THEORETICAL PREDICTION OF PROEUTECTOID FERRITICTRANSFORMATION IN HYPO-PROEUTECTOID STRUCTRAL STEELS

查看全文 作　　者：H.B.Chang;Z.G.Li;T.Y.Hsu;Z.Y.Xu;X.Y.Ruan 出　　处：《Acta Metallurgica Sinica(English Letters)》索引1998年第11卷第3期,共8页 摘　　要：Proeutectoid ferrite with carbon content xo precipitating from austenite in a multicomponent steel at temperature T is supposed to be equivalent to proeutectoid ferrite with the same carbon content precipitating from austenite in Fe-C binary system at temperature T’.is described as the temperature difference of proeutectiod ferrite formation, and can be calculated from the Fe-X diagrams and the equilibrium temperature A3. By introducing Tf and basing on the thermodynamic model for Fe-C binary alloy, the driving force for phase transformation from austenite to proeutectoid ferrite in multicomponent steels has been successfully calculated. Through the Johnson-Mehl equation and using the data hem known TTT diagrams, the relationship between the chemical composition and the intedecial edenly packeter as well as activation energy for proeutectoid ferrite formation can be calculated. The starting curves of proeutectoid ferritic transformation calculated in this way in some hypo-proeutectoid structural steels agree well with the erperimental data. 关 键 词：proeutectoid FERRITE formation temperature DIFFERENCE INTERFACIAL enerpy parameters ACTIVATION energy for DIFFUSION Johnson-Mehl equation