Low-Temperature Bainite: A Thermal Stability Study

The thermal stability of nanobainitic structures obtained by heat treating two different high-carbon high-silicon steels at temperatures between 200 °C and 600 °C has been investigated by means of three complementary techniques, i.e., field emission gun-scanning electron microscopy, X-ray diffraction, and high-resolution dilatometry. Three main stages have been established, each of them characterized by a distinctive microstructure. Furthermore, the nanocrystalline structure generated by the bainite reaction confers the steel with an extraordinary tempering resistance.The authors gratefully acknowledge the support for this work by the Research Fund for Coal and Steel under the Contracts RFSR-CT-2014-00016 and RFSR-CT-2016-754070. The authors also acknowledge the supports of the following laboratories at CENIM, X ray diffraction, Metallography and Phase Transformations, and thank Dr. Irene Llorente and Mr. Javier Vara, and the rest of technical staff for their valuable help with the measurements.Peer Reviewe