An improved high-strength, high-toughness steel has been developed which shows considerable promise for landing gear applications. Previous materials provided high strength or high toughness, but not both. The improved material is a modified chemistry of AF1410 steel with increased carbon and an altered heat treat process. Tensile ultimate strengths (Ftu) of over 260 ksi (1.79 GPa) have been achieved while maintaining plane strain fracture toughness (Klc) in excess of 100 ksh/inch (110 MPa√m). In addition, the material has low sensitivity to environmental factors such as hydrogen embrittlement and stress corrosion cracking.
