摘要
磁脉冲成形是利用磁压力对金属坯料进行塑性加工的高能、高速率加工方法,与常规成形工艺相比有诸多优点,为高强度、难成形材料开辟了新的成形加工途径。而瞬时近似正弦衰减的脉冲磁压力和不均匀起皱变形,使圆管磁脉冲缩径压缩失稳判据研究非常棘手。文章选择王仁提出的冲击屈曲能量准则进行此塑性屈曲判据研究。首先,应用该能量准则确定冲击载荷作用下圆管产生塑性屈曲的临界冲击能量;然后,通过使临界冲击能量与磁压力脉冲第一波对工件变形和运动做功相等,建立圆管产生径向塑性压缩失稳的临界判据。研究表明,产生径向屈曲塑性变形的临界放电电压随径厚比增加而提高,其试验值与判据确定的理论值吻合较好。应用该判据能够预测使圆管产生失稳屈曲的临界放电电压(能量),使均匀径向塑性变形的定量分析成为可能。
The researches on the plastic buckling criterion of magnetic pulse tube compression has been hindered by the waveform of pulsed magnetic pressure that is quasi-sinusoidal attenuating instantaneously and the inhomogeneous compressing buckling. The impact buckling energy criterion proposed by Wang Ren is chosen for the establishment of the plastic buckling criterion. Firstly, the critical impact energy for the plastic buckling of the tube under impact load is determined by the energy criterion. Then, the plastic buckling criterion, which can be used to determine the critical discharge voltage （energy） for the tube compression buckling, is established by equaling the work applying on the tube deformation and motion by the pulsed magnetic pressure to the critical impact energy. The results show that the experimental value of the critical voltage for the radial plastic buckling agrees well with the theoretical one according to the buckling criterion, and both values increase with the increasing ratio of tube radius to its wall thickness.
出处
《塑性工程学报》
EI
CAS
CSCD
北大核心
2008年第5期121-126,共6页
Journal of Plasticity Engineering
基金
国家自然科学基金面上资助项目(50575052)
关键词
冲击屈曲能量准则
塑性失稳判据
磁脉冲缩径
放电电压(能量)
impact buckling energy criterion
plastic buckling criterion
magnetic pulse tube compression
discharge voltage（energy）
