A GROWTH MANNER OF BUTTERFLY MARTENSITE

The growth of butterfly martensite in an Fe-Ni-V-C alloy was investiga ted using an optical microscope and transmission electron microscope t hrough observing its morphology. The present butterfly martensite is d islocation-type, with a few fine twins. One wing of a butterfly marten site is layered more heavily than the other and the concave part is la yered more obviously than other regions. Most butterfly martensites ha ve a lath plate outside of and next to one wing. The outside martensit e plates grow first, and then two wings of butterfly martensite. The s mooth parts of a butterfly martensite grow earlier than the layered re gions. A wing of a butterfly martensite grows like a group of lath mar tensites.