Patent ID: 7875565

Claim:
A composite armor system wherein a glass-ceramic element or material constitutes at least one component, said glass-ceramic material having crystallites of size 30 nm or less and a ballistic limit vs. areal density line slope of 1.2 or greater; wherein: said glass-ceramic material is a β-quartz glass-ceramic having a crystallinity of 50 Vol. % or greater, and said glass-ceramic material has a composition comprising, in weight percent, Component Wt. % SiO 2 65-70 Al 2 O 3 17-23 Li 2 O 2.5-4 MgO 0-3. ZnO 0-3 TiO 2 2-4 BaO 0.5-2 SrO 0-.5 ZrO 2 1-2 As 2 O 3 1 Sb 2 O 3 0 Na 2 O 0.2 K 2 O 0.2 V 2 O 5 0 all weight percents being ±10% of the given weight percent amount.