Formation Mechanism 上游充通大学 SHANGHAI JIAO TONG UNIVERSITY Transformation temperature:(>Ac1) Phases: a + Fe3C Y Compositions (wt%):0.02% 6.7% 0.77% Crystal structures: BCC Orthorhombic FCC The austenitization involves crystal structure change,dissolution of cementite,and the diffusion of C. JIAO TONG UNIV 食 K.Chen 11K. Chen Formation Mechanism 11 Transformation temperature: (> Ac1) The austenitization involves crystal structure change, dissolution of cementite, and the diffusion of C. Phases： α + Fe3C → γ Compositions (wt%)：0.02% 6.7% 0.77% Crystal structures： BCC Orthorhombic FCC