Effects of Partial Replacement of Si by Al on Impact Toughness of 0.2%C-Si-Mn-Cr-B TRIP-Aided Martensitic Steel

The effects of partial replacement Si by Al on the microstructure, tensile properties, and Charpy impact toughness were investigated using 0.2%C-Si/Al-Mn-Cr-B TRIP-aided martensitic steels to promote application galvanized third-generation ultrahigh- high-strength steels. was related microstructural mechanical properties. decreased volume fraction retained austenite increased stability, accompanied softening an increase in primary martensite. Resultantly, strength ductility. absorbed energy (value) at 25 °C slightly replacement. mainly caused high crack/void propagation due softened martensite a small contribution stabilized austenite. 50% shear fracture ductile-to-brittle transition temperature marginally raised associated with unit crack path quasi-cleavage/cleavage fracture.