弹载加速度记录仪在冲击环境下的失效研究

摘要

在弹体侵彻过程中,首先分析高g值冲击对弹载加速度记录仪的影响,得出应力波作用下加载到弹体内记录仪的加速度值,并研究了加速度记录仪壳体、缓冲材料及电路板的动态结构响应,进而提出可能出现的失效模式:壳体结构的失效、缓冲材料缓冲性能的不足、芯片与PCB板相对运动导致芯片的裂纹.针对各失效模式,利用ANSYS/LS-DYNA对记录仪各防护单元进行了数值模拟仿真,得出各防护单元失效的临界冲击加速度值:电路板失效的临界冲击加速度为1.93×104 g,当加载冲击加速度为1.63×105 g时,壳体发生屈曲；增大冲击加速度至5.63×106 g时,缓冲材料失效.经过实弹侵彻试验,得出记录仪在1.5 x105 g的冲击加速度下失效.该实验结果对后续弹体实际侵彻弹载记录仪的设计及优化提供数据支撑.%In a projectile penetrating process,the influence of a high g shock on a missile acceleration recorder was analyzed,and the recorder acceleration values under action of shock stress wave were obtained.The dynamic structural responses of the acceleration recorder shell,buffer material and circuit board were studied and the failure modes to possibly appear including failure of shell structure,buffer material performance insufficiency,and chip cracking due to relative motion between chip and PCB board were presented.For each failure mode,the dynamic behavior of each protection unit of the recorder was numerically simulated with ANSYS/LS-DYNA,then,the each protection unit failure critical acceleration was obtained.It was shown that the circuit board failure critical acceleration is 1.93 × 104 g; the shell buckles when the impact acceleration is 1.63 × 105 g; when the impact acceleration rises to 5.63 × 106 g,the buffer material fails.After real ammunition penetration tests,it was observed that the recorder fails under 1.5 × 105 g impact acceleration.The test results provided data support for the design and optimization of a missile acceleration recorder during subsequent projectile actual penetration.