H11 tool steel
The H series of steel is start from H1 to H21.
chromium hot-work tool steels appoint as group H steels.
H11, H12, H13 steel are most commonly used chromium hot-work steels.
H11, H12, H13 steel may air hardened in 150 mm thick section.
The tools constructed from chromium hot-work steels may cooled with the help of water without any damage as these steels have less alloy contents and carbon.