曲线轮廓零件的切挤复合精整关键技术研究

发布时间：2019-05-12 09:48

【摘要】：切挤复合精整工艺为局部精密轮廓零件的加工提供了新的成形方法,它比切削加工效率高,又比精冲的成本低。本课题旨在对曲线轮廓零件进行切挤复合精整关键技术研究,得出曲线轮廓零件的切挤复合精整工艺规律,并总结一套成形工艺参数规范,为曲线轮廓零件的切挤复合精整加工提供理论指导。本文首先研究了曲线轮廓零件的切挤复合精整变形机理,根据曲线轮廓特征,把精整细分为了内凹轮廓精整和外凸轮廓精整两种类型。研究了切挤复合精整中变形区的划分、变形区的应力应变状态,得到了第三变形区是影响成形质量的核心变形区以及对切挤复合精整工艺有主要影响的工艺参数。其次,研究了相应模拟参数的设置,利用DEFORM-3D软件建立了数值模型,并通过模型分析了内凹轮廓精整和外凸轮廓精整过程,以及分析了精整过程中精整力、材料流动速度场、金属剪切滑移以及变形区应力分布规律,得到了内凹轮廓精整相对于外凸轮廓精整更有利于得到高的成形质量。再次,对影响切挤复合精整工艺的五个工艺参数分别进行分析,得到了它们对成形质量的影响规律。最后,设计制造了内凹轮廓精整和外凸轮廓精整实验模具,通过实验验证了工艺规律的准确性。并且分析了精整后成形零件表面特征,并总结了不同料厚下工件达到全光亮成形面的工艺参数规范。研究表明:主模具圆角、坯料余量和料厚是影响曲线轮廓零件切挤复合精整工艺的最关键工艺参数,它们对精整工艺存在交互影响。本文的研究成果为曲线轮廓零件精整加工奠定了基础,为实际生产提供了很好的参考。
[Abstract]:The cutting and extrusion compound finishing process provides a new forming method for the machining of local precision outline parts, which is more efficient than cutting and lower than the cost of fine blanking. The purpose of this paper is to study the key technology of cutting and extrusion compound finishing of curve outline parts, to obtain the cutting and extrusion compound finishing process law of curve outline parts, and to summarize a set of forming process parameters specification. It provides theoretical guidance for cutting and extruding compound finishing of curve outline parts. In this paper, the mechanism of cutting and extrusion compound finishing deformation of curve outline parts is studied. According to the characteristics of curve outline, the finishing is subdivided into two types: concave profile finishing and convex profile finishing. The division of deformation zone and the stress and strain state of deformation zone in cutting and extrusion composite finishing are studied. The third deformation zone is the core deformation zone that affects the forming quality and the process parameters which have the main influence on the cutting and extrusion composite finishing process are obtained. Secondly, the setting of the corresponding simulation parameters is studied, the numerical model is established by using DEFORM-3D software, and the finishing process of concave contour and convex contour is analyzed by the model, as well as the finishing force and material flow velocity field in the finishing process are analyzed. According to the law of metal shear slip and stress distribution in deformation zone, it is found that concave profile finishing is more beneficial to obtain higher forming quality than convex profile finishing. Thirdly, the five process parameters affecting the cutting and extrusion composite finishing process are analyzed respectively, and their effects on the forming quality are obtained. Finally, the experimental dies of concave profile finishing and convex profile finishing are designed and manufactured, and the accuracy of the process law is verified by experiments. The surface characteristics of the formed parts after finishing are analyzed, and the process parameter specifications for the workpiece to reach the full bright forming surface under different material thickness are summarized. The results show that the fillet of the main die, the blank allowance and the material thickness are the most key process parameters that affect the cutting and extrusion compound finishing process of the curved outline parts, and they have interactive influence on the finishing process. The research results of this paper lay a foundation for the finishing of curved outline parts and provide a good reference for practical production.
【学位授予单位】：重庆理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG306

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