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Effect of Isothermal Temperature on Growth Behavior of Nanostructured Bainite in Laser Cladded Coatings.

ABSTRACT: The growth and propagation behavior of austenite-to-bainite isothermal transformation in laser-cladded, Si-rich, and Fe-based coatings is investigated. The crystallographic features, orientation relationship at different isothermal temperatures, and the morphology of the nanostructured bainite are determined. The Nishiyama-Wassermann type orientation relationship is observed at a high temperature and at a low temperature, and mixed Nishiyama-Wassermann and Kurdjumov-Sach mechanisms are seen. The growth direction is investigated by the partial dislocation theory and an extrapolated model based on the repeated formation of lenticular-shaped subunits and pile-up along the close-packed directions of the close-packed planes. The variants of the bainite growth directions would be more selective at the high transformation temperature.

SUBMITTER: Guo Y

PROVIDER: S-EPMC5551843 | BioStudies | 2017-01-01

SECONDARY ACCESSION(S): 10.3390/ma10070800

REPOSITORIES: biostudies

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