Phase transition characteristics of M_2C eutectic carbide in M2 high speed steel

Effects of different heating temperature and holding time on the decomposition behavior of M2C eutectic carbide in M2 high speed steel were investigated by SEM and EDS.The results show that the degree of decomposition of M2C eutectic carbide is increased with the increase of heating temperature and holding time,but the heating temperature plays a main role.The process of decomposition of M2C eutectic carbide was discussed.The characteristics of decomposition are that the decomposition of M2C eutectic carbide is controlled by the diffusion behavior of atoms;the M6C carbides form in the outer layer of the original M2C eutectic carbide and the MC carbides form in the inner layer.