JP2778765B2 - Wear resistant composite roll - Google Patents
Wear resistant composite rollInfo
- Publication number
- JP2778765B2 JP2778765B2 JP1311419A JP31141989A JP2778765B2 JP 2778765 B2 JP2778765 B2 JP 2778765B2 JP 1311419 A JP1311419 A JP 1311419A JP 31141989 A JP31141989 A JP 31141989A JP 2778765 B2 JP2778765 B2 JP 2778765B2
- Authority
- JP
- Japan
- Prior art keywords
- inner layer
- wear
- composite roll
- outer shell
- 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.)
- Expired - Lifetime
Links
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- Reduction Rolling/Reduction Stand/Operation Of Reduction Machine (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は耐摩耗性に優れた熱間あるいは冷間圧延用ロ
ールに関するものである。Description: TECHNICAL FIELD The present invention relates to a roll for hot or cold rolling having excellent wear resistance.
熱間あるいは冷間圧延用ロールは、耐摩耗性と強靭性
とを同時に有することが必要であるため、遠心鋳造法に
より外殻層と内層とが複合化したロールとし、外殻層に
耐摩耗性のある材料を用い、内層に強靭性を有する材料
を用いることが広く行われている。この複合ロールは、
高速で回転している遠心鋳造金型内に外殻層となる溶湯
を鋳込んで中空の外殻層を形成し、形成された外殻層内
に内層となる溶湯を注入することにより製造することが
できる。このようにして、外殻層と内層が金属接合した
複合ロールが得られるが、このとき内層溶湯の熱量によ
り外殻層内面の一部が再溶融し、内層と共に再凝固す
る。Rolls for hot or cold rolling need to have both abrasion resistance and toughness at the same time.Therefore, rolls in which the outer shell layer and inner layer are combined by centrifugal casting are used. It is widely practiced to use a material having a property and a material having toughness for an inner layer. This composite role
A hollow outer shell layer is formed by casting a molten metal serving as an outer shell layer into a centrifugal casting mold rotating at a high speed, and is manufactured by injecting the molten metal serving as an inner layer into the formed outer shell layer. be able to. In this way, a composite roll in which the outer shell layer and the inner layer are metal-bonded is obtained. At this time, a part of the inner surface of the outer shell layer is re-melted due to the heat of the inner layer molten metal, and is re-solidified together with the inner layer.
このような遠心鋳造複合ロールの外殻層は硬質の炭化
物を晶出させれ耐摩耗性を得るのが最も有効である。こ
のようなロールの外殻層材質として、例えばIron and S
teel Engineer,April 1979、第42頁〜第49頁に開示され
ているように、硬質のCr炭化物を多く含有する高クロム
鋳鉄が広く用いられている。It is most effective for the outer shell layer of such a centrifugally cast composite roll to crystallize hard carbide and obtain abrasion resistance. As a material for the outer layer of such a roll, for example, Iron and S
As disclosed in Steel Engineer, April 1979, pp. 42-49, high chromium cast iron containing a large amount of hard Cr carbide is widely used.
高クロム鋳鉄より更に耐摩耗性を向上させる方法とし
て、Cr炭化物より更に硬質の炭化物を形成するＶ、Ｗ、
Moなどを多量に添加する方法が考えられるが、このよう
な材質の遠心鋳造複合ロールは次の理由で製造できなか
った。As a method of improving the wear resistance further than high chromium cast iron, V, W, which forms a harder carbide than Cr carbide,
Although a method of adding a large amount of Mo or the like is conceivable, a centrifugally cast composite roll made of such a material cannot be manufactured for the following reasons.
まず、Ｖは耐摩耗性に極めて有効な硬質VC炭化物を形
成するが、この炭化物の比重は小さく、溶湯との比重差
が大きいため遠心鋳造時に内面側に濃縮する傾向を有す
る。このためロール使用表層部のＣおよびＶ量が著しく
減少する。First, V forms a hard VC carbide which is extremely effective in abrasion resistance. However, since the specific gravity of this carbide is small and the difference in specific gravity with the molten metal is large, it tends to concentrate on the inner surface side during centrifugal casting. For this reason, the C and V contents in the surface layer of the roll are significantly reduced.
次に、硬質炭化物を形成するＶ、Ｗ、Mo等は強い白銑
化元素であり、外殻層と内層の溶着時に内層鋳鉄あるい
は鋳鋼に混入し、内層が鋳鉄の場合はその黒鉛化を著し
く劣化させる。このため、内層が脆化し、製造中或いは
圧延使用中に胴折れを生じる原因となる。Next, V, W, Mo, etc. that form hard carbides are strong white iron elements, and are mixed into the inner cast iron or cast steel at the time of welding the outer shell layer and the inner layer, and when the inner layer is cast iron, its graphitization is remarkable. Deteriorate. For this reason, the inner layer is embrittled, which causes the body to break during manufacturing or rolling use.
さらに、内層に黒鉛や炭化物の晶出しない鋼を用いた
場合、白銑化元素が混入することによる内層材の脆化の
問題はないが、内層の方が外殻層より高融点となるた
め、内層を注入した時に外殻層が溶けて、混合状態とな
った境界部分が最終凝固層となり、この境界部に鋳造欠
陥が発生しやすいという問題がある。Furthermore, when using steel that does not crystallize graphite or carbide in the inner layer, there is no problem of embrittlement of the inner layer material due to the incorporation of elemental white iron, but the inner layer has a higher melting point than the outer shell layer However, when the inner layer is injected, the outer shell layer is melted, and the boundary portion in the mixed state becomes a final solidified layer, and there is a problem that casting defects easily occur at this boundary portion.
従って、本発明の目的は、V,Mo,W等の硬質炭化物が均
一に分布した外殻層と、黒鉛化の良好な鋳鉄或いは鋳鋼
からなる内層が溶着一体化した、耐摩耗性の極めて良好
な複合ロールを得ようとするものである。Accordingly, an object of the present invention is to provide an extremely excellent wear resistance in which an outer shell layer in which hard carbides such as V, Mo, and W are uniformly distributed and an inner layer made of cast iron or cast steel having good graphitization are welded and integrated. It is intended to obtain a complex composite roll.
VCをはじめとする硬質炭化物を含有する遠心鋳造複合
ロールを製造する際の第一の問題点は、溶湯との比重が
相違するVC炭化物が遠心分離することである。この問題
点につき発明者は種々の実験を行った結果、VC炭化物を
遠心分離による偏析程度は、VC炭化物を初晶での晶出が
少ない化学組成であれば極く小さいものであることを見
い出した。つまり、重量比で、C1〜４％,Si3％以下,Mn
1.5％以下,Ni4％以下,Cr3.01〜8.21％,Mo8％以下,W20％
以下,V4.66〜10％、残部実質的にFe及び不純物元素から
なるとともに、Ｃ％＋0.4V％の値が6.0以下の組成範囲
とすれば、初晶としてVC炭化物がほとんど晶出しないた
め、VC炭化物の内側部分での偏析が少なく、かつ耐摩耗
性の良好な外殻層材を得ることができる。The first problem in producing a centrifugally cast composite roll containing a hard carbide such as VC is that VC carbide having a specific gravity different from that of a molten metal is centrifuged. The inventor conducted various experiments on this problem and found that the degree of segregation of VC carbide by centrifugation was extremely small if the chemical composition of VC carbide was low in primary crystals. Was. That is, by weight ratio, C1-4%, Si3% or less, Mn
1.5% or less, Ni4% or less, Cr3.01 to 8.21%, Mo8% or less, W20%
Below, V4.66-10%, the balance is substantially composed of Fe and impurity elements, and if the value of C% + 0.4V% is within the composition range of 6.0 or less, VC carbides hardly crystallize as primary crystals. In addition, it is possible to obtain an outer shell layer material having less segregation in the inner portion of the VC carbide and having good wear resistance.
従って、本発明の耐摩耗複合ロールは、遠心鋳造方に
より鋳造した外殻層と鋳鉄又は鋳鋼の内層材とが溶着一
体化したもので、外殻層の化学成分が重量比でC1〜４
％、Si3％以下、Mn1.5％以下、Ni4％以下、Cr3.01〜8.2
1％、Mo8％以下、W20％以下、V4.66〜10％、残部実質的
にFe及び不可避的不純物元素からなるとともに、Ｃ％＋
0.4V％の値が6.0以下であることを特徴とする。Therefore, the wear-resistant composite roll of the present invention is obtained by integrating the outer shell layer cast by the centrifugal casting method with the inner layer material of cast iron or cast steel, and the chemical composition of the outer shell layer is C1-4 by weight ratio.
%, Si 3% or less, Mn 1.5% or less, Ni 4% or less, Cr 3.01 to 8.2
1%, Mo 8% or less, W 20% or less, V4.66-10%, balance substantially consists of Fe and unavoidable impurity elements, and C% +
The value of 0.4 V% is 6.0 or less.
本発明を以下詳細に説明する。 The present invention will be described in detail below.
以下に各元素の含有量（重量比）の特定理由を述べ
る。The specific reasons for the content (weight ratio) of each element will be described below.
（ａ）C:1〜４％ Ｃは耐摩耗性の向上に必要な炭化物を構成する元素で
ある。１％未満では炭化物量が十分でなく、十分な耐摩
耗性が得られない。一方、Ｃ量を多くすると、初晶VC炭
化物の晶出する量が過多となるので制限される。この量
はＶ量によっても制限を受けるが、Ｃが４％を超えると
いずれのＶ量の場合にも初晶において炭化物を晶出が過
多となり、鋳造の際にVC炭化物の著しい偏析が生じるの
で不都合である。(A) C: 1 to 4% C is an element constituting carbide necessary for improving wear resistance. If it is less than 1%, the amount of carbide is not sufficient, and sufficient wear resistance cannot be obtained. On the other hand, if the amount of C is increased, the amount of the primary crystal VC carbide to be crystallized becomes excessive, so that the amount is limited. This amount is also limited by the amount of V, but if C exceeds 4%, the carbides are excessively crystallized in the primary crystal at any V amount, and remarkable segregation of VC carbide occurs during casting. It is inconvenient.
（ｂ）Si:3％以下 Siは脱酸剤として有効であるが、３％を超えると材質
的に脆化するため不都合である。(B) Si: 3% or less Si is effective as a deoxidizing agent, but if it exceeds 3%, it is disadvantageous because the material becomes brittle.
（ｃ）Mn:1.5％以下 MnもSiと同様脱酸剤であるが、ＳをMnSとして固定す
る作用もある。しかし1.5％を超えると材質が脆化する
ため不都合である。(C) Mn: 1.5% or less Mn is a deoxidizing agent like Si, but also has the effect of fixing S as MnS. However, if it exceeds 1.5%, the material becomes brittle, which is inconvenient.
（ｄ）Ni:4％以下 Niはオーステナイトを安定化させ、焼入性を良好にす
るため、大型ロールの製造の場合に添加すると有効であ
る。しかし、４％を超えるとオーステナイトが安定化し
すぎ、残留オーステナイトの分解が困難となるため、硬
さや耐摩耗性が十分得られなくなる。(D) Ni: 4% or less Ni is effective to stabilize austenite and improve hardenability, when it is added in the case of manufacturing large rolls. However, when the content exceeds 4%, austenite is excessively stabilized, and it becomes difficult to decompose retained austenite, so that sufficient hardness and wear resistance cannot be obtained.
（ｅ）Cr:3.01〜8.21％ Crは焼入性向上及び硬質のM7C3系炭化物を形成するた
め添加する。Crが3.01％未満ではその添加による効果が
十分でない。また8.21％を超えると、より硬質のVC炭化
物の量が少なくなりすぎるため、Cr量は8.21％以下とす
る。(E) Cr: 3.01~8.21% Cr is added to form a M 7 C 3 carbide hardenability enhancement and hard. If Cr is less than 3.01%, the effect of the addition is not sufficient. On the other hand, if it exceeds 8.21%, the amount of harder VC carbides becomes too small, so the Cr content is set to 8.21% or less.
（ｆ）Mo:8％以下 Moは焼入性向上及び焼戻し硬さ向上のため添加する。
しかし、８％を超えて添加すると、M2C系あるいはM6C系
炭化物の晶出が多くなり、より硬質のVCが減少する。(F) Mo: 8% or less Mo is added for improving hardenability and tempering hardness.
However, if added in excess of 8%, the crystallization of M 2 C-based or M 6 C-based carbides increases, and the harder VC decreases.
（ｇ）W:20％以下 Ｗは焼戻し硬さ向上の作用があるとともに、VC炭化物
中に置換固溶し、VC炭化物の比重を増加し、重力偏析程
度を軽減する作用を持つ。しかし、20％を越えて添加す
るとW6C炭化物が多く晶出し、より硬質のVC炭化物が減
少する。(G) W: 20% or less W has the effect of improving the tempering hardness, and has the effect of dissolving in VC carbides to increase the specific gravity of VC carbides and reduce the degree of gravity segregation. However, if it is added in excess of 20%, a large amount of W 6 C carbides are crystallized, and harder VC carbides are reduced.
（ｈ）V:4.66〜10％ Ｖは本発明の複合ロールの耐摩耗性に最も寄与する元
素である。つまり、Ｖは非常に炭化物形成作用の強い元
素であり、硬質のVCを形成する。このＶが4.66％未満で
は、VC炭化物の晶出が十分ではない。一方Ｖの含有量が
多すぎると、初晶の粒状VC炭化物が過多となり、遠心鋳
造時の遠心力によって比重の軽いVC炭化物が内側部分に
偏析する。従ってＶの含有量は10％以下にする必要があ
る。(H) V: 4.66 to 10% V is an element that most contributes to the wear resistance of the composite roll of the present invention. That is, V is an element having a very strong carbide-forming action, and forms a hard VC. If this V is less than 4.66%, crystallization of VC carbide is not sufficient. On the other hand, when the content of V is too large, the amount of primary crystal VC carbide becomes excessive, and the VC carbide having a low specific gravity segregates in the inner portion due to centrifugal force during centrifugal casting. Therefore, the V content needs to be 10% or less.
またこのようなＶ量は、主としてＣ量によって制限さ
れる。本発明者は種々実験を重ねることにより、このよ
うな初晶VC炭化物の晶出が少なく、遠心鋳造での偏析が
問題とならない組成範囲を求めた。すなわち、重量比に
て、Ｃ％＋0.4V％が6.0以下となるような組成であれ
ば、初晶でのVC炭化物の晶出が十分少なくなる。従っ
て、このような組成範囲であれば遠心鋳造によって外殻
層を鋳造しても、外殻層内面側へのＶやＣの偏析が少な
く、ほぼ均一な組成の外殻層を形成することができる。Such V amount is mainly limited by the C amount. The present inventor has conducted various experiments to find a composition range in which the crystallization of such primary VC carbides is small and segregation in centrifugal casting does not pose a problem. That is, if the composition is such that the weight ratio of C% + 0.4V% is 6.0 or less, the crystallization of VC carbide in the primary crystal is sufficiently reduced. Therefore, if the outer shell layer is cast by centrifugal casting in such a composition range, segregation of V and C on the inner surface side of the outer shell layer is small, and an outer shell layer having a substantially uniform composition can be formed. it can.
（ｉ）その他の化学成分 また本発明においては、上記した成分に加えて、さら
にTi、Zr及びNbのうちの少なくとも１種を外殻層に加え
てもよい。Ti、Zr及びNbは、Ｖと同様に硬質炭化物を形
成する元素であり、これらをロールの外殻層に導入する
ことで、耐摩耗性の向上を図ることができる。Ti、Zr及
びNbの１種又は２種以上の成分の配合割合は、合計で５
％以下とする。これらの元素の合計が５％を超える量と
すると、VC炭化物の量が少なくなりすぎるため好ましく
ない。(I) Other Chemical Components In the present invention, in addition to the above components, at least one of Ti, Zr, and Nb may be further added to the outer shell layer. Ti, Zr and Nb are elements forming hard carbides like V, and by introducing them into the outer shell layer of the roll, the wear resistance can be improved. The mixing ratio of one or more components of Ti, Zr and Nb is 5 in total.
% Or less. If the total amount of these elements exceeds 5%, the amount of VC carbide becomes too small, which is not preferable.
さらに、本発明ではCoを外殻層の成分として加えても
よい。Coはロール基地に固溶し、ロールの熱間強度を向
上させる作用を有する。従って、Coの添加は、特に熱間
圧延用ロールの耐摩耗性、耐肌あれ性の向上に有効であ
る。この効果はCoの添加量が15％であれば十分であり、
また15％を超えても耐摩耗性及び耐肌あれ性の向上が特
にみられないので、経済性の点から15％以下とする。Further, in the present invention, Co may be added as a component of the outer shell layer. Co forms a solid solution in the roll base and has an effect of improving the hot strength of the roll. Therefore, the addition of Co is particularly effective for improving the abrasion resistance and the roughening resistance of the hot rolling roll. This effect is sufficient if the amount of Co added is 15%.
Further, even if it exceeds 15%, no improvement in abrasion resistance and rough skin resistance is particularly observed.
上述の組成の外殻層を用い、内層が黒鉛を晶出するね
ずみ鋳鉄、ダクタイル鋳鉄、黒鉛鋼等の材質である複合
ロールを製造する際、問題となるのは、外殻層と内層の
溶着時にV,W,Moなどの強力な白銑化元素が内層に混入す
ることにともなう内層の白銑化による脆化である。この
問題について、本発明者は、種々実験検討し、次の方法
で解決できることを見出した。When manufacturing a composite roll made of a material such as gray cast iron, ductile cast iron, or graphite steel in which the inner layer crystallizes graphite using the outer shell layer having the above composition, the problem is the welding of the outer shell layer and the inner layer. It is embrittlement due to whitening of the inner layer, sometimes due to the incorporation of strong whitening elements such as V, W, and Mo into the inner layer. The present inventor has conducted various experimental studies on this problem and found that it can be solved by the following method.
まず、外殻層を鋳込んでから内層を鋳込むまでの時
間、内層の鋳込み温度、内層の成分及び溶湯処理等の各
条件を適切に選択することによって外殻層と内層との溶
着時の外殻層内面の溶解量が少なく、その結果内層へ混
入する白銑化元素を十分低位に抑えることが可能であ
る。First, the time from the casting of the outer shell layer to the casting of the inner layer, the casting temperature of the inner layer, the components of the inner layer and the conditions of the molten metal treatment, etc. The amount of dissolution on the inner surface of the outer shell layer is small, and as a result, the amount of white iron turning element mixed into the inner layer can be sufficiently suppressed.
次に、上記手法は各条件の管理幅が狭く、成分、寸法
が異なる時の条件設定に手間がかかるが、さらに外殻層
を鋳込んだ後、重量比で２％以下のＣを含む鋳鋼を鋳込
み、その後内層剤となるねずみ鋳鉄、ダクタイル鋳鉄、
黒鉛鋼等を鋳込むことにより、内層への白銑化元素の混
入を比較的容易に低位に抑えることができる。Next, in the above method, the control range of each condition is narrow, and it takes time to set the conditions when the components and dimensions are different, but after further casting the outer shell layer, the cast steel containing C of 2% or less by weight ratio is used. , Then gray cast iron, ductile cast iron,
By casting graphite steel or the like, it is possible to relatively easily suppress the incorporation of an element for forming white iron into the inner layer to a low level.
さらにまた、上述のような外殻層を用い、内層が鋳鋼
である複合ロールを製造する際は、前述のような内層の
脆化の問題はないが、境界に鋳造欠陥が発生し易いとい
う問題があった。この問題について種々実験検討した結
果、外殻層を鋳込んでから内層を鋳込むまでの時間、内
層の鋳込温度、内層の成分及び溶湯処理等の各条件を適
切に選択し、かつ鋳型の形状、冷却能力を適切に設定す
ることにより内層に鋼を用いても境界欠陥の発生を防ぐ
ことが可能となった。Furthermore, when manufacturing a composite roll in which the inner layer is cast steel using the outer shell layer as described above, there is no problem of embrittlement of the inner layer as described above, but a problem that casting defects are likely to occur at the boundary. was there. As a result of various experiments and examinations on this problem, the time from casting the outer shell layer to casting the inner layer, the casting temperature of the inner layer, the components of the inner layer, and the conditions of the molten metal treatment, etc. were appropriately selected, and By appropriately setting the shape and cooling capacity, it became possible to prevent the occurrence of boundary defects even when steel was used for the inner layer.
本発明を更に以下の実施例により詳細に説明する。 The present invention is further described in detail by the following examples.
実施例１ 第１表に示す組成の外層用溶湯を直径70mm、高さ80mm
のCO2砂型に注入して、圧延摩耗試験用の小型ロール素
材を鋳造した。この素材に1000〜1100℃からの焼入れ及
び500〜550℃での焼戻しの熱処理を施した後、外径60m
m、内径35mm、長さ40mmのスリーブ状の試験用ロールを
作成した。Example 1 An outer layer molten metal having a composition shown in Table 1 was 70 mm in diameter and 80 mm in height.
Into a CO 2 sand mold to cast a small roll material for a rolling wear test. After the material is subjected to heat treatment of quenching from 1000 to 1100 ° C and tempering at 500 to 550 ° C, the outer diameter is 60m
A sleeve-shaped test roll having a length of m, an inner diameter of 35 mm and a length of 40 mm was prepared.
各試験用ロールの外殻層表面の硬さをショアー硬さ計
により測定した結果を第２表に示す。次にこの試験用ロ
ールの圧延摩耗試験を行った。圧延摩耗試験機は第５図
に示す通り、圧延機１と、圧延機１に組み込まれた上ロ
ール２及び下ロール３と、圧延材Ｓを予熱する加熱炉４
と、圧延材Ｓを冷却する冷却水槽５と、圧延中に一定の
テンションを与える巻取機６と、テンションを調節する
テンションコントローラ７とからなる。試験条件は以下
の通りであった。Table 2 shows the results obtained by measuring the hardness of the outer shell layer surface of each test roll with a Shore hardness tester. Next, a rolling wear test of this test roll was performed. As shown in FIG. 5, the rolling wear tester includes a rolling mill 1, an upper roll 2 and a lower roll 3 incorporated in the rolling mill 1, and a heating furnace 4 for preheating the rolled material S.
A cooling water tank 5 for cooling the rolled material S, a winding machine 6 for applying a constant tension during rolling, and a tension controller 7 for adjusting the tension. The test conditions were as follows.
圧延材 :SUS 304、厚さ1mm、幅15mm 圧延距離 :800m 圧延温度 :900℃ 圧下率 :25％ 圧延速度 :150m/分 ロール冷却：水 冷 試験用ロールの表面に生じた摩耗の深さを触針式表面
荒さ計（SURFCOM）を用いて測定した。得られた結果を
サンプルNo.1について第３図Ａに示す。また各ロールに
ついて摩耗深さを圧延幅において平均して平均摩耗深さ
を求めた結果を第２表に示す。Rolled material: SUS 304, thickness 1mm, width 15mm Rolling distance: 800m Rolling temperature: 900 ° C Rolling rate: 25% Rolling speed: 150m / min Roll cooling: water cooling Determine the depth of wear generated on the surface of the test roll. It was measured using a stylus type surface roughness meter (SURFCOM). The results obtained are shown in FIG. 3A for sample No. 1. Table 2 shows the average wear depth obtained by averaging the wear depth of each roll in the rolling width.
比較用の従来の材質としては、高クロム鋳鉄（従来例
１）及び合金グレンロール材（従来例２）について実施
例１と同様にして試験用ロールを作製した。ただし、熱
処理はこれらの材質に適応した熱処理を施した。実施例
１と同様にして摩耗試験を行い、摩耗深さの実測値をそ
れぞれ第３図Ｂ（従来例１）及びＣ（従来例２）に示
す。また硬さを測定した結果を第２表に示す。As a conventional material for comparison, a test roll was produced in the same manner as in Example 1 for a high chromium cast iron (conventional example 1) and an alloy grain roll material (conventional example 2). However, the heat treatment was performed according to these materials. A wear test was performed in the same manner as in Example 1, and measured values of the wear depth are shown in FIGS. 3B (conventional example 1) and C (conventional example 2), respectively. Table 2 shows the results of measuring the hardness.
実施例２ 第３表に示す化学成分の本発明材（ａ）及び従来材
（ｂ）を鋳型内径450mmφ、胴長750mmの金型を用いて遠
心鋳造し、肉厚60mmのスリーブロールを製造した。回転
数はスリーブロール内面の遠心力が140Gとなるよう設定
した。 Example 2 The present invention material (a) and the conventional material (b) having the chemical components shown in Table 3 were centrifugally cast using a mold having a mold inner diameter of 450 mmφ and a body length of 750 mm to produce a sleeve roll having a wall thickness of 60 mm. . The rotation speed was set so that the centrifugal force on the inner surface of the sleeve roll was 140 G.
第２図に各スリーブの鋳放し表面から内面までのVC炭
化物量の変化の指標となるＶ量の変化を示す。 FIG. 2 shows a change in the amount of V as an index of a change in the amount of VC carbide from the as-cast surface to the inner surface of each sleeve.
本発明材（ａ）では、VC炭化物の内面側へ偏析が少な
いのに対し、従来材（ｂ）では偏析程度が大きく、スリ
ーブ内面側において、Ｖ量が著しく増加していることが
わかる。It can be seen that in the material of the present invention (a), the segregation of the VC carbide is small on the inner surface side, whereas in the conventional material (b), the degree of segregation is large, and the V amount is significantly increased on the inner surface side of the sleeve.
実施例３ 第４表に示す組成の外殻層及び内層を有し、胴径450m
m、胴長750mmの複合ロールを以下に示す手順により製造
した。Example 3 A shell diameter of 450 m having an outer shell layer and an inner layer having the composition shown in Table 4
A composite roll having a length of 750 mm and a length of 750 mm was manufactured by the following procedure.
まず、高周波溶解炉にて外殻層の溶湯を溶解し、1450
℃にて回転する遠心鋳造用鋳型内に450kg鋳込んだ。こ
の時同時に外殻層内面の酸化防止用フラックスを吹き込
んだ。外殻層の鋳込後15分後に、鋳型の回転を停止し、
鋳型を直立させ、ただちに内層となるダクタイル鋳鉄を
1400℃にて鋳込んだ。室温まで冷却後、鋳型を解体し、
粗加工を行い、1000℃から放冷焼き入れし、その後550
℃にて３回の焼戻しを行う熱処理を行った。熱処理後超
音波探傷及びカラーチェックにて、欠陥のない健全なロ
ールであることを確認した。 First, the molten metal in the outer shell layer was melted in a high frequency
450 kg was poured into a centrifugal casting mold rotating at ℃. At this time, a flux for preventing oxidation of the inner surface of the outer shell layer was blown at the same time. 15 minutes after casting of the outer shell layer, stop the rotation of the mold,
The mold is erected and the inner layer of ductile cast iron
Cast at 1400 ° C. After cooling to room temperature, dismantle the mold,
After roughing, quenching and cooling from 1000 ° C, then 550
A heat treatment of performing tempering three times at ℃ was performed. After heat treatment, it was confirmed by ultrasonic flaw detection and color check that the roll was sound and free from defects.
またこのロールの外殻層の金属組織層及び内層の金属
組織を調べるため、顕微鏡写真を撮った。それらをそれ
ぞれ第１図（１）及び（２）に示す。A micrograph was taken to examine the metallographic structure of the outer shell layer and the inner layer of the roll. They are shown in FIGS. 1 (1) and (2), respectively.
次いで、このロールの胴中央部の内層材の軸方向の引
っ張り試験を行った。境界付近では引っ張り強さ47・3k
g/mm2、伸び率0.41％、中心部では引っ張り強さ44.1kg/
mm2、伸び率0.36％を有し、実用上満足な値であった。Next, an axial tensile test of the inner layer material at the center of the body of the roll was performed. Tensile strength 47.3k near the boundary
g / mm 2 , elongation 0.41%, tensile strength at center 44.1kg /
mm 2 and an elongation of 0.36%, which were practically satisfactory.
実施例４ 胴径450mm及び胴長500mmで、内層が鋼であるロールの
製造例を示す。溶湯成分を第５表に示す。Example 4 A production example of a roll having a body diameter of 450 mm and a body length of 500 mm and an inner layer of steel is shown. Table 5 shows the molten metal components.
〔鋳造条件〕 20゜傾斜式の遠心鋳造機上の回転鋳型内に、外殻層用
溶湯を鋳込温度1420℃で290kg注入し、その直後内面の
酸化を防止するためフラックスを吹き込んだ。外殻層が
凝固した直後に鋳型の回転を停止して直立させ、鋳型を
外層とともに吊り上げて、あらかじめ直立させておいた
ロールジャーナル部を鋳込む鋳型の上に乗せ、更にその
上にロールジャーナル部となる鋳型を乗せ、内層材を15
20℃で注入して鋳型内を充満した。下方鋳型の金型は厚
さ150mm以上とし、上方のジャーナル部となる鋳型はジ
ャーナル部形状を砂型で造型し、更に保温材を用い、下
方から上方への指向性凝固を図った。 [Casting conditions] 290 kg of the melt for the outer shell layer was injected at a casting temperature of 1420 ° C. into a rotary mold on a 20 ° inclined centrifugal caster, and immediately thereafter, a flux was blown to prevent oxidation of the inner surface. Immediately after the outer shell layer is solidified, the rotation of the mold is stopped to erect, the mold is lifted together with the outer layer, and the roll journal part that has been erected in advance is placed on the casting mold, and the roll journal part is further placed thereon. And put the inner layer material to 15
The mold was filled at 20 ° C. to fill the inside. The mold of the lower mold had a thickness of 150 mm or more, and the mold to be the upper journal part was formed with a sand mold in the shape of the journal part, and further, a heat insulating material was used to achieve directional solidification from below to above.
このようにして鋳造したロールは、上方のジャーナル
のネック部表面に浅いクラック状の欠陥が発生したが、
通常の加工代で加工除去することができた。このロール
を外径加工して超音波探傷した結果、境界部に実用上問
題があると考えられるような欠陥は発生せず、内層内も
中心部に軽い引け巣と思われる欠陥が発生したが、実用
上問題ない程度であった。The roll cast in this way had a shallow crack-like defect on the neck surface of the upper journal,
Processing could be removed with the usual processing allowance. As a result of processing the outer diameter of this roll and performing ultrasonic inspection, no defect that seems to have a practical problem occurred at the boundary, and a defect that was thought to be a light shrinkage cavity occurred at the center in the inner layer. , Which was practically acceptable.
また、このロールの胴長方向の中央部から、軸方向の
内層の引張試験片を切り出して、引張試験を行った。そ
の結果境界近くの内層は引張強さ49.8kg/mm2,伸び0.43
％，中心部の内層は引張強さ44.6kg/mm2,伸び0.38％で
あり、実用上問題ない値が得られた。Further, a tensile test piece of an inner layer in the axial direction was cut out from a central portion of the roll in the body length direction, and a tensile test was performed. As a result, the inner layer near the boundary had a tensile strength of 49.8 kg / mm 2 and an elongation of 0.43.
%, The inner layer at the center part had a tensile strength of 44.6 kg / mm 2 , and an elongation of 0.38%.
実施例５ 胴径450mm、胴長750mmで、胴部断面が模式的に第６図
に示すような三重構造の複合ロールの製造例を示す。同
図において８は外殻層、９は中間層、10は内層であり、
このロールの各部の溶湯成分を第６表に示す。Example 5 An example of the production of a composite roll having a body diameter of 450 mm and a body length of 750 mm and a triple structure as schematically shown in FIG. 6 with a body section is shown. In the same figure, 8 is an outer shell layer, 9 is an intermediate layer, 10 is an inner layer,
Table 6 shows the molten metal components of each part of this roll.
20゜傾斜式の遠心鋳造機上の鋳型内に外殻層８の溶湯
を鋳込温度1420℃で4200kg注入し、の直後内面の酸化を
防止するためフラックスを吹き込んだ。外殻層が凝固し
た直後に中間層９の溶湯を1480℃で150kg注入して、中
間層９が完全凝固した直後に内層10の溶湯を1400℃で注
入し、鋳型内を完全に満たして鋳造を完了した。 The molten metal of the outer shell layer 8 was poured into a mold on a 20 ° inclined centrifugal casting machine at a casting temperature of 1420 ° C., and 4200 kg of the molten metal was immediately injected with a flux to prevent oxidation of the inner surface. Immediately after the outer layer solidifies, 150 kg of the molten metal of the intermediate layer 9 is injected at 1480 ° C. Immediately after the intermediate layer 9 is completely solidified, the molten metal of the inner layer 10 is injected at 1400 ° C, and the mold is completely filled and cast. Completed.
鋳造冷却後鋳型を解体し、外径加工として超音波探傷
を行った。外殻層８と中間層９との境界及び中間層９と
内層10との境界ともに欠陥は発生せず、健全な複合ロー
ルが得られた。After cooling the casting, the mold was disassembled and subjected to ultrasonic flaw detection as outer diameter processing. No defects occurred at the boundary between the outer shell layer 8 and the intermediate layer 9 and at the boundary between the intermediate layer 9 and the inner layer 10, and a sound composite roll was obtained.
第４図にこの内層10の金属組織の顕微鏡写真を示す。
内層の黒鉛化は良好で、望ましい金属組織が得られた。FIG. 4 shows a micrograph of the metal structure of the inner layer 10.
The graphitization of the inner layer was good, and a desirable metal structure was obtained.
本発明により従来の鋳鉄ロール材の２〜５倍の耐摩耗
性を有する複合ロールを製造することが可能となった。
このことはロールの寿命延長のみならず、ロール交換頻
度の低減、製品形状の改善、圧延スケジュール自由度の
増加等の効果をもたらすものである。According to the present invention, it has become possible to produce a composite roll having a wear resistance two to five times that of a conventional cast iron roll material.
This not only extends the life of the roll, but also brings effects such as a reduction in roll replacement frequency, an improvement in the product shape, and an increase in the rolling schedule flexibility.
一方、高耐摩耗性ロールの製造法として、粉末金属の
成形による方法も開発されているが、このようなロール
の製造工程は、非常に複雑で製造コストも高く、さらに
は軸材との複合化が困難であるため組立式となり、板用
ロールには適用しにくく、また形鋼用ロールに適用した
場合はカリバー数が制限されることになる。本発明の複
合ロールはこれらの問題点を解決するものである。On the other hand, as a method for producing a highly wear-resistant roll, a method based on molding of powdered metal has also been developed.However, the production process of such a roll is extremely complicated, the production cost is high, and furthermore, a composite with a shaft material is required. Since it is difficult to form a roll, it is of an assembling type and is not easily applied to a roll for a plate, and when applied to a roll for a shaped steel, the number of calipers is limited. The composite roll of the present invention solves these problems.
第１図は、実施例３の複合ロールにおいて、（１）は外
殻層、（２）は内層の金属組織を示す顕微鏡写真であ
り、 第２図は本発明のスリーブロール及び従来材質のスリー
ブロールのＶ量変化を示すグラフであり、 第３図は本発明及び従来例の材質の圧延摩耗試験後のサ
ンプル表面の摩耗深さの測定結果を示すグラフであり、 第４図は実施例５の複合ロールの内層の金属組織を示す
顕微鏡写真であり、 第５図はロールの摩耗試験に用いた圧延摩耗試験機の概
略を示す図であり、 第６図は実施例５に係わる複合ロールの胴部の断面図で
ある。 １……圧延機 ２……上ロール ３……下ロール Ｓ……圧延材 ８……外殻層 ９……中間層 10……内層 a,A……本発明のロール材 b,B,C……従来のロール材FIG. 1 is a micrograph showing (1) an outer shell layer and (2) a metallographic structure of an inner layer in the composite roll of Example 3, and FIG. 2 is a sleeve roll of the present invention and a sleeve of a conventional material. FIG. 3 is a graph showing a change in the amount of V of a roll, FIG. 3 is a graph showing a measurement result of a wear depth of a sample surface after a rolling wear test of materials of the present invention and a conventional example, and FIG. FIG. 5 is a micrograph showing the metal structure of the inner layer of the composite roll of FIG. 5. FIG. 5 is a schematic view of a rolling wear tester used for a roll wear test. FIG. It is sectional drawing of a trunk | drum. DESCRIPTION OF SYMBOLS 1 ... Rolling machine 2 ... Upper roll 3 ... Lower roll S ... Rolled material 8 ... Outer shell layer 9 ... Middle layer 10 ... Inner layer a, A ... Roll material b, B, C of this invention ...... Conventional roll material
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭59−23846（ＪＰ，Ａ) 特開 昭54−86422（ＪＰ，Ａ) 特開 昭62−148005（ＪＰ，Ａ) 特開 昭63−199092（ＪＰ，Ａ) 特開 昭63−235092（ＪＰ，Ａ) 特開 平２−85745（ＪＰ，Ａ) 特開 昭57−198243（ＪＰ，Ａ) 特公 昭59−28620（ＪＰ，Ｂ２) (58)調査した分野(Int.Cl.6，ＤＢ名) C22C 37/00 - 38/60 B21B 27/00──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-23846 (JP, A) JP-A-54-86422 (JP, A) JP-A-62-148005 (JP, A) JP-A 63-148 199092 (JP, A) JP-A-63-235092 (JP, A) JP-A-2-85745 (JP, A) JP-A-57-198243 (JP, A) JP-B-59-28620 (JP, B2) (58) Field surveyed (Int. Cl. 6 , DB name) C22C 37/00-38/60 B21B 27/00
Claims (8)
は鋳鋼の内層材とが溶着一体化した耐摩耗複合ロールに
おいて、外殻層の化学成分が重量比でC1〜４％、Si3％
以下、Mn1.5％以下、Ni4％以下、Cr3.01〜8.21％、Mo8
％以下、W20％以下、V4.66〜10％、残部実質的にFe及び
不可避的不純物元素からなるとともに、Ｃ％＋0.4V％の
値が6.0以下であることを特徴とする耐摩耗複合ロー
ル。1. A wear-resistant composite roll in which an outer shell layer cast by a centrifugal casting method and an inner layer material of cast iron or cast steel are welded and integrated, wherein the chemical composition of the outer shell layer is C1-4%, Si3% by weight ratio.
Below, Mn1.5% or less, Ni4% or less, Cr3.01-8.21%, Mo8
% Or less, W20% or less, V4.66 to 10%, balance substantially consisting of Fe and unavoidable impurity elements, and the value of C% + 0.4V% is 6.0 or less, characterized in that it is a wear-resistant composite roll. .
て、前記外殻層は、上記した化学成分に加えてさらに、
Ti、Zr及びNbからなる群から選ばれる１種又は２種以上
の成分を、合計で５重量％以下含むことを特徴とする耐
摩耗複合ロール。2. The wear-resistant composite roll according to claim 1, wherein the outer shell layer further comprises, in addition to the chemical components described above,
A wear-resistant composite roll comprising a total of 5% by weight or less of one or more components selected from the group consisting of Ti, Zr and Nb.
において、前記外殻層がさらにCoを15重量％以下含有す
ることを特徴とする耐摩耗複合ロール。3. The wear-resistant composite roll according to claim 1, wherein the outer shell layer further contains 15% by weight or less of Co.
複合ロールにおいて、前記内層材がダクタイル鋳鉄であ
ることを特徴とする耐摩耗複合ロール。4. The wear-resistant composite roll according to claim 1, wherein the inner layer material is ductile cast iron.
複合ロールにおいて、前記内層材がねずみ鋳鉄であるこ
とを特徴とする耐摩耗複合ロール。5. A wear-resistant composite roll according to claim 1, wherein said inner layer material is gray cast iron.
複合ロールにおいて、前記内層材が黒鉛鋼であることを
特徴とする耐摩耗複合ロール。6. A wear-resistant composite roll according to claim 1, wherein said inner layer material is graphite steel.
複合ロールにおいて、前記内層材が重量比で2.0％以下
のＣを含有する鋳鋼であることを特徴とする耐摩耗複合
ロール。7. The wear-resistant composite roll according to claim 1, wherein the inner layer material is cast steel containing 2.0% by weight or less of C.
複合ロールにおいて、前記内層材がねずみ鋳鉄又はダク
タイル鋳鉄であり、外殻層と内層との間に重量比で2.0
％以下のＣを含有する合金鋼組成の中間層を有すること
を特徴とする耐摩耗複合ロール。8. The wear-resistant composite roll according to claim 1, wherein the inner layer material is gray cast iron or ductile cast iron, and the weight ratio between the outer shell layer and the inner layer is 2.0.
%. An abrasion-resistant composite roll having an intermediate layer of an alloy steel composition containing at most C.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1311419A JP2778765B2 (en) | 1988-12-02 | 1989-11-30 | Wear resistant composite roll |
| EP90122855A EP0430241B1 (en) | 1989-11-30 | 1990-11-29 | Wear-resistant compound roll |
| DE69024762T DE69024762T2 (en) | 1989-11-30 | 1990-11-29 | Wear-resistant compound roller |
| KR1019900019653A KR940007278B1 (en) | 1989-11-30 | 1990-11-30 | Wear-resistant compound roll |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30567988 | 1988-12-02 | ||
| JP63-305679 | 1988-12-02 | ||
| JP1311419A JP2778765B2 (en) | 1988-12-02 | 1989-11-30 | Wear resistant composite roll |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02258949A JPH02258949A (en) | 1990-10-19 |
| JP2778765B2 true JP2778765B2 (en) | 1998-07-23 |
Family
ID=26564404
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1311419A Expired - Lifetime JP2778765B2 (en) | 1988-12-02 | 1989-11-30 | Wear resistant composite roll |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2778765B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103834852A (en) * | 2014-03-19 | 2014-06-04 | 四川大学 | Tin and niobium composite alloying gray pig iron and production process thereof |
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|---|---|---|---|---|
| JPH04191347A (en) * | 1990-11-26 | 1992-07-09 | Hitachi Metals Ltd | Hollow sleeve material for assembled type rolling roll |
| US5355932A (en) * | 1992-03-06 | 1994-10-18 | Hitachi Metals, Ltd. | Method of producing a compound roll |
| JP2778896B2 (en) * | 1992-03-06 | 1998-07-23 | 日立金属株式会社 | Roll for rolling and manufacturing method thereof |
| JP2700591B2 (en) * | 1992-04-27 | 1998-01-21 | 川崎製鉄株式会社 | Centrifugal casting composite roll |
| JP2601746B2 (en) * | 1992-04-30 | 1997-04-16 | 川崎製鉄株式会社 | Centrifugal casting sleeve roll and its manufacturing method |
| JP2618309B2 (en) * | 1992-04-30 | 1997-06-11 | 川崎製鉄株式会社 | Centrifugal casting sleeve roll and its manufacturing method |
| JP2579575B2 (en) * | 1992-05-08 | 1997-02-05 | 川崎製鉄株式会社 | Centrifugal casting roll and manufacturing method thereof |
| JP2594865B2 (en) * | 1992-05-08 | 1997-03-26 | 川崎製鉄株式会社 | Centrifugal casting roll and manufacturing method thereof |
| JP2784114B2 (en) * | 1992-05-12 | 1998-08-06 | 株式会社クボタ | Composite roll |
| JPH0737656B2 (en) * | 1992-06-23 | 1995-04-26 | 株式会社淀川製鋼所 | Abrasion resistant composite roll |
| JP3006984B2 (en) * | 1993-11-05 | 2000-02-07 | 株式会社淀川製鋼所 | Work roll for hot rolling rough rolling stand |
| JP2822139B2 (en) * | 1993-11-05 | 1998-11-11 | 株式会社淀川製鋼所 | Work roll for hot rolling |
| JP4650728B2 (en) * | 2005-11-01 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4650729B2 (en) * | 2005-11-01 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4650731B2 (en) * | 2005-11-01 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4650730B2 (en) * | 2005-11-01 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4650736B2 (en) * | 2005-11-25 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4650734B2 (en) * | 2005-11-25 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4650737B2 (en) * | 2005-11-25 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4650735B2 (en) * | 2005-11-25 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4650738B2 (en) * | 2005-11-25 | 2011-03-16 | 日立金属株式会社 | Composite roll for rolling |
| JP4926764B2 (en) * | 2007-03-07 | 2012-05-09 | 山陽特殊製鋼株式会社 | High wear resistance, high toughness, high speed tool steel and method for producing the same |
| CN103813864B (en) | 2011-09-21 | 2016-04-13 | 日立金属株式会社 | Hot rolling centrifugal casting composite roll and manufacture method thereof |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5486422A (en) * | 1977-12-21 | 1979-07-10 | Kubota Ltd | Cast alloy for composite roll shell |
| JPS6014095B2 (en) * | 1981-05-29 | 1985-04-11 | 株式会社クボタ | Alloy chilled roll material with excellent crack resistance and wear resistance |
| DE3227807A1 (en) * | 1982-07-24 | 1984-01-26 | Robert Bosch Gmbh, 7000 Stuttgart | METHOD FOR PREVENTING DAMAGE TO A TEMPERATURE-DEPENDENT RESISTANCE ARRANGED IN A FLOW CROSS SECTION BY OVERHEATING AND AIR MEASURING DEVICE FOR CARRYING OUT THE METHOD |
| JPS5923846A (en) * | 1982-07-31 | 1984-02-07 | Kubota Ltd | Chilled alloy material for roll with superior cracking and wear resistance |
| JPS62148005A (en) * | 1985-12-23 | 1987-07-02 | Kawasaki Steel Corp | High-chromium roll |
| JPS63199092A (en) * | 1987-02-12 | 1988-08-17 | Kubota Ltd | Welded overlay roll for hot rolling |
| JPS63235092A (en) * | 1987-03-20 | 1988-09-30 | Kubota Ltd | Alloy for plasma powder buildup welding and buildup-welded roll for hot rolling |
| JPH0639823B2 (en) * | 1987-03-27 | 1994-05-25 | 株式会社大林組 | Joint structure between precast concrete slab and beam |
-
1989
- 1989-11-30 JP JP1311419A patent/JP2778765B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103834852A (en) * | 2014-03-19 | 2014-06-04 | 四川大学 | Tin and niobium composite alloying gray pig iron and production process thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02258949A (en) | 1990-10-19 |
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