Tool Steel H11

Principal Design Features

This alloy is one of the Hot Work, Chromium type tool steels. It is relatively low in carbon content and has good toughness and deep hardens by air quench from heat treatment.

Applications

H11 is often used for highly stressed structural parts such as aircraft landing gear. It resists softening at temperatures up to 1000 F while retaining good ductility and toughness even at strength levels on the order of 275 ksi.

Machinability

Machinability is reasonably good, approximately 75% that of the W group water hardening low alloy tool steels.

Forming

Forming characteristics of H11 are good by conventional methods. It also may be formed by forging and machining.

Welding

H11 is a readily weldable alloy by conventional methods.

Heat Treatment

Preheat to 1500 F and then heat to 1850 F and hold for 15 to 40 minutes. Air cool (air quench).

Forging

Forge at 2050 F down to 1700 F. Do not forge below 1650 F.

Hot Working

No data given. The alloy may be hot worked by “Forging”.

Cold Working

Cold working may readily be accomplished on H11 by conventional methods.

Annealing

Anneal at 1600 F and slow cool at 40 F per hour or less in the furnace.

Aging

Not applicable to this alloy.

Tempering

Temper at 1000 F to 1200 F for Rockwell C hardness of 54 to 38. Double tempering for one hour each time at the selected tempering temperature is recommended.