THE EFFECT OF COVERPLATES ON THE DWELL CHARACTERISTICS OF SILICON CARBIDE SUBJECT TO KE IMPACT

摘要

The high ballistic efficiency of non-oxide ceramics such as silicon carbide against kinetic energy (KE) threats is largely due to penetrator dwell (the erosion of the tip of the rod prior to ceramic target penetration). This paper considers the effect of target surface conditions on the dwell characteristics of silicon carbide. This has been investigated using a range of cover plate (CP) designs impacted at normal incidence with a 5mm-diameter tungsten rod of 20:1 aspect ratio, over the velocity range 1100m/s to 1900m/s. Significant behavioural transition regions have been identified. In the velocity range 1330-1630 m/s the use of coverplates increases the Em significantly. There is a significant stepwise decrement in Em for targets with cover plates when impact velocities exceed a velocity of 1600m/s. At velocities in excess of 1700m/s there is a gradual decrease in Em with increasing velocity compared to targets without coverplates to the point where the use of coverplates is positively detrimental.