J. Phys. IV France
Volume 05, Numéro C8, Décembre 1995
International Conference on Martensitic Transformations – ICOMAT 95
Page(s) C8-351 - C8-354
International Conference on Martensitic Transformations

J. Phys. IV France 05 (1995) C8-351-C8-354

DOI: 10.1051/jp4:1995851

Carbon Diffusion and Kinetics During the Lath Martensite Formation

T.Y. Hsu (Xu Zuyao)

Shanghai Jiao Tong University, Dept. Materials Science, Shanghai, 200030, China

Calculations verify that carbon diffusion may occur during the lath martensite formation. Accordingly, the diffusion of interstitial atoms or ions must be taken into account when martensitic transformation is defined as a diffusionless transformation. In derivation of the kinetics equation of the athermal martensitic transfomation, regarding the carbon diffusion, i .e. the enrichment of the austenite during the lath martensite formation, and ΔG(γ→α) being function of the temperature and the carbon content in austenite, the kinetics equation is modified to a general form as : [MATH]
where Co and Cs are carbon contents in the austenite before and after quenching respectively. Consequently, the alloying element not only influences Ms, but also the diffusibility of carbon and both factors govern the amount of retained austenite in quenched steel which dominates in determing the toughness of the steel.

© EDP Sciences 1995