Effect of Strike Face Geometry on the Dynamic Delamination of Composite Back Plates.

摘要

Ceramics are often employed as a hard strike face in composite armor systems. The ceramic serves to break up and erode the penetrator while the back plate absorbs the kinetic energy of the remaining penetrator material. In this program, soda lime glass was used as a surrogate for ceramic to investigate how the strike face geometry affects composite back plate delamination. Understanding how the strike face design influences damage in the armor is an important consideration for multihit requirements. The test specimens were composed of a soda lime float -glass strike face that was adhered to an S-2 glass composite back plate using a transparent adhesive. A 0.30- cal. fragment-simulating projectile was used to ballistically interrogate the specimens, thereby introducing areas of delamination in the backing plate. The inherent translucency of the test specimen allowed for capture of dynamic delamination images with high-speed photography. The projected delamination area was quantified using commercially available digital image analysis software. The effects of glass thickness, geometry, and hit location were studied. It was found that an increase in the strike face diameter resulted in an increase in delamination area and an increase in delamination growth velocity. It was also found that projectile impacts at seam locations between 2 tiles result in more delamination than projectile impacts on the tile center or triple point of the strike faces. These are significant results because they run counter to some of the commonly held beliefs in the armor community.