1铝轧制工艺的第一部分

1、铝轧制工艺1. rolling process of aluminum铝轧制工艺1.1 overview概况1.1.1 current situation of rolling process轧制工艺的当前形式 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. 国内铝产品消费的发货数量如图1.1.1所示，受经济萧条形式的影响，这几年有一些下降的趋势，但是在过去的10年里，大约翻了一番。其中，罐料生产数量的增长十分显著，体现了最大的份额。为了满足市场需求增长的需要，每个国内的公司已经进行了轧机的扩建，如表1.1.1所示。表1.1.1中也显示了外国的主要设备扩建的趋势，在80年代美国轧机的新安装潮流十分显著。

4、 fig5.1.1出口其他国内需求铝箔料罐料年份生产 ( x 10,000 吨/年) 图1.1.1 transition of shipment amount of domestic aluminum products ( search by japan aluminum association)国内铝产品装运数量变化情况（日本铝业协会研究提供） table 1.1.1 recent trend of enhancement of aluminum rolling mill (after 1981)表1.1.1 近年来铝轧机增加的趋势(在1981年以后)完成公司工厂热轧机冷轧机1981kobe

5、 steel神钢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 工厂( furukawa denko at present现在的古河denko )f3t 2850 mmreynolds雷诺兹mccook(美国)新建2240 mmconalcohannibal(美国)新建1984kaiser 恺撒trentwood(美国)更新 f.5tw.m.1730 mmfully cont.1986alcan加铝logan city(美国)新建 新建新建 工厂pechiney匹兹涅（普基）rhen

6、alu(法国)新建1850 mm1800 m/min1987alcoa美铝warrick(美国)w.m. 2060 mmalcoa美铝tennessee(美国)新建2030 mmfully cont.1988furukawa al古河fukui(日本)新建1760 mm1800 m/minkobe steel神钢mooka(日本)更新 f.3-tf.4-t1990sky alfukaya(日本)新建2240 mm1800 m/min1991sumitomo light metal住友轻金属nagoya名古屋(日本)新建2240 mm2000 m/min1992mitsubishi al三菱铝f

7、uji(日本)新建1930 mm1000 m/minsumitomo light metal住友轻金属kaalnagoya名古屋(日本)更新 f.3-tf.4-t1983mooka (日本,美国)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:粗轧机，f：精轧机，-t：串联，xxxx mm：轧机宽度，xxxx m/min：最高轧制速度w.m.:宽度修改

8、5tfig. 1.1.2 schematic manufacturing process of aluminum flat productsmanufacturing process of aluminum flat products is shown in fig.1.1.2. 铝平整轧材的加工工艺见图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与钢加工工艺有很大的不同，铝加工在铸造工艺后有铣床工艺，以去除铸锭表面的偏析层，并且不能在铸造后直接进行轧制，这在产量和节省能量方面导致了不利的因素。如表1.1.2中显示的铝轧制产品要求的主要质量项目，包括机械特性，例如：屈服强度和延伸率，厚度或形状的尺寸偏差，如果铝用于重要的用途，表面美化度也尤为重要。原料 熔化铸造扁锭锯切均热铣面铸锭制造 卷材板材圆片成品冲片表面处

11、理剪切纵切加热热轧冷轧 热处理拉弯矫 table1.1.2 main quality item required for aluminum rolled products and points of control表1.1.2铝轧制产品要求的主要质量项目和控制点主要质量项加工工艺 控制点铸锭制造工艺化学成分加热工艺 加热温度 加热时间 加热模式机械特性热轧工艺热粗轧和精轧的轧制温度冷轧工艺冷轧的程度 热处理工艺 热处理温度时间加热模式.热轧工艺宽度和长度方向上的厚度分布尺寸偏差冷轧工艺 长度方向上的厚度分布外形精整工艺宽度长度的决定厚度和表面检查, 板材的拉矫铸锭制造工艺熔炼时的除气铸造温度铸

12、造速度冷却速度过滤均匀和完美的表面质量热轧工艺轧制油的特性轧制表轧制温度, 辊印辊磨削 冷轧工艺 轧制油的特性轧制表轧辊粗糙度卷曲/开卷的方式辊印精整工艺辊印和摩擦滑痕的预防和查找表面处理条件涂层条件 1.1.2 base of rolling process轧制工艺的基础 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. 轧制工艺就是用2个圆柱形的轧辊连续的减少材料的厚度。在出口和入口的质量流是保持不变的，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，轧辊圆周线速度保持不变，相应地，在材料速度和轧辊圆周速度之间存在速度差，如表1.1.3所示。在材料速度和轧辊圆周速度相同位置的点称为中性点。速度差在中性点的输入侧和输出侧的方向相反，并且有作用在材料上的朝向中性点的摩擦力。因此，除材料的流动应力以外，轧制力还包括由于摩擦力而增加的部分，增加部分的作用力分配形状称为摩擦峰（希尔区）。在轧制过程中的材料变形在厚度方向上是不均匀的。如图1.1.4所示，轧制前与厚度方向平行的参考

18、线，在轧制过程中发生变化。在入口区域，靠近材料厚度方向表面的部分发生大的变形，中心部分的变形滞后。图中虚线圈入的区域是大变形区。这些不均匀的变形受厚度、辊径和材料特性的影响。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.图1.1.5显示，较厚材料在热轧过程中，材料的顶端和侧面的变形条件。当从上表面观察顶端时，就可以看到所谓的银杏二裂片形宽展。对于很厚的材料，宽展变形常常在材料宽度边缘部分出现双凸变形（双

21、鼓形）。对于热轧材料，双凸变形变成层压。同样，当从侧面观察顶端时，就会看到鳄鱼嘴形。但是，当厚度宽度比很小时，例如冷轧，以上不均匀变形就被限制在材料边缘的部分区域，并且通常考虑为厚度方向和轧制方向上的二维尺寸变形。 辊 材料流动应力图1.1.3轧辊和材料的速度差和轧制力摩擦峰材料输出方向材料速度轧辊圆周速度材料入口速度 轧制应力速度差出口入口中性点 辊 入口出口图.1.1.4轧制过程中的变形 图.1.1.5 顶端和侧面的不均匀变形。鳄鱼嘴形 银杏宽展 变形后之前鳄鱼嘴变形 层压轧制方向 厚度方向厚度方向宽度方向material 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. 在轧制过程中，通过结合辊的变形决定材料变形。当在使用基本的4辊轧机的情况下，考虑辊元件的变形时，如图1.1.6所示，这里有，工作辊表面的压扁和挠性弯曲（偏转）、两种辊的接触压扁、支撑辊挠性弯曲和两种辊的热凸度。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，对于被轧制的通常材料，厚度分配在宽度方向上。厚度在宽度方向上的分配条件或它的等级称为凸度。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. 如图1.1.7，凸度表示为，在宽度中心部分厚度，和离宽度边缘一定距离x处的厚度之间的厚度差(hc-he)。并且把厚度差除以中心厚度的比，(hc-he)/ hc x 100，定义为凸度率。当凸度率在入口侧和入口侧发生变化时，导致了输出材料的伸长率差（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，当较小入口凸度率材料变成较大出口凸度率，边缘部分的纵向伸长率，变为比中心部分的纵向伸长率大，这导致了所谓的边缘波。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轧制负荷与工作辊的接触负荷与支撑辊的接触负荷（a）工作辊的压扁和偏转（b）支撑辊的偏转（c）每个辊的接触压扁变形（d）每个辊的热

28、凸度图1.1.6 辊元件的变形凸度凸度率图1.1.7 凸度的定义various shapes occur according to change of crown rate as shown in table 1.1.3. 根据凸度率的变化而发生的各种板形缺陷，如表1.1.3所示：table 1.1.3 category of shape表1.1.3 板形缺陷的分类描述外形 外形的解释边缘波宽度wave occurs at width edge part and center part is flat.波纹发生在宽度边缘部分，中心部分是平整的。中心波纹wear occurs at width

29、center part and edge part is flat波纹发生在宽度中心部分，边缘部分是平整的。区域波（1/4波）ware occurs between width edge part and width center part.波纹发生在宽度边缘部分和宽度中间部分之间。单边波wave occurs at only single side edge of width.波纹近发生在宽度的单侧边缘部分。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()来表示，如图1.1.8所示。由于凸度率的变化而导致的板形变化比，称为板形变化系数()，其定义如下： = (-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 如图1.1.9所示，板形变化系数取决于合金组成、厚度(h)、宽度(b)和轧辊直径(d)，并且板形变化系数随着h/b的减少而增加，随h/b的增加而减少。从而，在h/b较小的冷轧时，如果尝试改变凸度，板形的变化就会很大，不能顺利进行轧制。关于这一点，有必要在h/b较大的热轧时控制凸度。 图 1.1.8板形的表达方法 fig. 5.1.8 expression met

32、hod of shape 伸展偏差率边缘部分的长度中心部分的长度陡度波纹的高度波距宽度view 截面 aa伸展偏差率和陡度之间的关系 fig1.1.9 shape changing coefficient fig. 5.1. shape changing coefficient形变系数()1.1.3 theory of rolling轧制原理 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. 最基本的轧制原理是卡门原理。卡门原理以均匀变形为前提，是非常基本和容易理解的，但是，这可能发生一些误解，

34、依据在辊和材料之间整个接触区域都存在库仑摩擦的假设，使摩擦应力变得比材料的剪切屈服应力大。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. 从而，此原理用于摩擦应力较小的冷轧。卡门方法的前提是，均匀变形，在厚度方向上的水平压力和垂直压力均匀，并且这些都假定为主应力。考虑到图1.1.10中阴影部分材料受力的水平分力，可以得到以下基本方式，被称为卡门微分方程。 fig.1.1.10 geometrical relati

36、on of rolling and acting stress图1.1.10，轧制力和轧制力水平分量的几何关系 fig. 5.1.10 geometrical relation of rolling and acting stress 式中, : 中性点的入口侧 : 中性点的出口侧 h : 厚度 : 水平方向压力 p : 厚度方向的垂直压力 :接触弧上法线和垂线之间的夹角。 : 摩擦系数 : 轧制方向的定位(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或希尔或其它人在不同的假定下得到。但在铝冷轧制过程中使用最普遍的却是布兰德&福特的近似解法。轧制负载一般表达为以下方程： p = kbqp .（2）式中p : 轧制负载, k : 材料的流动应力, b : 材料宽度 r : 压

38、扁辊半径, h : 减少量 qp : 轧制力函数 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. 在布兰德&福特的近似解法中，轧

39、制力函数qp是包含积分的方程，在大多数情况下，使用近似公式。例如，希尔的近似式表示为以下方程。 r : 压下率 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 : 由于卡门的原理以均匀变形为前提，orowan不假设在厚度方向上均匀变形，而考虑剪应力，提出了所谓的不均匀变形原理。orowan的原理发展了更多的不考虑库仑摩擦的一般原理。根据orowan的原理，给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，并通过以下方程得到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。西姆斯假设在整个接触弧上的粘着摩擦条件，从方程（6）中找到了压力分布，并引入了以下轧制负载方程： 式中hn : 中性点的厚度 : 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得到了以下轧制力函数的近似值： 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.当以铝热轧为目标时，经常使用以上shida的近似值表达方法。但是，在铝热轧过程中，由于轧制油使用了很多次，并且辊与材料的之间的接触表面不再有完美的粘着摩擦条件，而是混合摩擦条件。关于这一点，通过能处理混合摩擦条件的orowan的微分方程，通过, , r，等因数的多次回归，通过数值计算，应用回归公式计算轧制力函数。对于分析热精轧或冷轧时，有必要考虑张力的影响。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. 根据布兰德&希姆斯的原理，考虑以上原理的张力效应的方法是，使用张力的等效流动应力(keq)，通过替换材料流动应力，中性点入口侧为k-(h0/h)0和中性点出口侧为k-(h1/h)1得到张力。 0 : 入口张力, 1 : 出口张力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.以上原理是二维变形原理，仅考虑厚度方向和轧制方向上的变形。作为处理厚度方向上变形的方法，有上限法和有限元法。图1.1.11是使用有限元法，计算辊咬入轧件厚度方

49、向的中心表面的金属流的一个示例。分析和利用宽度方向上材料流的现象，用于研究宽度方向上的厚度分配。 到咬入口表面的距离mm 低碳钢(c:0.05%) 高抗拉强度钢 (c:0.18%, mn:1.2%) 工业纯度铝 铝镁合金静态流动应力(n/mm2)总压缩率到宽度中心的距离 mm 图1.1.11 金属流的计算示例 图1.1.12 冷轧的流动应力 1.1.4 flow stress and friction coefficient流动应力和摩擦系数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. 在已经执行的轧制负载和各种测量或数学处理的推算中，铝和铝合金的流动应力是最重要的因素。在铝加工中，由于化学成分因材料类型的不同而不同，不能像碳钢那样，以含碳量作为参数进行数学处理

52、，方程的参数设置是基于已执行了每种材料类型的测量数据的基础上。近年来，提出了包含各种合金元素的，精确热流体应力方程。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