Ballistic Steel Plates that are typically an alloy comprised of iron with titanium (and aluminum, nickel, and iron) are the most common choice of opaque material applied in armoring vehicles.
Ballistic Steel
Ballistic glass is an important part of armored vehicles. It is tested to make sure it stays strong under tough conditions. Live-fire tests check how the glass holds up against multiple shots and different temperatures, even when the glass is older and shows signs of wear.
Ballistic Composites
Ballistic composites like polyethylene, aramid fiber, and ceramics are sometimes added to select SUVs and sedans after testing their strength. These materials are tested to see how well they hold up against high-power rifles under different conditions.