力约束管材自由胀形试验研究与材料性能测试  

Tube free bulging experiment with force-end and material properties testing

作　　者：程鹏志[1] 郎利辉[1] 葛宇龙[1] 阮尚文[1] 王韬 武海 

机构地区：[1]北京航空航天大学机械工程及自动化学院,北京100191 [2]上海汇众汽车制造有限公司,上海200122

出　　处：《北京航空航天大学学报》2015年第4期686-692,共7页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家"973"计划资助项目(613152);国家自然科学基金国际(地区)合作与交流资助项目(51111120088)

摘　　要：相较于单向拉伸试验,通过管材胀形试验(TBT,Tube Bulging Test)获得的材料性能参数能够更准确地反映材料在高压流体作用下的塑性成形性能,不同的管端边界将会严重影响管材胀形试验的测试结果.针对国际上现有试验方法和设备存在的不足,研制出了一套约束边界清晰、加载精确的管材自由胀形试验系统.在管材测试过程中,基于位移随动力主动加载的控制策略和比例伺服油缸,实现实时的轴向力、轴向位移和内压力的精确加载.端部约束的测试管材通过特殊设计的工装保证了其轴向自由滑动.实时内压力和胀形管材顶点处材料的壁厚和胀形高度信息通过超高压压力传感器、超声测厚仪和磁致伸缩位移传感器采集,进而基于Swift材料本构模型和采集到的数据拟合出材料应力应变曲线和材料性能参数.试验结果表明,管材两端侧推力与内压力对管材内腔端面的作用力和管材轴向自由对称收缩的平衡条件始终处于动态稳定中,试验设备能够准确获得实时胀形高度、顶点厚度、轴向收缩长度和内压力的信息,能够为材料性能测试和工艺设计提供可信的材料参数.Compared with uniaxial tension, the material property parameters obtained by tube bulging test （TBT） can accurately reflect the plastic forming properties of materials under high-pressure fluid condition. Different end-conditions will seriously affect the experiment results of TBT. According to the defects of existed experimental method and equipment internationally, a special TBT system, with accurate boundary conditions and loading units, was successfully designed and developed. The axial force, axial displacement, and the internal pressure are the key points of the system which could be accurately controlled in real-time hyeontrol strategy of displacement under dynamic active loading state and proportional servo valves. The free sliding of fixed tube ends was implemented by a special designed fixture. During the experimental process, the real-time thickness and bulging height in the pole, and the real-time internal pressure were monitored by the uhrasonie thickness gauge, the magnetostrietive displacement sensor and the ultra-high pressure sensor. The stress-strain curve and material properties were derived by the Swift material constitutive model and the monitor data. The experimental data demonstrate that the two load balance conditions, which are the balance of two axial forces with internal pressure and the balance of two axial contractive displacements, are always satisfied during all the test process. The test data processing results show that the monitor data have good repeatability and can be used to get the material properties.

关 键 词：充液成形 胀形试验 管端边界 自由滑动 轴向力 内压力 胀形高度 材料参数 

分 类 号：V261.28[航空宇航科学与技术—航空宇航制造工程]