【作者】 董安平；

【导师】 关小军；

【作者基本信息】 山东大学 ， 材料加工工程， 2005， 硕士

【摘要】 “以有限的坯料资源开发无限多的产品”已经成为众多钢铁企业的工作理念。在利用济钢现有设备进行宽规格翼板钢的开发过程中,面临诸多困难:产品规格多、孔型形状复杂、轧件在孔型中变形和流动规律难以解析描述。为此,定量研究孔型和工艺参数对翼板钢宽展的影响十分重要。 本文利用商业有限元软件ANSYS/LS-DYNA,采用显式动力弹塑性有限元法,模拟翼板钢粗轧前三道次轧制过程。经有限元模型建立、材料选择、单元选择及网格划分、初始边界条件确定、模拟计算等步骤,得到了各道次孔型和工艺的部分参数对轧件宽展及其相应的应力、应变分布的影响规律,分析了孔型腰部的强迫宽展作用,为弯腰大斜度箱形孔轧制翼板钢的显式动力学有限元模拟提供了实例。同时,基于模拟研究结果,对现有孔型和工艺参数进行了优化,优化效果完全可以满足生产宽度大于220mm翼板钢的需要。本文取得的研究成果和相关结论如下: (1)成功地实现了方坯进入弯腰大斜度箱形孔型、拟矩形弯腰大斜度坯进入弯腰大斜度箱形孔型、拟矩形弯腰大斜度坯进入弯腰小斜度箱形孔型的三种轧制过程模拟。模拟结果与现场试验结果吻合较好,表明显式动力学有限元法可有效地进行弯腰大斜度箱形孔型不同坯料轧制过程的仿真和孔型参数优化研究。 (2)揭示了孔型腰部倾角对轧件宽展的影响规律,即轧件宽展随着腰部倾角增大而增加。 (3)分别研究了K10、K9孔型腰部楔高和楔宽对轧件宽展的影响。轧件宽展均随楔高和楔宽增大而增加。 (4)研究了摩擦系数改变对轧件宽展的影响。当摩擦系数在一定范围内变化时,轧件宽展发生相应变化,但变化范围不大。 (5)揭示了腰部圆弧半径对轧件宽展的影响规律,即轧件宽展随圆弧半径增大而减小,但总体变化范围不大。 (6)孔型参数和摩擦系数对轧件宽展的影响程度不同,在本文模拟条更多还原

【Abstract】 "Develop infinity products with limited billets" has been applied to many iron and steel works. There are many difficulties during the process of producing broad wing plate steel, such as different standards of products, complication of pass shape and hard description of the law about deformation in the box passes and metal flows. So it is very important to study the parameters of the pass and techniques for the spread of the wing plate steel.With the aid of commercial finite element analysis code ANSYS/LS-DYNA, this paper simulated the former three rolling process of wing plate steel in a box pass. Every simulation in this paper is 3-D DEM (Dynamic Explicit Method) coupled elastic-plastic analysis. After establishing the FEM model, the selection of material, the determination of element types and the meshing, deciding the initial and boundary conditions, the simulation etc, the variety laws of rolled billet spread and the distribution of strain and stress field affected by some pass and technique parameters were received, and the forced-spread function of the waist was discussed. This paper provides examples for the simulation of the special shaped steel rolling process by DEM. At the same time, the current pass and technique parameters were optimized, the optimized results indicate that it satisfies the manufacture of the exceed 220mm wing plate steel. The paper has some conclusions as follows:(1) Three rolling processes were simulated, the first one is the process of rolling the square billet in a box pass whose waist is bowing and large pitch, the second is the process of rolling the billet whose waist is bowing and large pitch in a alike pass, and the third is the process of rolling the billet whose waist is bowing and large pitch in a box pass whose waist is bowing and smallpitch. The difficulty of the billet biting in SEM (Static Implicit Method) was solved, the simulating results are almost in good agreement with the practice ones. It indicates that explicit dynamics finite element method can be effectively applied in the simulation of the billet rolling process with different shapes and the research on the optimization of the pass.(2) The waist obliquity of the K10 pass, i.e. the spread increases with the increase of the obliquity was discovered.(3) The variety law of rolled billet spread affected by the waist height and waist width of the K10 and K9 pass, i.e. the spread increases with the increase of the waist width and waist height was discovered. The relation between the spread and the waist width and waist height was regressed and the regressed equation was received. The deformation of work piece and stress field together with strain field of cross section of the work piece in rolling area were analyzed.(4) The variety laws of rolled billet spread affected by the friction coefficient were studied. When the friction coefficient varied, the billet spread changed accordingly, but it changed slightly.(5) The variety law of rolled billet spread affected by the arc radius of the K8 pass was studied. When the arc radius varied, the billet spread changed accordingly, and it changed slightly.(6) The effects of the waist obliquity, the waist width, the waist height and some other factors on the rolled billet are different, in the condition of the simulation in this paper, the waist width of the pass is the most principal influential factor, next is waist width and the waist obliquity of the pass, the friction influence is slight. The parameters of the pass and techniques for manufacturing exceed 220mm wing plate steel were decided.(7) The industry examination of the first pass cogging of rolling was carried out in the same conditions with the simulation, and the waist obliquity is 45° and 55° in each examination. The industry examinations of the second and the third pass cogging of rolling were carried out too. The numerical simulation results are almost in goodagreements with the industry examinations.更多还原