1鋁軋制工藝的第一部分

1、鋁軋制工藝1. rolling process of aluminum鋁軋制工藝1.1 overview概況1.1.1 current situation of rolling process軋制工藝的當(dāng)前形式 shipment amount of domestic aluminum products expresses, as shown in fig. 1.1.1, a trend of some decrease for these several years by effect of downturn in the economy, however, the past 10 years

2、 shows approximately double increase. among them, can stockshows the biggest share and increase of its production quantity is remarkable. to comply with this growth in demand, each domestic company has promoted enhancement of rollingmills as shown in table 1.1.1. trend of main equipment enhancement

3、in foreign countries is also shown in table 1.1.1, and new installation rush of rolling mills in usa of 1980s is remarkable. 國(guó)內(nèi)鋁產(chǎn)品消費(fèi)的發(fā)貨數(shù)量如圖1.1.1所示，受經(jīng)濟(jì)蕭條形式的影響，這幾年有一些下降的趨勢(shì)，但是在過去的10年里，大約翻了一番。其中，罐料生產(chǎn)數(shù)量的增長(zhǎng)十分顯著，體現(xiàn)了最大的份額。為了滿足市場(chǎng)需求增長(zhǎng)的需要，每個(gè)國(guó)內(nèi)的公司已經(jīng)進(jìn)行了軋機(jī)的擴(kuò)建，如表1.1.1所示。表1.1.1中也顯示了外國(guó)的主要設(shè)備擴(kuò)建的趨勢(shì)，在80年代美國(guó)軋機(jī)的新安裝潮流十分顯著。

4、 fig5.1.1出口其他國(guó)內(nèi)需求鋁箔料罐料年份生產(chǎn) ( x 10,000 噸/年) 圖1.1.1 transition of shipment amount of domestic aluminum products ( search by japan aluminum association)國(guó)內(nèi)鋁產(chǎn)品裝運(yùn)數(shù)量變化情況（日本鋁業(yè)協(xié)會(huì)研究提供） table 1.1.1 recent trend of enhancement of aluminum rolling mill (after 1981)表1.1.1 近年來鋁軋機(jī)增加的趨勢(shì)(在1981年以后)完成公司工廠熱軋機(jī)冷軋機(jī)1981kobe

5、 steel神鋼mooka (日本)新建2240 mm1650 m/min1983furukawa al古河fukui (日本)新建 r 4320 mm新建2750 mm新建 工廠( furukawa denko at present現(xiàn)在的古河denko )f3t 2850 mmreynolds雷諾茲mccook(美國(guó))新建2240 mmconalcohannibal(美國(guó))新建1984kaiser 愷撒trentwood(美國(guó))更新 f.5tw.m.1730 mmfully cont.1986alcan加鋁logan city(美國(guó))新建 新建新建 工廠pechiney匹茲涅（普基）rhen

6、alu(法國(guó))新建1850 mm1800 m/min1987alcoa美鋁warrick(美國(guó))w.m. 2060 mmalcoa美鋁tennessee(美國(guó))新建2030 mmfully cont.1988furukawa al古河fukui(日本)新建1760 mm1800 m/minkobe steel神鋼mooka(日本)更新 f.3-tf.4-t1990sky alfukaya(日本)新建2240 mm1800 m/min1991sumitomo light metal住友輕金屬nagoya名古屋(日本)新建2240 mm2000 m/min1992mitsubishi al三菱鋁f

7、uji(日本)新建1930 mm1000 m/minsumitomo light metal住友輕金屬kaalnagoya名古屋(日本)更新 f.3-tf.4-t1983mooka (日本,美國(guó))新建2200 mm1650 m/minnote) r: rougher, f: finisher, -t: tandem, xxxx mm: mill width, xxxx m/min: max. rolling speed w.m. : width modification 5t注）r:粗軋機(jī)，f：精軋機(jī)，-t：串聯(lián)，xxxx mm：軋機(jī)寬度，xxxx m/min：最高軋制速度w.m.:寬度修改

8、5tfig. 1.1.2 schematic manufacturing process of aluminum flat productsmanufacturing process of aluminum flat products is shown in fig.1.1.2. 鋁平整軋材的加工工藝見圖1.1.2it is significantly different from steel manufacturing process to have scalping process after casting process in order to remove reverse segre

9、gation layer of cast ingot surface, and direct rolling from casting can not be performed, which results in disadvantage in respect of yield and energy saving. as main quality items shown in table 1.1.2 required for aluminum rolled products, especially surface beauty in case of aluminum is important

10、in addition to mechanical property such as yield strength or elongation, dimension tolerance of thickness or shape與鋼加工工藝有很大的不同，鋁加工在鑄造工藝后有銑床工藝，以去除鑄錠表面的偏析層，并且不能在鑄造后直接進(jìn)行軋制，這在產(chǎn)量和節(jié)省能量方面導(dǎo)致了不利的因素。如表1.1.2中顯示的鋁軋制產(chǎn)品要求的主要質(zhì)量項(xiàng)目，包括機(jī)械特性，例如：屈服強(qiáng)度和延伸率，厚度或形狀的尺寸偏差，如果鋁用于重要的用途，表面美化度也尤為重要。原料 熔化鑄造扁錠鋸切均熱銑面鑄錠制造 卷材板材圓片成品沖片表面處

11、理剪切縱切加熱熱軋冷軋 熱處理拉彎矯 table1.1.2 main quality item required for aluminum rolled products and points of control表1.1.2鋁軋制產(chǎn)品要求的主要質(zhì)量項(xiàng)目和控制點(diǎn)主要質(zhì)量項(xiàng)加工工藝 控制點(diǎn)鑄錠制造工藝化學(xué)成分加熱工藝 加熱溫度 加熱時(shí)間 加熱模式機(jī)械特性熱軋工藝熱粗軋和精軋的軋制溫度冷軋工藝?yán)滠埖某潭?熱處理工藝 熱處理溫度時(shí)間加熱模式.熱軋工藝寬度和長(zhǎng)度方向上的厚度分布尺寸偏差冷軋工藝 長(zhǎng)度方向上的厚度分布外形精整工藝寬度長(zhǎng)度的決定厚度和表面檢查, 板材的拉矯鑄錠制造工藝熔煉時(shí)的除氣鑄造溫度鑄

12、造速度冷卻速度過濾均勻和完美的表面質(zhì)量熱軋工藝軋制油的特性軋制表軋制溫度, 輥印輥磨削 冷軋工藝 軋制油的特性軋制表軋輥粗糙度卷曲/開卷的方式輥印精整工藝輥印和摩擦滑痕的預(yù)防和查找表面處理?xiàng)l件涂層條件 1.1.2 base of rolling process軋制工藝的基礎(chǔ) rolling is a process to continuously reduce thickness of material by 2 cylindrical rolls. volume velocity is constant at entry and delivery sides, and material en

13、try speed is slower than delivery speed since material entry thickness is thicker than delivery thickness. on the other hand, roll peripheral speed is constant, accordingly, there is the speed difference between material speed and roll peripheral speed as shown in fig.1.1.3. a point where material s

14、peed matches with roll speed is called neutral point. the speed difference is in the opposite direction at entry side and delivery side of neutral point, and friction force toward neutral point acts on material. accordingly, rolling force contains increased portion due to friction in addition to flo

15、w stress of material, and pressure distribution of increased portion is called friction hill. deformation of material during rolling is not uniform in thickness direction. fig.1.1.4 shows changing condition during rolling of line which was parallel with thickness direction before rolling. at entry z

16、one, the portion near the surface of material thickness direction is significantly deformed and deformation of the center portion proceeds with delay. the zone enclosed by dotted line is a significantly deformed portion. these nonuniform deformation is effected by thickness, roll diameter and materi

17、al property. 軋制工藝就是用2個(gè)圓柱形的軋輥連續(xù)的減少材料的厚度。在出口和入口的質(zhì)量流是保持不變的，由于材料入口厚度比出口厚，所以材料入口的速度比出口慢。另一方面，軋輥圓周線速度保持不變，相應(yīng)地，在材料速度和軋輥圓周速度之間存在速度差，如表1.1.3所示。在材料速度和軋輥圓周速度相同位置的點(diǎn)稱為中性點(diǎn)。速度差在中性點(diǎn)的輸入側(cè)和輸出側(cè)的方向相反，并且有作用在材料上的朝向中性點(diǎn)的摩擦力。因此，除材料的流動(dòng)應(yīng)力以外，軋制力還包括由于摩擦力而增加的部分，增加部分的作用力分配形狀稱為摩擦峰（希爾區(qū)）。在軋制過程中的材料變形在厚度方向上是不均勻的。如圖1.1.4所示，軋制前與厚度方向平行的參考

18、線，在軋制過程中發(fā)生變化。在入口區(qū)域，靠近材料厚度方向表面的部分發(fā)生大的變形，中心部分的變形滯后。圖中虛線圈入的區(qū)域是大變形區(qū)。這些不均勻的變形受厚度、輥徑和材料特性的影響。fig.1.1.5 shows condition of deformation of material top end and side at hot rolling of thicker material. when top end is observed from the top surface, so-called gingko biloba shaped width widening is shown. widt

19、h widening deformation at heavy thickness is often double bulge deformation at material width edge part. for hot rolled material, double bulge deformation grows into lamination. also, when top end is observed from side, so called alligator is shaped. however, when thickness/width ratio is small like

20、 cold rolling, the above nonuniform deformation is limited to the partial portion of material edge and is generally considered the second dimensional deformation of thickness direction and rolling direction.圖1.1.5顯示，較厚材料在熱軋過程中，材料的頂端和側(cè)面的變形條件。當(dāng)從上表面觀察頂端時(shí)，就可以看到所謂的銀杏二裂片形寬展。對(duì)于很厚的材料，寬展變形常常在材料寬度邊緣部分出現(xiàn)雙凸變形（雙

21、鼓形）。對(duì)于熱軋材料，雙凸變形變成層壓。同樣，當(dāng)從側(cè)面觀察頂端時(shí)，就會(huì)看到鱷魚嘴形。但是，當(dāng)厚度寬度比很小時(shí)，例如冷軋，以上不均勻變形就被限制在材料邊緣的部分區(qū)域，并且通?？紤]為厚度方向和軋制方向上的二維尺寸變形。 輥 材料流動(dòng)應(yīng)力圖1.1.3軋輥和材料的速度差和軋制力摩擦峰材料輸出方向材料速度軋輥圓周速度材料入口速度 軋制應(yīng)力速度差出口入口中性點(diǎn) 輥 入口出口圖.1.1.4軋制過程中的變形 圖.1.1.5 頂端和側(cè)面的不均勻變形。鱷魚嘴形 銀杏寬展 變形后之前鱷魚嘴變形 層壓軋制方向 厚度方向厚度方向?qū)挾确较騧aterial deformation during rolling is dec

22、ided by coupling with deformation of roll. when deformed component of roll is considered in case of basic 4 high rolling mill, there are, as shown in fig.1.1.6, flat deformation and deflection of work roll surface, contact flat deformation of both rolls, deflection of back up roll and thermal crown

23、of both rolls. 在軋制過程中，通過結(jié)合輥的變形決定材料變形。當(dāng)在使用基本的4輥軋機(jī)的情況下，考慮輥元件的變形時(shí)，如圖1.1.6所示，這里有，工作輥表面的壓扁和撓性彎曲（偏轉(zhuǎn)）、兩種輥的接觸壓扁、支撐輥撓性彎曲和兩種輥的熱凸度。accordingly, for usual material to be rolled, thickness distributes in the width direction. distributing condition of thickness in the width direction or its degree is called crown

24、. 因此，對(duì)于被軋制的通常材料，厚度分配在寬度方向上。厚度在寬度方向上的分配條件或它的等級(jí)稱為凸度。crown is expressed, as shown in fig.1.1.7, thickness difference (hc-he) between the width center part thickness and the thickness at certain distance x from the width edge. also, the ratio of the thickness difference against the center thickness (hc-

25、he)/ hc x 100 is defined as crown rate. when crown rate is changed at entry side and delivery side, the difference of elongation is caused for delivery material. 如圖1.1.7，凸度表示為，在寬度中心部分厚度，和離寬度邊緣一定距離x處的厚度之間的厚度差(hc-he)。并且把厚度差除以中心厚度的比，(hc-he)/ hc x 100，定義為凸度率。當(dāng)凸度率在入口側(cè)和入口側(cè)發(fā)生變化時(shí)，導(dǎo)致了輸出材料的伸長(zhǎng)率差（板形缺陷）。for exam

26、ple, when material of small entry crown rate changes to big delivery crown rate, lengthwise elongation of the width edge part becomes bigger than that of the width center part, which results in so-called edge wave.例如，當(dāng)較小入口凸度率材料變成較大出口凸度率，邊緣部分的縱向伸長(zhǎng)率，變?yōu)楸戎行牟糠值目v向伸長(zhǎng)率大，這導(dǎo)致了所謂的邊緣波。contact load with back up

27、roll(a) flat deformation and deflection of work roll(b) deflection of back up roll(c) contact flat deformation of both rolls(d) thermal crown of both rollsfig.1.1.6 deformed component of rollscrowncrown ratefig.1.1.7 definition of crown軋制負(fù)荷與工作輥的接觸負(fù)荷與支撐輥的接觸負(fù)荷（a）工作輥的壓扁和偏轉(zhuǎn)（b）支撐輥的偏轉(zhuǎn)（c）每個(gè)輥的接觸壓扁變形（d）每個(gè)輥的熱

28、凸度圖1.1.6 輥元件的變形凸度凸度率圖1.1.7 凸度的定義various shapes occur according to change of crown rate as shown in table 1.1.3. 根據(jù)凸度率的變化而發(fā)生的各種板形缺陷，如表1.1.3所示：table 1.1.3 category of shape表1.1.3 板形缺陷的分類描述外形 外形的解釋邊緣波寬度wave occurs at width edge part and center part is flat.波紋發(fā)生在寬度邊緣部分，中心部分是平整的。中心波紋wear occurs at width

29、center part and edge part is flat波紋發(fā)生在寬度中心部分，邊緣部分是平整的。區(qū)域波（1/4波）ware occurs between width edge part and width center part.波紋發(fā)生在寬度邊緣部分和寬度中間部分之間。單邊波wave occurs at only single side edge of width.波紋近發(fā)生在寬度的單側(cè)邊緣部分。平直/整 whole parts are flat.全部是平整的shape of material is expressed by elongation difference rate

30、() or steepness() as shown in fig.1.1.8. ratio of shape change due to change of crown rate is called shape change coefficient(), which is defined as follows :材料的板形用伸展率差()或陡度()來表示，如圖1.1.8所示。由于凸度率的變化而導(dǎo)致的板形變化比，稱為板形變化系數(shù)()，其定義如下： = (-0)/(cr-cr0) where, cr = delivery crown rate, cr0= entry crown rate = de

31、livery elongation difference rate, 0 = entry elongation difference rate.式中，cr = 出口凸度率 cr0= 入口凸度率 = 出口伸展率差, 0 = 入口伸展率差 如圖1.1.9所示，板形變化系數(shù)取決于合金組成、厚度(h)、寬度(b)和軋輥直徑(d)，并且板形變化系數(shù)隨著h/b的減少而增加，隨h/b的增加而減少。從而，在h/b較小的冷軋時(shí)，如果嘗試改變凸度，板形的變化就會(huì)很大，不能順利進(jìn)行軋制。關(guān)于這一點(diǎn)，有必要在h/b較大的熱軋時(shí)控制凸度。 圖 1.1.8板形的表達(dá)方法 fig. 5.1.8 expression met

32、hod of shape 伸展偏差率邊緣部分的長(zhǎng)度中心部分的長(zhǎng)度陡度波紋的高度波距寬度view 截面 aa伸展偏差率和陡度之間的關(guān)系 fig1.1.9 shape changing coefficient fig. 5.1. shape changing coefficient形變系數(shù)()1.1.3 theory of rolling軋制原理 as the most fundamental theory for rolling, there is karmans theory. this theory premisesuniform deformation, is extremely elem

33、entary and understandable, however, there could occur such contradiction to recognize that friction stress becomes bigger than shearing yield stress of material due to assumption of coulomb friction in whole contact zone between roll and material. 最基本的軋制原理是卡門原理。卡門原理以均勻變形為前提，是非?；竞腿菀桌斫獾?，但是，這可能發(fā)生一些誤解，

34、依據(jù)在輥和材料之間整個(gè)接觸區(qū)域都存在庫侖摩擦的假設(shè)，使摩擦應(yīng)力變得比材料的剪切屈服應(yīng)力大。accordingly this theory is used for cold rolling where friction tress is small. in karmans method premising uniform deformation, horizontal pressure and vertical pressure are uniform in thickness direction, and these are presumed as main stresses. conside

35、ring horizontal component of force of material of the hatched part in fig.1.1.10, the following basic equation called karmans differential equation is obtained. 從而，此原理用于摩擦應(yīng)力較小的冷軋?？ㄩT方法的前提是，均勻變形，在厚度方向上的水平壓力和垂直壓力均勻，并且這些都假定為主應(yīng)力?？紤]到圖1.1.10中陰影部分材料受力的水平分力，可以得到以下基本方式，被稱為卡門微分方程。 fig.1.1.10 geometrical relati

36、on of rolling and acting stress圖1.1.10，軋制力和軋制力水平分量的幾何關(guān)系 fig. 5.1.10 geometrical relation of rolling and acting stress 式中, : 中性點(diǎn)的入口側(cè) : 中性點(diǎn)的出口側(cè) h : 厚度 : 水平方向壓力 p : 厚度方向的垂直壓力 :接觸弧上法線和垂線之間的夾角。 : 摩擦系數(shù) : 軋制方向的定位(水平方向) solution of the above equation is obtained by nadai or hill or others under various pres

37、umption, but the solution used most generally for aluminum cold rolling is approximate solution of bland & ford. rolling load is generally expressed by the following equation.以上方程的解由nadai或希爾或其它人在不同的假定下得到。但在鋁冷軋制過程中使用最普遍的卻是布蘭德&福特的近似解法。軋制負(fù)載一般表達(dá)為以下方程： p = kbqp .（2）式中p : 軋制負(fù)載, k : 材料的流動(dòng)應(yīng)力, b : 材料寬度 r : 壓

38、扁輥半徑, h : 減少量 qp : 軋制力函數(shù) in approximate solution of bland & ford, rolling force function qp is the equation including integration and, in most cases, used by application of the approximate expression. for example, the approximate expression by hill is shown by the following equation. 在布蘭德&福特的近似解法中，軋

39、制力函數(shù)qp是包含積分的方程，在大多數(shù)情況下，使用近似公式。例如，希爾的近似式表示為以下方程。 r : 壓下率 whereas karmans theory premises uniform deformation, orowan proposed so-called nonuniform deformation theory by not presuming uniform deformation in thickness direction but considering shearing stress. orowans theory developed more general theo

40、ry without presuming coulomb friction. balance of horizontal direction force is given as per orowans theory by the following equation : 由于卡門的原理以均勻變形為前提，orowan不假設(shè)在厚度方向上均勻變形，而考慮剪應(yīng)力，提出了所謂的不均勻變形原理。orowan的原理發(fā)展了更多的不考慮庫侖摩擦的一般原理。根據(jù)orowan的原理，給出了以下水平方向力的平衡方程： where, q is force of horizontal direction and the

41、following equation is obtained by x = rsin, d = rcosd式中，q是水平方向的力，并通過以下方程得到x = rsin, d = rcosd equation(6) is orowans differential equation. sims found the pressure distribution from equation(6) assuming sticking friction condition in the whole contact arc and induced the following rolling load equat

42、ion :方程（6）是orowan的微分方程。西姆斯假設(shè)在整個(gè)接觸弧上的粘著摩擦條件，從方程（6）中找到了壓力分布，并引入了以下軋制負(fù)載方程： 式中hn : 中性點(diǎn)的厚度 : 中性角 h0 : 入口厚度 h1 : 出口厚度 also, shida obtained the following approximation of rolling force function in sims formula. 并且，在希姆斯的公式中，shida得到了以下軋制力函數(shù)的近似值： when hot rolling of aluminum is targeted, the above shidas appr

43、oximate expression is often used. however, rolling oil has been used from old times for aluminum hot rolling, and contact surface between roll and material is not perfect sticking friction condition but mixed friction condition. in this connection, there is also application of regression formula to

44、rolling force function is also performed by means of multiple regression by factors such as , , r through direct solving orowans differential equation which can handle mixed friction condition, by numerical calculation. it is necessary to consider effect of tension for analyzing hot finish rolling o

45、r cold rolling.當(dāng)以鋁熱軋為目標(biāo)時(shí)，經(jīng)常使用以上shida的近似值表達(dá)方法。但是，在鋁熱軋過程中，由于軋制油使用了很多次，并且輥與材料的之間的接觸表面不再有完美的粘著摩擦條件，而是混合摩擦條件。關(guān)于這一點(diǎn)，通過能處理混合摩擦條件的orowan的微分方程，通過, , r，等因數(shù)的多次回歸，通過數(shù)值計(jì)算，應(yīng)用回歸公式計(jì)算軋制力函數(shù)。對(duì)于分析熱精軋或冷軋時(shí)，有必要考慮張力的影響。the method to consider effect of tension on the above theory is, according to bland & sims, to use equiva

46、lent flow stress(keq) by tension obtained by substituting material flow stress to k-(h0/h)0 at the entry side from neutral point and k-(h1/h)1 at the delivery side from neutral point. 根據(jù)布蘭德&希姆斯的原理，考慮以上原理的張力效應(yīng)的方法是，使用張力的等效流動(dòng)應(yīng)力(keq)，通過替換材料流動(dòng)應(yīng)力，中性點(diǎn)入口側(cè)為k-(h0/h)0和中性點(diǎn)出口側(cè)為k-(h1/h)1得到張力。 0 : 入口張力, 1 : 出口張力th

47、e above theory is second dimensional deformation theory which considers only deformation in thickness direction and rolling direction. as method to handle deformation in width direction, there are upper bound method and finite element method. fig.1.1.11 is an example that metal flow at center surfac

48、e of thickness direction in roll bite was calculated using the finite element method. phenomenon of material flow to the width direction is analyzed and utilized for study of thickness distribution in the width direction.以上原理是二維變形原理，僅考慮厚度方向和軋制方向上的變形。作為處理厚度方向上變形的方法，有上限法和有限元法。圖1.1.11是使用有限元法，計(jì)算輥咬入軋件厚度方

49、向的中心表面的金屬流的一個(gè)示例。分析和利用寬度方向上材料流的現(xiàn)象，用于研究寬度方向上的厚度分配。 到咬入口表面的距離mm 低碳鋼(c:0.05%) 高抗拉強(qiáng)度鋼 (c:0.18%, mn:1.2%) 工業(yè)純度鋁 鋁鎂合金靜態(tài)流動(dòng)應(yīng)力(n/mm2)總壓縮率到寬度中心的距離 mm 圖1.1.11 金屬流的計(jì)算示例 圖1.1.12 冷軋的流動(dòng)應(yīng)力 1.1.4 flow stress and friction coefficient流動(dòng)應(yīng)力和摩擦系數(shù)flow stress of aluminum and aluminum alloy is one of the most important facto

50、rs in prediction of rolling load and various measurements or mathematization have been performed. since, in case of aluminum, chemical composition differs depending on material kind, mathematization can not be performed like carbon steel which is mathematized by carbon amonut as parameter, and setti

51、ng of parameter of equation based on the measured data for each kind of material has been performed. recently, accurate hot flow stress equation is proposed which incorporates content of various alloy elements. 在已經(jīng)執(zhí)行的軋制負(fù)載和各種測(cè)量或數(shù)學(xué)處理的推算中，鋁和鋁合金的流動(dòng)應(yīng)力是最重要的因素。在鋁加工中，由于化學(xué)成分因材料類型的不同而不同，不能像碳鋼那樣，以含碳量作為參數(shù)進(jìn)行數(shù)學(xué)處理

52、，方程的參數(shù)設(shè)置是基于已執(zhí)行了每種材料類型的測(cè)量數(shù)據(jù)的基礎(chǔ)上。近年來，提出了包含各種合金元素的，精確熱流體應(yīng)力方程。kinds of aluminum and aluminum alloy are more as compared with steel material. value ofcold flow stress for steel material is, as shown in fig. 1.1.12, in the range of approximate200 n/mm2 to 1000 n/mm2 even though including from low carbon steel of low flow stressto high tensile strength steel of high flow stress. on the other hand, in case of aluminum, it has significantly wide range(approximate 13 times) from 30 n/mm2 to 400 n/mm2 from industrial pure aluminum to al-mg alloy. hot flow stress equation, which has been u