなかで、Ｆ Ｍが主に耐摩耗性の向上および硬度確
保、ＴＭとＴ７が耐事故性向上させる相である。Among these, FM is the phase that mainly improves wear resistance and ensures hardness, and TM and T7 are the phases that improve accident resistance.
発明者はこれら相の構成比に着目し種々検討した結果、
ある範囲内におい゛ζ耐摩耗性および熱衝撃性が優れて
いることを見出した。As a result of various studies focusing on the composition ratio of these phases, the inventor found that
It has been found that the wear resistance and thermal shock resistance are excellent within a certain range.
次に各相の構成比限定理由について説明する。Next, the reason for limiting the composition ratio of each phase will be explained.
ＦＭ：５０〜８０％
ＦＭ量と熱衝撃クラック深さの関係を第１図に示す。Ｆ
Ｍ量が多くなるにつれてクラックは深くなる傾向が認め
られるが、従来の低温焼戻しロールよりはその深さは浅
い。ＦＭＪＩが５０％未満の領域ではその硬さはｌ−１
ｖ８００未満であり、冷間圧延用ロールとしての硬さを
満足することができず、さらに、耐摩耗性も低い。一方
、ＦＭが８０％を超えると硬さはＨν９００以−ヒと硬
（なり耐摩耗性は向上するが、逆に、圧延事故の際の欠
…（スポーリング）の危険性が高くなる。FM: 50-80% The relationship between the amount of FM and the depth of thermal shock cracks is shown in FIG. F
It is recognized that as the amount of M increases, the cracks tend to become deeper, but the depth is shallower than in conventional low temperature tempering rolls. In the region where FMJI is less than 50%, the hardness is l-1
v800, the hardness cannot be satisfied as a cold rolling roll, and furthermore, the wear resistance is low. On the other hand, when the FM exceeds 80%, the hardness becomes Hv900 or higher (the wear resistance improves, but conversely, the risk of spalling in the event of a rolling accident increases).
以上のことから、ＦＭ量は、５０〜８０％に限定した。Based on the above, the FM amount was limited to 50 to 80%.
ＴＭ：５０％以下
ＴＭ量の増加は、熱に対する材料の感受性を小さくする
とともに熱衝撃向上に寄与するが５０％超存在すると１
１ν８００の硬度が得られにくく、耐摩耗性の低下が大
きいので、ＴＭは５０％以下に限定した。TM: 50% or less An increase in the amount of TM reduces the sensitivity of the material to heat and contributes to improving thermal shock, but if it is present in excess of 50%, 1
Since it is difficult to obtain a hardness of 1v800 and the wear resistance is greatly reduced, TM was limited to 50% or less.
ｒ＊：ｔｓ％以下
Ｔ９の存在は、硬度を低下させる主な相であるとともに
経時的なマルテンサイト変態による寸法形状の変化、あ
るいは置き割れ、不均一摩耗（肌荒れ）、耐摩耗性の劣
化等からできるだけ少ないことが理想である。しかし、
熱衝撃性や靭性向上には極めて有効な相であることから
、その範囲は１５％以下に限定した。r*: ts% or less The presence of T9 is the main phase that reduces hardness, and also causes changes in size and shape due to martensitic transformation over time, cracking due to placement, uneven wear (rough skin), deterioration of wear resistance, etc. Ideally, it should be as small as possible. but,
Since it is an extremely effective phase for improving thermal shock resistance and toughness, its range was limited to 15% or less.
次に本発明のロールを構成する望ましい化学成分の割合
（重量比）について説明する。Next, the desirable ratio (weight ratio) of chemical components constituting the roll of the present invention will be explained.
Ｃ：０．５〜０．３ ｗｔ％
Ｃは、Ｃｒ、 Ｎｏ、■、Ｗなどの添加元素と共に炭化
物を形成し、耐摩耗性の向上に寄与する。また、焼入れ
過程においては、一部または全部基地中へ固溶し焼入れ
性を向上させる有効な元素である。C: 0.5 to 0.3 wt% C forms a carbide together with additive elements such as Cr, No, ■, W, etc., and contributes to improving wear resistance. Further, in the hardening process, it is an effective element that partially or completely dissolves into the matrix and improves the hardenability.
しかしながら、０．５ｗｔ％未満では焼入れ性に対して
不十分であり、０．８ｗｔ％を超えての添加は造塊時に
粗大な共晶状炭化物を晶出し、靭性を劣化させることか
ら適正なＣ範囲としては０．５〜０．８ｗｔ％が望まし
い。However, addition of less than 0.5 wt% is insufficient for hardenability, and addition of more than 0.8 wt% crystallizes coarse eutectic carbides during agglomeration, deteriorating toughness. A desirable range is 0.5 to 0.8 wt%.
Ｓｉ：０．５〜１．５賀（％
Ｓｉは、焼戻し軟化抵抗を高めるとももに溶解工程での
脱酸作用を有する。０．５％未満では、焼戻し軟化抵抗
に対して不十分であり、１．５％を超えての添加は、鋼
の脆化を助長する。よってＳｉは０．５〜１．５％の範
囲が望ましい。Si: 0.5 to 1.5% (% Si increases tempering softening resistance and also has a deoxidizing effect in the melting process. If it is less than 0.5%, it is insufficient for tempering softening resistance. Addition of more than 1.5% of Si promotes embrittlement of steel.Therefore, the content of Si is preferably in the range of 0.5 to 1.5%.
Ｍｎ ： ０．１〜１．０ｗｔ％
Ｍｎは、焼入れ性を向上させる元素である。０．１％未
満の添加は、焼入れ性に対して不十分であり、１０％を
超えての添加は焼入れ性に対して有効であるが鋼材の脆
化を助長することから０．１〜１．０％の範囲が望まし
い。Mn: 0.1 to 1.0 wt% Mn is an element that improves hardenability. Addition of less than 0.1% is insufficient for hardenability, and addition of more than 10% is effective for hardenability, but promotes embrittlement of the steel, so 0.1 to 1 A range of .0% is desirable.
Ｎｉ：０．１〜１．０ｗｔ％
Ｎｉは、特に高Ｃ鋼において基地中の固溶Ｃを減少させ
ず、焼入れ性の改善に有効な元素であることから、少な
くとも０．１％以上の添加が望ましい。Ni: 0.1 to 1.0 wt% Ni is an element that does not reduce solid solution C in the matrix and is effective in improving hardenability, especially in high C steel, so it is added at least 0.1% or more. is desirable.
一方、１％を超えての添加はオーステナイトを安定化し
、焼入れ状態での残留オーステナイト量を増加するとと
もに焼戻し処理後においてもオーステナイトを多量に残
存させることから目的とする硬さが得られない。そのた
めＮｉは０．１〜１．０％範囲が望ましい。On the other hand, addition of more than 1% stabilizes austenite, increases the amount of residual austenite in the hardened state, and causes a large amount of austenite to remain even after tempering, making it impossible to obtain the desired hardness. Therefore, Ni is preferably in the range of 0.1 to 1.0%.
Ｃｒ ： ３．０〜６．５ ｗｔ％
Ｃｒは、Ｍｏ、■、ＷとともにＣと結合し、複合炭化物
を形成し、耐摩耗性を向上させる有効な元素である。３
．０未満では耐摩耗性向上に対して不十分である。一方
、６．５％を超えての添加は炭化物を粗大化し、焼入れ
性を阻害することから、Ｃｒは３．０〜〇、５％が望ま
しい。Cr: 3.0 to 6.5 wt% Cr is an effective element that combines with C together with Mo, ■, and W to form a composite carbide and improve wear resistance. 3
．． If it is less than 0, the improvement in wear resistance is insufficient. On the other hand, since adding more than 6.5% coarsens carbides and impairs hardenability, it is desirable that Cr be in the range of 3.0 to 5%.
門ｏ：２．０〜５．ｆ１ｗｔ％
Ｍｏは、本発明の重要な元素の１つであり、一部は基地
中に固溶し焼入れ性を向上させるが、他はＣと結合して
、焼戻しの際、炭化物として析出することから二次硬化
に対して有効な元素であ、るとｋもに耐摩耗性を向上さ
せる。しかし、２．０％未満では、それらの効果が小さ
い、一方、５．０％を超えても、それらの効果は飽和す
ることから２．０〜５．０％の範囲が望ましい。Gate o: 2.0-5. f1wt% Mo is one of the important elements of the present invention, and some of it dissolves in solid solution in the matrix and improves hardenability, while others combine with C and precipitate as carbides during tempering. It is an effective element for secondary hardening, and it also improves wear resistance. However, if it is less than 2.0%, these effects are small, while if it exceeds 5.0%, these effects are saturated, so a range of 2.0 to 5.0% is desirable.
Ｖ： ２．１〜３．０ｗｔ％
■は、強い炭化物形成能を有し、硬質のＭＣ炭化物とし
て存在し、耐摩耗性を向上させるとともに、焼入れ加熱
時のオーステナイト粒の粗大化を抑制し、靭性を６１保
するために有効な元素である。V: 2.1 to 3.0 wt% ■ has a strong carbide forming ability, exists as a hard MC carbide, improves wear resistance, and suppresses coarsening of austenite grains during quenching heating, It is an effective element for maintaining toughness.
しかし、２．１％未満では、それらの効果が小さい。However, below 2.1%, these effects are small.
一方、３．０％を超えての添加は研削性を悪化するとと
もに炭化物を粗大化し、焼入れ性を阻害する。On the other hand, addition of more than 3.0% deteriorates grindability, coarsens carbides, and inhibits hardenability.
そのため、■の添加量は２．１〜３．０％が望ましい。Therefore, the amount of addition of (1) is preferably 2.1 to 3.0%.
Ｐ：≦０．０２０賀Ｌ％、Ｓ：≦０．Ｏ１０ｗｔ％Ｐお
よび８ついては、鋼の脆化を助長したり、介在物量を増
加さ〜ｌｊ、ｏ−ルのスポーリング発生を増大すること
から、極力抑える必要があり、Ｐは０．０２０％以下、
Ｓは０．０１０％以下が望ましい。P:≦0.020gL%, S:≦0. O10wt% P and 8 promote embrittlement of the steel, increase the amount of inclusions, and increase the occurrence of spalling in the steel, so it is necessary to suppress it as much as possible, and P is 0.020% or less. ,
Desirably, S is 0.010% or less.
さらに本発明では、これらの元素の他に、必要に応して
Ｗ、 Ｚｒ、 Ｔｉ、 Ｃｏ、 Ｎｂの一種または二種
以上を０．５〜３．０ｗｔ％添加することができる。こ
れらの元素は焼戻し後の硬さを増し、耐摩耗性向上に有
効である。その効果は０．５未満では殆んどなく、一方
、３％を超えて添加しても、飽和することから０．５〜
３．０％の範囲が望ましい。Furthermore, in the present invention, in addition to these elements, 0.5 to 3.0 wt% of one or more of W, Zr, Ti, Co, and Nb can be added as necessary. These elements increase hardness after tempering and are effective in improving wear resistance. There is almost no effect if it is less than 0.5%, and on the other hand, even if it is added in excess of 3%, it will be saturated, so 0.5~
A range of 3.0% is desirable.
次に本発明ロールの望ましい製造条件について説明する
。Next, desirable manufacturing conditions for the roll of the present invention will be explained.
本発明は、表面焼入れ後４００〜６００℃の範囲の比較
的高温の焼戻しを行うことが望ましく、これにより熱感
受性の小さい、しかも靭性の優れた組織を得ることがで
きる。In the present invention, it is desirable to perform tempering at a relatively high temperature in the range of 400 to 600° C. after surface hardening, whereby a structure with low thermal sensitivity and excellent toughness can be obtained.
しかし、当然４００〜６００℃の焼戻し後に少なくとも
Ｈｖ８００以上のロールとして最低限必要な硬さを確保
することが耐摩耗性および凹み傷対策として必要である
。However, as a matter of course, it is necessary to ensure a minimum hardness of Hv800 or more after tempering at 400 to 600°C as a measure against wear resistance and dents and scratches.
そのためには、４００〜６００℃の焼戻し中に微細な炭
化物を析出させることと、焼戻し処理において残留オー
ステナイトをマルテンサイトへ変態させることの２点を
積極的に利用することが重要である。For this purpose, it is important to actively utilize two points: precipitating fine carbides during tempering at 400 to 600°C, and transforming retained austenite into martensite during the tempering process.
そこで、成分調整され造塊された鋼塊を、鍛造、焼なら
しを含む均質化処理および調質処理後、焼入れ加熱温度
を１０５０〜＋２００’ｃの範囲に保ち、炭化物の７ト
リツクスへの固溶を促進させ、残留オーステナイト量を
５０％以上にすることが望ましい。Therefore, after the composition-adjusted and ingot-formed steel ingot is homogenized and tempered, including forging and normalizing, the quenching heating temperature is maintained in the range of 1050 to +200'c to harden the carbide into 7 trixes. It is desirable to accelerate dissolution and increase the amount of retained austenite to 50% or more.
焼入れ加熱温度が１０５０℃未満では、炭化物のマトリ
ンクスへの固溶が不十分であり、焼入れ状態での残留オ
ーステナイｉ・量が少ないので、４００〜６００℃の焼
戻し処理における炭化物の二次析出量が少なく、残留オ
ーステナイトのマルテンサイトへの変ｔＪｌも少なくな
ることから硬さの確保が困難である。一方、焼入れ時１
２００℃を超えての加熱は、部分的な溶融を生し、しか
も熱応力が多大となることから焼割れの危険性が高くな
ることから好ましくない。If the quenching heating temperature is less than 1050°C, the solid solution of carbides into the matrix is insufficient, and the amount of residual austenite in the quenched state is small, so the amount of secondary precipitation of carbides during tempering at 400 to 600°C is Since the change tJl of retained austenite to martensite also decreases, it is difficult to ensure hardness. On the other hand, during quenching 1
Heating above 200° C. is not preferable because it causes partial melting and increases thermal stress, increasing the risk of quench cracking.
次に焼戻し処理温度について説明する。Next, the tempering treatment temperature will be explained.
焼戻し処理では、焼入れで固溶させた炭化物を再び微細
析出さ−Ｕるごとと、残留オーステナイトをマルテンサ
イトへ変態させるごとにある。残留オーステナイトの量
は５０％以上が望ましく、これ未満では、次の４００〜
６００℃の焼戻しで、マルテンサイトに変態するオース
テナイト量が少なく、結果的に硬さが得られない。また
、望ましい焼戻し温度は４００〜６００℃であり、４０
０℃未満では圧延事故時の熱感受性の小さなロールが得
られず、また６００℃を紹えての焼戻し処理では、マル
テンサイトの分解が激しく、析出炭化物も凝集粗大化し
、所定の硬さが得られない。In the tempering treatment, the carbides dissolved in the solid solution during quenching are finely precipitated again, and the residual austenite is transformed into martensite. The amount of retained austenite is preferably 50% or more, and if it is less than 50%, the following 400~
When tempered at 600°C, the amount of austenite that transforms into martensite is small, resulting in no hardness. Further, the desirable tempering temperature is 400 to 600°C, and 40°C to 600°C.
If the temperature is lower than 0℃, it will not be possible to obtain a roll that is less sensitive to heat during rolling accidents, and if the temperature is tempered at 600℃, the martensite will be severely decomposed and the precipitated carbides will aggregate and coarsen, making it impossible to obtain the desired hardness. do not have.
次に実施例に基づいて本発明をより詳細に説明する。Next, the present invention will be explained in more detail based on examples.
〈実施例〉
表１に鋼塊（八〜Ｌ）の化学成分を示す。これらの鋼塊
を鍛造、球状化焼なましを含む前熱処理および軸部の強
度、靭性を付与するための調質処理後、表２に示す表面
焼入れ（１５０℃冷却停止）後焼戻し処理を行った。<Example> Table 1 shows the chemical composition of steel ingots (8 to L). These steel ingots were forged, and after pre-heat treatment including spheroidizing annealing and heat treatment to impart strength and toughness to the shaft, surface quenching (cooling stopped at 150°C) and tempering treatment as shown in Table 2 were performed. Ta.
材料試験としては、ビッカース硬さ、熱衝撃試験および
摩耗試験（２円筒式）を行った。As material tests, Vickers hardness, thermal shock tests, and abrasion tests (two-cylinder type) were conducted.
なお熱衝撃試験は、 １２０ｏｒｐｍのローラ（３４５
Ｃ）に荷Ｉｔ １１０ｋｇｆ 、接触時間１０ｓｅｃの
条件で試験片を押し当て、その際の熱ｔ９ｉ Ｍクラッ
ク濶さ（ｄ）で８７価した。The thermal shock test was conducted using a 120 orpm roller (345
A test piece was pressed against C) under the conditions of a load of 110 kgf and a contact time of 10 seconds, and the heat t9i M crack elongation (d) at that time was rated 87.
評価は、Ｏ：ｄ≦１＋ｎｍ △：ｌ鵬〈ｄ≦３ Ｘ：３＋ａｍ＜ｄ で行った。Evaluation is O: d≦1+nm △: lpeng〈d≦3 X:3+am<d I went there.
また摩耗試験は、接触応力２１０ｋｇｆ／ｌｊ、すべり
率１０％、相手材として中間ロール相当のロール材（Ｉ
ｌｖ ７００ ）を使用し、鉱油エマルジョン潤滑下で
、１０’回転後の摩耗深さ（大）で評価した。In addition, the wear test was conducted using a contact stress of 210 kgf/lj, a slip rate of 10%, and a roll material equivalent to an intermediate roll (I
lv 700), and the wear depth (large) after 10' rotation was evaluated under mineral oil emulsion lubrication.
評価は、○：ｔ≦２μｍ Δ：２μｍ＜１６５８ｍ ×：５μｍａｔ で行った。Evaluation: ○: t≦2μm Δ: 2μm<1658m ×: 5 μmat I went there.
これらの結果を表２に併せて示した。These results are also shown in Table 2.
これらの結果から、本発明のロールは、優れた耐摩耗性
とともに熱衝撃性を示すことが分かる。These results show that the roll of the present invention exhibits excellent abrasion resistance and thermal shock resistance.
一方、Ａ鋼の熱処理を望ましい範囲外で処理したロール
は組織相の構成比が本発明の範囲を外れ硬さ不足および
焼割れを生した。On the other hand, in the case of a roll in which steel A was heat-treated outside the desired range, the composition ratio of the microstructure was outside the range of the present invention, resulting in insufficient hardness and quench cracking.
さらに、Ａ鋼につい”ζ相構成比を変化して同様の実験
を行った結果を表３に示す。Furthermore, Table 3 shows the results of similar experiments conducted on steel A by changing the ζ phase composition ratio.
ＦＭ、ＴＭおよびＴ３が本請求範囲内であるＡＩ−Ａ−
５については、その範囲外の鋼（八−６〜Ａ−７）より
も優れた性能を持つことが確認できた。AI-A- where FM, TM and T3 are within the scope of this claim
Regarding No. 5, it was confirmed that it had better performance than the steels (8-6 to A-7) outside the range.
〈発明の効果〉
本発明により、優れた耐事故性および耐摩耗性を有する
ロールが圧延に提供できるようになった。<Effects of the Invention> According to the present invention, a roll having excellent accident resistance and wear resistance can be provided for rolling.
これにより通常圧延時のロール原単位の向上および圧延
事故の際のロール原単位の悪化を最小限に抑えることが
可能となり、全体的なロール原単位の向上が回持てきる
。This makes it possible to improve the roll consumption rate during normal rolling and to minimize the deterioration of the roll consumption rate in the event of a rolling accident, thereby making it possible to improve the overall roll consumption rate.
第１図はＦＭと熱衝撃クラック深さの関係を示すグラフ
である。
ＦＭ量（％）FIG. 1 is a graph showing the relationship between FM and thermal shock crack depth. FM amount (%)
Claims (1)
ルの組織構成が、焼戻し時の冷却過程でオーステナイト
からマルテンサイトへ変態した相５０〜８０％、焼戻し
マルテンサイト相５０％以下、残部が実質的に１５％以
下の残留オーステナイト相からなることを特徴とする耐
摩耗性および熱衝撃性に優れた鍛鋼製圧延ロール。 ２、高炭素合金鋼が、Ｃ：０．５〜０．８ｗｔ％、Ｓｉ
：０．５〜１．５ｗｔ％、Ｍｎ：０．１〜１．０ｗｔ％
、Ｎｉ：０．１〜１．０ｗｔ％、Ｃｒ：３．０〜６．５
ｗｔ％、Ｍｏ：２．０〜５．０ｗｔ％、Ｖ：２．１〜３
．０ｗｔ％、Ｐ：０．０２０ｗｔ％以下、Ｓ：０．０１
０ｗｔ％以下を含有し、残部がＦｅおよび不可避的不純
物よりなる鋼であることを特徴とする請求項１記載の耐
摩耗性および熱衝撃性に優れた鍛鋼製圧延ロール。 ３、高炭素合金鋼が、Ｃ：０．５〜０．８ｗｔ％、Ｓｉ
：０．５〜１．５ｗｔ％、Ｍｎ：０．１〜１．０ｗｔ％
、Ｎｉ：０．１〜１．０ｗｔ％、Ｃｒ：３．０〜６．５
ｗｔ％、Ｍｏ：２．０〜５．０ｗｔ％、Ｖ：２．１〜３
．０ｗｔ％、Ｐ：０．０２０ｗｔ％以下、Ｓ：０．０１
０ｗｔ％以下およびＷ、Ｚｒ、Ｔｉ、Ｃｏ、Ｎｂの１種
または２種以上を合計で０．５〜３．０ｗｔ％含有し、
残部がＦｅおよび不可避的不純物よりなる鋼であること
を特徴とする請求項１記載の耐摩耗性および熱衝撃性に
優れた鍛鋼製圧延ロール。 ４、Ｃ：０．５〜０．８ｗｔ％、Ｓｉ：０．５〜１．５
ｗｔ％、Ｍｎ：０．１〜１．０ｗｔ％、Ｎｉ：０．１〜
１．０ｗｔ％、Ｃｒ：３．０〜６．５ｗｔ％、Ｍｏ：２
．０〜５．０ｗｔ％、Ｖ：２．１〜３．０ｗｔ％、Ｐ：
０．０２０ｗｔ％以下、Ｓ：０．０１０ｗｔ％以下を含
有し、残部がＦｅおよび不可避的不純物よりなる素材を
１０５０〜１２００℃の温度に加熱、強制冷却を行い、
残留オーステナイトが５０％以上となる組織とした後、
４００〜６００℃の温度で焼戻しを行うことを特徴とす
る耐摩耗性および熱衝撃性に優れた鍛鋼製圧延ロールの
製造方法。 ５、Ｃ：０．５〜０．８ｗｔ％、Ｓｉ：０．５〜１．５
ｗｔ％、Ｍｎ：０．１〜１．０ｗｔ％、Ｎｉ：０．１〜
１．０ｗｔ％、Ｃｒ：３．０〜６．５ｗｔ％、Ｍｏ：２
．０〜５．０ｗｔ％、Ｖ：２．１〜３．０ｗｔ％、Ｐ：
０．０２０ｗｔ％以下、Ｓ：０．０１０ｗｔ％以下およ
びＷ、Ｚｒ、Ｔｉ、Ｃｏ、Ｎｂの１種または２種以上を
合計で０．２〜３．０ｗｔ％含有し、残部がＦｅおよび
不可避的不純物よりなる素材を１０５０〜１２００℃の
温度に加熱、強制冷却を行い、残留オーステナイトが５
０％以上となる組織とした後、４００〜６００℃の温度
で焼戻しを行うことを特徴とする耐摩耗性および熱衝撃
性に優れた鍛鋼製圧延ロールの製造方法。[Scope of Claims] 1. The structure of the forged steel quenched and tempered rolling roll made of high carbon alloy steel is 50 to 80% of the phase transformed from austenite to martensite during the cooling process during tempering, and 50% of the tempered martensite phase. Hereinafter, a forged steel rolling roll having excellent wear resistance and thermal shock resistance is characterized in that the remainder is substantially 15% or less of retained austenite phase. 2. High carbon alloy steel contains C: 0.5 to 0.8 wt%, Si
:0.5-1.5wt%, Mn:0.1-1.0wt%
, Ni: 0.1 to 1.0 wt%, Cr: 3.0 to 6.5
wt%, Mo: 2.0 to 5.0 wt%, V: 2.1 to 3
．． 0wt%, P: 0.020wt% or less, S: 0.01
2. The forged steel rolling roll with excellent wear resistance and thermal shock resistance according to claim 1, characterized in that the steel contains 0 wt% or less, with the remainder consisting of Fe and unavoidable impurities. 3. High carbon alloy steel contains C: 0.5 to 0.8 wt%, Si
:0.5-1.5wt%, Mn:0.1-1.0wt%
, Ni: 0.1 to 1.0 wt%, Cr: 3.0 to 6.5
wt%, Mo: 2.0 to 5.0 wt%, V: 2.1 to 3
．． 0wt%, P: 0.020wt% or less, S: 0.01
0 wt% or less and a total of 0.5 to 3.0 wt% of one or more of W, Zr, Ti, Co, and Nb,
2. The forged steel rolling roll with excellent wear resistance and thermal shock resistance according to claim 1, wherein the remainder is made of steel consisting of Fe and unavoidable impurities. 4, C: 0.5-0.8wt%, Si: 0.5-1.5
wt%, Mn: 0.1 to 1.0 wt%, Ni: 0.1 to
1.0wt%, Cr:3.0-6.5wt%, Mo:2
．． 0 to 5.0 wt%, V: 2.1 to 3.0 wt%, P:
A material containing 0.020 wt% or less, S: 0.010 wt% or less, and the remainder consisting of Fe and unavoidable impurities is heated to a temperature of 1050 to 1200 ° C. and forcedly cooled,
After creating a structure with retained austenite of 50% or more,
A method for manufacturing a forged steel rolling roll with excellent wear resistance and thermal shock resistance, characterized by tempering at a temperature of 400 to 600°C. 5, C: 0.5-0.8wt%, Si: 0.5-1.5
wt%, Mn: 0.1 to 1.0 wt%, Ni: 0.1 to
1.0wt%, Cr:3.0-6.5wt%, Mo:2
．． 0 to 5.0 wt%, V: 2.1 to 3.0 wt%, P:
0.020wt% or less, S: 0.010wt% or less, and a total of 0.2 to 3.0wt% of one or more of W, Zr, Ti, Co, and Nb, with the balance being Fe and unavoidable The material consisting of impurities is heated to a temperature of 1050 to 1200°C and forcedly cooled to reduce residual austenite to 5.
A method for manufacturing a forged steel rolling roll with excellent wear resistance and thermal shock resistance, which comprises forming a structure with a structure of 0% or more and then tempering at a temperature of 400 to 600°C.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25774589 | 1989-10-04 | ||
| JP1-257745 | 1989-10-04 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03219048A true JPH03219048A (en) | 1991-09-26 |
Family
ID=17310513
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22100190A Pending JPH03219048A (en) | 1989-10-04 | 1990-08-24 | Rolling roll made of forged steel excellent in wear resistance and thermal shock properties and its manufacture |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03219048A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0869196A2 (en) * | 1997-03-31 | 1998-10-07 | Daido Tokushuko Kabushiki Kaisha | Cast cold tool and method for producing the same |
| EP2495340A1 (en) * | 2011-03-04 | 2012-09-05 | Akers AB | A forged roll meeting the requirements of the cold rolling industry and a method for production of such a roll |
| US8920296B2 (en) | 2011-03-04 | 2014-12-30 | Åkers AB | Forged roll meeting the requirements of the cold rolling industry and a method for production of such a roll |
| SE2050705A1 (en) * | 2020-06-12 | 2021-12-13 | Uddeholms Ab | Hot work tool steel |
| SE2251369A1 (en) * | 2022-11-23 | 2024-05-24 | Erasteel Kloster Ab | A powder metallurgical tool steel |
-
1990
- 1990-08-24 JP JP22100190A patent/JPH03219048A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0869196A2 (en) * | 1997-03-31 | 1998-10-07 | Daido Tokushuko Kabushiki Kaisha | Cast cold tool and method for producing the same |
| EP0869196A3 (en) * | 1997-03-31 | 2001-10-04 | Daido Tokushuko Kabushiki Kaisha | Cast cold tool and method for producing the same |
| EP2495340A1 (en) * | 2011-03-04 | 2012-09-05 | Akers AB | A forged roll meeting the requirements of the cold rolling industry and a method for production of such a roll |
| US8920296B2 (en) | 2011-03-04 | 2014-12-30 | Åkers AB | Forged roll meeting the requirements of the cold rolling industry and a method for production of such a roll |
| SE2050705A1 (en) * | 2020-06-12 | 2021-12-13 | Uddeholms Ab | Hot work tool steel |
| SE544123C2 (en) * | 2020-06-12 | 2022-01-04 | Uddeholms Ab | Hot work tool steel |
| SE2251369A1 (en) * | 2022-11-23 | 2024-05-24 | Erasteel Kloster Ab | A powder metallurgical tool steel |
| WO2024110302A1 (en) * | 2022-11-23 | 2024-05-30 | Erasteel Kloster Ab | A powder metallurgical tool steel |
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