异形铝型材挤压成形数值模拟与模具CAD系统开发

发布时间：2018-03-10 01:40

本文选题：铝型材　切入点：挤压模具　出处：《武汉理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,我国铝型材加工产业快速发展,铝型材的应用已从建筑行业,拓展到汽车、船舶、电力和航空航天等领域,铝型材的产量也节节攀升,位居世界第一。铝合金型材具有质量轻、耐腐蚀和比强度高的优异物理、化学性能,某些情况下可替代钢材作结构材料使用,能推动和建设绿色、节能、环保的现代化社会。然而,目前许多铝加工企业的生产技术仍然落后,产品质量不能满足当前社会发展对铝型材提出的较高的要求;并且,铝型材的挤压模具的设计至今还缺少一个系统、完整的理论体系,工程师在设计时多依赖个人的实际经验,并需要在生产中反复修模、试模去验证。因此,研究铝合金型材的挤压成形规律、工艺及其模具设计对提高铝合金产品质量、缩短开发周期和降低企业成本具有重要意义。本文以某一复杂薄壁空心异形铝型材为例,通过对其截面形状、尺寸特征的分析,确定了其适用的挤压模具类型,并完成了分流模具的结构设计和三维建模,并通过强度校核。利用HyperXtrude专业挤压模拟软件对其稳态挤压过程进行了模拟,得到了挤压模具应力、位移分布,揭示了分流挤压模具在挤压过程中受力和变形规律,并以降低模具载荷、减少模具弹性变形为目标,对影响挤压过程的主要工艺参数(挤压速度、坯料预热温度、挤压筒预热温度和模具预热温度)进行了的正交试验,得到了挤压模具应力、应变处最佳状态的工艺参数组合。根据挤压过程模具之中流动金属的温度分布、应力应变分布、速度与变形分布,描述了金属在挤压过程中的变形机理并应用于改进模具结构设计,通过添加阻块、调整工作带的方法对挤压模具进行了改进,使型材截面各点出口流速均匀。针对挤压分流模具的结构特点,将其归纳为五种结构特征,按照自下而上建模的二次开发方法,利用UG/Open UIStyler编辑器设计挤压分流模具设计对话框;利用NXOpen的日记功能录制建模流程,并对其编辑修改实现了挤压分流模具的交互式设计;利用UG/Open Menuscript设计了挤压模具专用的下拉菜单,使分流模具CAD系统与NX融为一体。最后进行实例建模,验证了系统的可行的性。
[Abstract]:In recent years, the aluminum profile processing industry in China has developed rapidly. The application of aluminum profile has been extended from the construction industry to the fields of automobile, ship, power and aerospace, and the output of aluminum profile has also been rising. Aluminum alloy profiles have excellent physical and chemical properties of light weight, corrosion resistance and high specific strength. They can be used as structural materials instead of steel in some cases, and can promote and build green and energy saving. However, the production technology of many aluminum processing enterprises is still lagging behind, and the quality of the products cannot meet the higher requirements for aluminum profiles put forward by the current social development. The design of extrusion die for aluminum profile is still lack of a system, a complete theoretical system. Engineers rely on personal practical experience in the design, and need to repeatedly repair the die in production, to test the mold to verify. It is of great significance to study the extrusion forming law of aluminum alloy profile and its process and die design to improve the quality of aluminum alloy products, shorten the development period and reduce the cost of the enterprise. This paper takes a complex thin-walled hollow shaped aluminum profile as an example. Based on the analysis of the shape and size characteristics of its cross section, the suitable extrusion die type is determined, and the structure design and 3D modeling of the split die are completed. Through strength checking, the steady extrusion process is simulated by HyperXtrude software, the stress and displacement distribution of extrusion die is obtained, and the law of stress and deformation of shunt extrusion die during extrusion process is revealed. With the aim of reducing the die load and reducing the elastic deformation of the die, the orthogonal experiments were carried out on the main technological parameters (extrusion speed, preheating temperature of the billet, preheating temperature of the extrusion tube and preheating temperature of the die) that affected the extrusion process. According to the temperature distribution, stress-strain distribution, velocity and deformation distribution of the flowing metal in the extrusion die, the optimum process parameters of stress and strain of extrusion die are obtained. The deformation mechanism of metal in extrusion process is described and applied to improve the design of die structure. The extrusion die is improved by adding block and adjusting working band. According to the structure characteristics of extrusion split die, it is summarized into five structural characteristics, according to the secondary development method of bottom-up modeling, the UG/Open UIStyler editor is used to design the dialogs of extrusion split die design. The modeling process is recorded by the diary function of NXOpen, and the interactive design of extrusion shunt die is realized by editing and modifying it, and the pull-down menu of extrusion die is designed by UG/Open Menuscript. The CAD system is integrated with NX. Finally, the feasibility of the system is verified by example modeling.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG379

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