金属厚靶的超高速碰撞开坑实验

CRATERING EXPERIMENTS WITH HYPERVELOCITY IMPACT UPON THICK METALLIC TARGETS

介绍了对高速球形弹丸撞击金属厚靶的开坑现象所进行的实验研究。最高弹速为7.5km/s；弹靶材料有7种组合：硬铝打硬铝，钢打钢，黄铜打黄铜，钢打硬铝，硬铝打钢，钢打纯铜和硬铝打铅。用量纲分析归纳前6种（即铅靶除外）情况，得到坑深P和弹径D。之比值的经验关系是其中v是弹速，Pp和Pt是弹和靶的材料密度，Yt是靶板材料的动态屈服强度。铅靶因为容易产生熔化和气化，且可压缩性好，故坑深实验值比上式的计算值高得多。对于一定的弹靶材料的组合，增加弹速则坑形趋向于半球形。

The phenomenon of cratering during a hypervelocity impact of a spherical projectile upon a thick metallic target has been investigated experimentally,the highest velocity of projectile experiment with being 7.5km/s.Seven sets of projectile-target material combinations were used.An empirical relationship is deduced from the experimental data,where P represents the penetration depth,D p the crater diameter,Pp and P1 the density of projeetile and target material respectively,and Y1 the dynamical yield strangth of target material.The shape of the crater changed rapidly as the velocity increased,toward a roughly hemi-spherical shape for certain projectile-target material combinations.