H11 is a 5% chromium hot work tool steel characterized by its incredible impact toughness. The alloy is a deep-hardening, air-hardening steel which takes place through heat treatment and air-quenching.

Because of its excellent resistance to thermal fatigue cracking, in addition to strong resistance to gross cracking and thermal shock, H11 is generally used in highly stressed structural parts such as aircraft landing gear.

Other applications include die casting dies, forging dies, hot punches, hot gripper dies, forging dies, and extrusion tooling.

AMS Spec Application
AMS 6437 AMS 6437 consists of less vanadium than the widely used H13 hot work tool steel.
AMS 6485 AMS 6485 gives minimal size change during heat treatment and the alloy is forged at 2050°F.
AMS 6487 AMS 6487 is a chromium hot-worked steel that is characterized by low carbon content and good toughness.
AMS 6488 AMS 6488 features balanced alloy content, resulting in minimal distortion during hardening.