TRANSMISSION ELECTRON-MICROSCOPIC STUDY ON INSITU CARBIDE REACTIONS DURING TEMPERING OF HIGH CARBON HIGH CHROMIUM STEELS RAPIDLY QUENCHED FROM MELTS

The carbide reactions of M//3C yields M//7C//3 yields M//2//3C//6 were examined by electron microscopy using two kinds of high carbon-high chromium steels quenched rapidly from the melts. In tempered 16. 5%Cr-3. 65%C steel, M//7C//3 carbide was observed to nucleate on the cementite/ferrite interface and grow at the expense of cementite. this indicates that the transformation from cementite to M//7C//3 occurs by the in situ mechanism.