ls-dyna模拟子弹侵彻复合装甲，子弹撞击陶瓷层后反弹，是什么原因？ 20
小弟现在是在模拟子弹打击复合装甲的过程，装甲的结构是由陶瓷层、粘贴层和背板组成。最开始，我将子弹的材料定义为*MAT_PLASTIC_KINEMATIC（来源于已有资料），分别改变陶瓷层的厚度，研究子弹的侵彻情况。当陶瓷层的厚度增加到一定厚度时（1.2cm），子弹就会反弹。如下图，
同时，小弟在翻看文献时，发现也有人直接将子弹设为*MAT_RIGID，忽略掉子弹撞击时的质量损失和变形，于是小弟也试了一下，发现效果良好，子弹直接击穿了复合装甲。
于是小弟就很好奇，如果是子弹材料设定的不同引起的结果，为什么同学采用*MAT_PLASTIC_KINEMATIC，并没有出现反弹的现象（他是使用的三层陶瓷复合，但是总厚度与我相差不远），而是一直保持侵彻直至抵达背板。
附上小弟的k文件：
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你的单位制是什么？感觉单位制有些混乱