Enhanced Thermal Stability in Nanostructured Bainitic Steel

We report an attempt at increasing the thermal stability of nanocrystalline bainite to tempering heat-treatments, by enhancing the silicon concentration of the alloy. Validation experiments have been conducted using synchrotron X-radiation during tempering heat treatment. It is found that the change in alloying successfully stabilises the austenite at elevated temperatures by retarding cementite formation to temperatures as high as 500C. Other changes reflected in the lattice parameters of the major phases have revealed further information about the mechanisms involved.