Abstract
The phase transformation in steel during friction stir welding (FSW) was studied using the Fe–24wt%Ni–0.1%C alloy. When the FSW condition was adapted in order that the maximum temperature was sufficiently reached for austenitization, the volume fraction of the retained austenite in the stir zones was significantly increased. A crystallographic measurement revealed that the martensite transformation was inhibited after the stirring during which the austenite was plastically deformed. Additional experiments clarified that the dislocation and grain boundary introduced by the plastic deformation of austenite may provide a barrier against the martensite transformation. The stabilized austenite enhances the work hardening rate and maximum strength at room temperature due to the transformation induced plasticity (TRIP).
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Miura, T., Ueji, R., Fujii, H. (2015). Stabilization of the Retained Austenite in Steel by Friction Stir Welding. In: Mishra, R.S., Mahoney, M.W., Sato, Y., Hovanski, Y. (eds) Friction Stir Welding and Processing VIII. Springer, Cham. https://doi.org/10.1007/978-3-319-48173-9_5
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DOI: https://doi.org/10.1007/978-3-319-48173-9_5
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-48604-8
Online ISBN: 978-3-319-48173-9
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