Special treatment steel (STS) is a high-tensile, nickel-chromium steel alloy engineered to resist ballistic impacts without shattering. Unlike face-hardened armor, special treatment steel is heat-treated to have uniform hardness and ductility throughout its entire thickness. This allows it to absorb the kinetic energy of heavy projectiles by deforming rather than cracking.
Heard on the job
The deck plating calls for two inches of STS to protect the steering gear from plunging fire.
Also heard as
- Special treatment steel