Abstract: A high strength, high toughness glass coated steel composite material is provided which exhibits greatly increased ballistic properties over the uncoated steel. A borosilicate glass coating is fused onto the surface of the steel in a process which heats the steel and an aqueous slurry of the borosilicate glass to a temperature which is suitable for both fusing the glass to the steel and for providing a heat soak for the steel to air harden the steel to a hardness suitable for a ballistic steel. The nickel content of the steel promotes the bonding strength of the glass coating to the steel, and the borosilicate glass may contain a cobalt additive to also promote increased bonding strength.