The dynamic precipitation of ferrite during austenite deformation above the Ae3 temperature, was first reported by Yada et al. in the 1980s. These observations were later confirmed for a wide range of steel compositions and processing conditions. The aim of this work is to clarify the mechanism by which ferrite formation takes place above the Ae3 temperature. To that end, a simple model for ferrite growth as a result of the movement of disconnections under applied stress is established. This motion, opposed by the back stress, increases the Gibbs energy as a result of deformation of ferrite above Ae3. Preliminary calculation suggests that the dynamic transformation is possible near the Ae3 temperature for large stress. The results are discussed in terms of experiments using a deformation dilatometer. / Thesis / Master of Applied Science (MASc)

京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第23437号 / エネ博第424号 / 新制||エネ||81(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻 / (主査)教授 森井 孝, 教授 佐川 尚, 教授 片平 正人 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM