Morphology and formation of three-phase pearlite in an aged 100Mn13 steel

Abstract

The pearlite formed in 100Mn13 high carbon high manganese steel after 1323 K water toughening subsequently 923 K aging treatment is studied by transmission electron microscope and high-resolution technique. The results show that the pearlite is composed of three phases, which are M₃C lamellae, M₇C₃ lamellae, and ferrite lamellae, respectively, with the orientation relationships of ( $01\overline{1}$ )_α∥( $2\overline{2}\overline{1}$ )_M7C3, ( $\overline{1}01$ )_α∥( $10\overline{2}$ )_M3C, ( $2\overline{1}1$ )_M3C∥( $2\overline{1}\overline{3}$ )_M7C3, [ $251$ ]_M3C∥[ $542$ ]_M7C3∥[ $111$ ]_α. And M₇C₃ is formed at the phase interface between M₃C and α. The growth physical model of three-phase pearlite is proposed.