4340 HR Annealed AQ
Chemical Composition
Carbon:                 0.38%-0.43%
Nickel:                   1.65%-2.00%
Chromium:              0.70%-0.90%
Manganese:            0.60%-0.80%
Molybdenum:           0.20%-0.30%
Silicon:                   0.15%-0.35%
Sulfur:                    0.025% Max
Phosphorous:           0.025% Max
4340 AQ is typically bought to meet chemistry requirements rather than physical requirements. For that reason, physical properties are generally not provided unless requested prior to production. Any material can be sent to a third party after production to be tested for physical properties.
Typical Uses
Typical uses for 4340 include:
  • Landing Gears
  • Power Transmission Gears
  • Shafts

4340 Hot Rolled Annealed Aircraft Quality

Alro Stocks AISI 4340 HR AQ - a highly alloyed steel with high nickel and chromium content which assures deep hardening when oil quenched, with high strength characteristics throughout the section. Used for heavily stressed parts operating under strenuous conditions.