H11/1.2343 tool steel is a 5% chromium hot work steel that is characterized by excellent impact toughness. It contains less vanadium than the widely-used H13 tool steel. This provides for the higher toughness, with some reduction in wear resistance and temper resistance. H11 tool steel is a deep-hardening, air-hardening steel that exhibits minimal size change during heat treatment. The steels are subjected to minimal distortion during hardening due to their balanced alloy content. It has good resistance to thermal fatigue cracking (heat checking) and excellent resistance to gross cracking and thermal shock when water cooled in service. H11 tool steel is recommended for hot tooling applications where maximum resistance to cracking is required. Such applications include hot punches, die casting dies, forging dies, hot shear blades, hot gripper dies, and extrusion tooling.