High tensile steel
Alternative term: High yield steel
Steel having a higher tensile strength than mild steel, containing up to 0.3 % carbon, 0.5 % copper, and 1.5 % manganese, or other metals.
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM