Patent ID: 7967927

Claim:
A method of producing a structural, stainless steel alloy comprising the steps of: (a) combining a mixture in weight percent in a melt of about 0.15 to 0.30% carbon (C), about 8 to 17% cobalt (Co), about 2.0 to 10.0% nickel (Ni), about 8.0 to 11.0% chromium (Cr), about 1.0 to 3.0% molybdenum (Mo), less than about 0.8% vanadium (V), and less than about 3% tungsten (W), the balance essentially iron (Fe) and incidental elements and impurities; and (b) processing said melt mixture to form an article of manufacture characterized in that the alloy has a predominantly lath martensite microstructure essentially without topologically close packed intermetallic phases and said carbon (C) is in predominantly a dispersion of nanoscale, M 2 C carbide particles having a nominal dimension less than about 10 nanometers in diameter, where M is two or more elements selected from the group consisting of Cr, Mo, W, V, Nb and Ta, and the alloy is processed to an ultimate tensile strength greater than about 260 ksi.