【作者】 王宇；

【导师】 刘立君；

【作者基本信息】 哈尔滨理工大学 ， 材料加工工程， 2015， 硕士

【摘要】 内高压成形工艺已经随着汽车制造业的发展得到了迅猛的发展，其具有新型近净的柔性加工工艺得到了制造业的认可。内高压成形工艺在汽车领域的快速发展，使得对于焊接后的管坯进行内高压胀形技术的得到了广泛的应用，这同时是一个难点，因此对于焊接后的管坯进行了内高压胀形技术研究，具有十分重要的意义。本文以消音管为研究对象，通过理论分析、数值模拟和实验相结合的方法，对消音管的胀形过程做了研究。利用有限元分析软件DYNAFORM，分析了成形过程中焊缝附近应力的变化，对比了三种不同的加载路径对消音管成形质量的影响，并且进行了消音管成形工艺实验与分析，最终确定了凹形曲线的加载路径为最优加载路径。为了能够更为深入的研究消音管胀形过程中，焊缝附近应力的变化,本文又采用了MARC有限元分析软件对消音管的胀形过程进行了有限元模拟分析，MARC有限元分析软件相对于dynaform软件在焊缝附近的模拟效果更好。分析了内高压成形过程中初步成形阶段、贴膜阶段和胀形结束阶段中，焊缝附近等效应力的变化情况。把与消音管内高压成形的实验结果进行对比验证，得到在消音管进行内高压胀形的过程中，焊缝及焊缝附近的热影响区所受到的等效应力为最大，此位置也最易出现断裂。更多还原

【Abstract】 Internal high-pressure forming technology has obtained the swift and violentdevelopment along with the development of the auto industry. As a new type of cleanand flexible process, Internal high-pressure has got the recognition of manufacturing.As internal high pressure forming technology developing rapidly in the automobileindustry, the welded tube billet in high pressure bulging technology has been widelyused which is also a difficult point at the same time. Therefore, it is of vitalimportance to research the welded tube billet in high pressure bulging technology.The paper researches the bulging process of the mute tube which based ontaking the mute tube as the research object through the method of combiningtheoretical analysis, numerical simulation and experiment. With the help of the finiteelement analysis software-DYNAFORM, the paper analyzes the variation of thestrain near the weld in the forming process and compares the impact of the threedifferent loading paths on the quality of the sound tube forming. This paper alsoresearches the experiment and analysis of the forming process of tube and finallydetermines the loading path of the concave curve is the optimal one.In order to do the further studies on the changes of the strain near the weld inthe bulging process of the mute tube, this paper uses the marc software to analyze thebulging process of the mute tube with simulating the finite element. The results ofusing the marc software to analyze finite element is better than the one withdynaform. This paper analyses the changes of equivalent strain near the weld duringthe process of internal high-pressure forming, including the preliminary formingstage, the laminated stage and the bulging end stage. By comparing with theexperimental results of internal high pressure forming process of the mute tube, theequivalent stress on the weld and heat affected zone near the weld in the process is the bigger one. And this position is also the most prone to fracture.更多还原