基于加工量的无芯模旋压旋轮轨迹规划与进给比优化研究

发布时间：2018-04-01 03:07

本文选题：无芯模旋压　切入点：轨迹规划　出处：《浙江大学》2017年硕士论文

【摘要】：在金属塑性成形领域,旋压作为一项特殊的加工工艺,因其具有无屑加工、产品精度高、功耗低等优点而越来越多的受到关注。本文针对无芯模旋压中加工量的表征方式存在的不足,首先对本课题组提出的弯曲量和环向应变量两种加工量在旋轮轨迹规划和变进给比方面进行对比,分析两者各自的优缺点,然后根据两种加工量推导出综合加工量,最后基于综合加工量进行轨迹规划和变进给比研究,并验证了基于综合加工量的轨迹规划和变进给比方法的有效性。本文分为六章,主要内容如下:第一章介绍了旋压的加工方法,并阐述了无芯模旋压的研究背景和意义,列出了无芯模旋压技术的国内外研究现状,给出了本文的主要研究内容和组织框架。第二章列举出了本课题组提出的两种加工量表征方式——环向应变量和弯曲量,介绍了本文所用的实验结合仿真的研究方法,给出了实验的平台和相关工艺参数,总结了旋压仿真中所用的有限元显式动力学理论并给出了仿真软件中相关参数的选取。第三章对基于两种不同加工量的轨迹规划与成形质量关系进行对比研究。控制理想形状曲线和工艺参数一致,分别设计各道次等弯曲量和等环向应变量的轨迹规划实验,得出等弯曲量的轨迹规划方式较等环向应变量的规划方式形状精度更高而壁厚减薄更严重的结论;在两种加工量的表征下,通过提高终道次的加工量占比进行轨迹规划优化,基于环向应变量的优化方法较弯曲量的优化方法对形状精度的提高幅度更大。第四章对基于两种不同加工量的旋轮变进给比与成形质量关系进行对比研究。控制理想形状和加工总时间相同,分别设计各道次等平均弯曲量变化速度和等平均环向应变量变化速度的道次间变进给比实验与终道次等弯曲速度和等环向应变进给比的道次内变进给比实验,得出基于弯曲量的道次间和道次内变进给比较基于环向应变量的变进给比方法得到的形状精度更高而壁厚减薄更严重的结论;在两种加工量的表征下,通过提高终道次的加工时间占比进行道次间变进给比优化以及提高道次内变进给比的道次数进行道次内变进给比优化,结果显示基于弯曲量的道次间和道次内变进给比优化方法较基于环向应变量的变进给比优化方法得到的形状精度更高而壁厚减薄更大。第五章提出了基于综合加工量的轨迹规划和变进给比方法。根据弯曲量和环向应变量推导出综合加工量的公式,基于等综合加工量进行旋轮轨迹规划,并通过终道次综合加工量占比的提高进行轨迹规划优化,结果显示基于综合加工量的轨迹规划和优化方法得到的形状精度高于基于弯曲量的方法且抑制了壁厚的减薄;基于等综合加工量变化速度进行道次间和道次内变进给比以及通过终道次加工时间占比提高进行道次间变进给比优化和道次内变进给的道次数提高进行道次内变进给比优化,得出基于综合加工量的变进给比方法在有效抑制壁厚减薄的前提下能大幅提高形状精度的结论。第六章总结了本文的主要研究成果,并指出了研究中存在的不足,对下一步的研究进行展望。
[Abstract]:In the field of metal forming, spinning as a special process, because of its non chip processing, high precision, low power consumption and more and more attention. Deficiency of the characterization method for machining mandreless spinning in quantity, first proposed on this topic group and bending ring to be two kinds of processing capacity in variable roller trajectory planning and variable feed ratio were compared, analysis the advantages and disadvantages of the two, and then derive the comprehensive processing capacity of two according to the amount of processing, and finally the trajectory planning and variable feed ratio of comprehensive processing capacity based, and verifies the validity of the trajectory planning and change feed volume ratio method based on comprehensive processing. This paper is divided into six chapters, the main contents are as follows: the first chapter introduces the processing method of spinning, and expounds the mandreless spinning research background and significance, lists the mandreless spinning technology The research status at home and abroad, this paper gives the main research content and framework. The second chapter lists the research group presented two kinds of representation - processing capacity of circumferential strain and bending, introduces the experimental research method combined with simulation, gives the experimental platform and the related technical parameters and summarizes the finite element simulation by spinning in explicit dynamics theory and gives the selection of related parameters in simulation software. The third chapter is the comparative study of the trajectory planning of two different processing capacity based on forming quality control. To shape curve and process parameters, designed for each passes and bending ring to be experimental trajectory planning variables, the way of trajectory planning is bending ring to be planning the shape precision and variable wall thickness is more serious in conclusion; two Characterization of processing amount, by improving the final pass processing accounted for the trajectory planning optimization based on loop optimization method of bending should be variable optimization method of the amount of shape accuracy greatly. The fourth chapter comparative study on two kinds of different processing capacity based on variable feed ratio and forming roller at the same time to control the total quality of the relationship between the shape and design of the ideal processing, respectively passes the average speed and average change of bending ring to strain the change speed of a variable feed ratio experiment and the end times, the bending speed and circumferential strain feed ratio passes variable feed ratio experiment that passes the amount of time between bending and internal variable feed comparison based on ring shape to the precision of variable feed variable ratio method is more effective and more severe wall thinning based on the conclusion; in the characterization of two kinds of processing amount, by improving the final pass The processing time of a variable proportion of feed increased optimization and variable feed ratio passes the number of road passes variable feed ratio optimization, results based on the amount of secondary bending between the road and pass in variable feed ratio optimization method based on ring shape precision strain variable feed ratio optimization method to get the higher wall thickness is larger. The fifth chapter puts forward the trajectory planning and comprehensive processing capacity based on variable feed ratio method. To strain derived comprehensive processing formula according to the quantity and amount of bending ring, based on the comprehensive processing capacity of cycloid trajectory planning, and the final pass through comprehensive processing the amount of the increase of the trajectory planning and optimization results show that the precision of shape, trajectory planning and optimization method based on the comprehensive processing capacity is higher than the method based on the amount of warping and restrain wall thickness; based on the changes of processing speed The degree of pass and pass in the final pass through the feed ratio and increase the proportion of processing time interval time varying feed ratio and improve optimization passes the channel number of variable feed passes variable feed ratio optimization, the comprehensive processing capacity based on variable feed ratio method to restrain the wall the thinning of the premise can greatly improve the shape accuracy of the conclusion. The sixth chapter summarizes the main research results, and points out the shortcomings of the study, the next research is prospected.

【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG306

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