APFIM STUDIES ON MARTENSITE TEMPERING OF FE-C-SI-MN LOW-ALLOY STEEL

The partitioning of manganese and silicon at the cementite/ferrite int erface during the tempering process of Fe-C-Si-Mn martensite has been studied by atom probe field ion microscopy. The results from early sta ges of tempering indicate that cementite can form without partitioning of silicon and manganese and appears to be controlled by carbon diffu sion in the matrix. The onset of a significant redistribution of both silicon and manganese occurs after extended tempering. Two-step temper ing led to extensive partitioning of manganese and silicon.