A high-nickel, molybdenum-strengthened low-alloy steel designed for cryogenic and ultra-high-strength structural applications, where the elevated nickel content (17.5%) combined with molybdenum hardening and trace titanium provides both toughness at low temperatures and significant strength in the gigapascal range. This material family is primarily encountered in aerospace and defense sectors—particularly for landing gear, rocket casings, and deep-sea pressure vessels—where the combination of low-temperature impact resistance and high yield strength outweighs the cost and machinability trade-offs versus conventional steels. The low carbon content and nickel-molybdenum matrix chemistry make it notably more fracture-resistant than martensitic high-strength steels at equivalent strength levels, making it the preferred choice when cryogenic service or repeated shock loading is a design driver.
Compliance & Regulations
| Property | Value | Unit | Conditions | Source | |
|---|---|---|---|---|---|
Elongation at Break(εf) | 10.70 | - | — | ||
Ultimate Tensile Strength(σUTS) | 248 | ksi | — | ||
Yield Strength (0.2% offset)(σy) | 238 | ksi | — |