钨钛混合粉末爆炸压实的数值仿真

Numerical Simulation of Explosive Compaction of W-Ti Powder

在利用叠加原理对钨钛混合粉末参数进行计算的基础上,借助于LS-DYNA 3D有限元程序,并采用带罚函数的滑移接触算法对钨钛混合粉末的爆炸压实过程进行了数值仿真.通过改变装药比(E/M),得到了压实试件中的压力云图,轴线上选定单元的压力时程曲线,中心截面选定单元的压力时程曲线、中心截面选定节点的径向位移曲线;对钨钛粉末进行了爆炸压实试验,借助于宏观照片对爆炸坯截面中心的马赫孔进行了观察分析.结果表明:随着装药比的增大,试件密度呈增大的趋势,但装药比过大,会在压实件中产生马赫孔,致使压实质量下降,装药比是影响压实质量的重要参数.数值仿真与试验结果吻合良好.

Based on the counting of the parameters of the W-Ti mixed-powder by the superposition principle,numerical simulation for the process of the explosive compaction of W-Ti mixed-powder was presented by means of the FE code of LS-DYNA and the algorithm of sliding contact with penalty was adopted.Pressure nephogram of the set-up for explosive compaction,pressure time-history curve of the certain elements of the axis of the sample,pressure time-history curve of the certain elements of the center cut and its radial displacement curve of the certain nodes were obtained by changing the value of charge ratio（E/M）.The experiment of explosive consolidation for W-Ti powder was carried out and observed the mach hole on the center of the samples section recur to the macrograph.The result shows that the density of the sample was apt to increase with the increasing of the value of E/M,but if the value of E/M is too large,the mach-hole will appear in the sample,which debases the compact quality.The charge ratio is an important parameter which affects the compact quality.The result of the experiment agrees with that of numerical simulation.