冷变成型过程的有限元数值模拟

【作者】 王飞龙；

【导师】 张代明；

【作者基本信息】 昆明理工大学 ， 材料学， 2004， 硕士

【摘要】 本文首先对国内外冷弯成型领域及其数值模拟领域的工作进展情况进行了概括和总结，阐述了本文立题的背景和意义。接着，在第二章，本文从一个冷弯成型数值模拟工作者的角度出发，对在冷弯成型过程的数值模拟工作中所涉及到的非常抽象的有限元理论进行了具体化的移植和必要的论证，使其顺利地成为了冷弯成型过程有限元数值模拟的理论基础。在第三章，本文利用大型结构分析软件ANSYS-LS／DYNA对冷弯成型过程进行了模拟和详细的分析，从建立冷弯成型过程的有限元计算模型出发，依次模拟和分析了冷弯成型的咬入过程、稳态成型过程、弹复过程及其全过程，总结出了一些对实际生产具有参考意义的信息。在第四章，本文对冷弯成型过程中普遍存在且非常重要的回弹现象进行了详细的分析和模拟，考虑了单元大小、材料的硬化模型以及动态效应等因素对回弹量模拟值的精确度的影响，真正地使模拟结果能够用于指导实际生产。在第五章，本文对一些模拟结果和实验结果进行了对比和分析，证实了本文中的理论和技术基本上是能够满足实际应用并指导实践的。在文章的最后部分，本文对笔者的主要工作进行了回顾和总结，并提出了一些值得进一步研究的问题。 总的说来，本文的研究成果可概括如下： 1)利用大型结构分析软件ANSYS／LS-DYNA对冷弯成型过程进行了数值模拟，并对模拟结果进行了分析，获得了对实际生产有一定指导意义的理论和技术； 2)研究表明，冷弯成型回弹规律的解析模型是不可能建立出来的，即不可能得到通用的精确的回弹计算公式，只能找到其主要影响因素，然后通过计算机数值模拟进行具体问题具体分析； 3)模拟结果表明，单元越小，模拟出的回弹量越接近真实值；使用随动硬化模型模拟的结果要比使用等向强化模型的更接近于实验结果；计算时间越短，动态效应对回弹的影响越大。更多还原

【Abstract】 The paper firstly summarizes some things about cold-roll forming and its simulation in our country and international, introduces the work’s background and significance. Secondly, beginning as a worker to research simulation of cold-roll forming, in the chapter 2, the paper makes those much abstract Finite Element Method(FEM) theories which are concerned in the numerical simulations of cold-roll forming into concrete planting and necessory proving, then makes them become the theory base of cold-roll forming’s FEM simulation. In the chapter 3, the paper simulates and analyzes cold-roll forming progress using ANSYS/LS-DYNA, a large structual analasis program, from constructing cold-roll forming progress’ FEM model, to simulating and analyzing cold-roll forming’s inducting progress, stable progress, springback progress , and all those progress, then generalizes some valuable informations to real rolling. In the chapter 4, the paper analyzes and simulates springback, the important phenomenon which often exists in the cold-roll forming, has considered some factors which affects springback’s simulating precision, such as the element’s inch, the meterial hardening model, and moving effects, then uses really the simulating products into directing real manufacturing. In the chapter 5, the paper contrasts and analyzes some simulating results and experimental results, proves that the theory and technology in the paper is able to using in real manufacturing and directing practice in general. Finaly, the paper reviews and concludes the auther’s main work and refers some questions which are worthing to researching continuely.In general, the paper’s researching results can be generalized to the following:1) Using the large structual analasis program, ANSYS/LS-DYNA, to simulate cold-roll forming progress, analyze the simulating results, and gain the theory and technology which are useful to directing real manufacturing;2) The springback’s formula of cold-roll forming isn’t found, that’s to say, you can’t gain a general and precise springback formula. You can only find some main factors which affects it, then analyze one thing once using computer simulating;3) The simulating results tell us: The smaller the element is, the closer the simulating springback is to the reality; Springback’s simulating results by using Bilinear Kinemat Model is closer to the reality than by using Bilinear Isotrop Model; The shorter the simulating time, the bigger the moving effects to springback is.更多还原