The US Army Research Laboratory is working on developing new light-weight ceramic materials that resist fracture, and has teamed with researchers from the University of Florida to better understand exactly how these materials, which are suited for Soldier personal protection and Army systems, fracture, and how they can be further improved. They are focusing on failure through cracking; the material eventually disintegrates into a granular-like state through a process called comminution.
"While various ceramic materials possess high hardness, they fail easily when pulled apart. That is, when subjected to tensile forces. The amount of tension that these materials can withstand before failure, is a small fraction of the compression they can withstand. As a result, high velocity impact of bullets and fragments causes extensive cracking and fragmentation of the material, reducing its ability to fully utilize its superior hardness to resist complex stress states generated by the impact event," explained Dr. Sikhanda Satapathy, of ARL's Soldier Protection Sciences Branch.