13Cr Martensitic Stainless (var. 5)

13Cr Martensitic Stainless Steel (variant 5) is a precipitation-hardened martensitic stainless steel with elevated cobalt and silicon content, designed to achieve high strength through age-hardening treatment while maintaining corrosion resistance typical of 13% chromium steels. This variant is primarily used in aerospace and defense applications where a combination of high strength, corrosion resistance, and moderate toughness is required, particularly in fasteners, turbine components, and structural elements exposed to moderately corrosive environments. The cobalt and molybdenum additions enhance strength and fatigue performance compared to conventional 13Cr martensitic grades, making it competitive with nickel-based alternatives in weight-sensitive applications where cost and machinability are considerations.