Producing Nanobainite on Carburized Surface of a Low-Carbon Low-Alloy Steel

Avishan B., Talebi P., TEKELİ S., Yazdani S.

JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE, vol.32, no.1, pp.211-220, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 32 Issue: 1
  • Publication Date: 2023
  • Doi Number: 10.1007/s11665-022-07096-6
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Aerospace Database, Applied Science & Technology Source, Aquatic Science & Fisheries Abstracts (ASFA), Chemical Abstracts Core, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.211-220
  • Keywords: carburizing, electron microscopy, heat treatment, nanostructured Bainite, optical microscopy, steel, x-ray diffraction, MECHANICAL-PROPERTIES, BAINITIC STEELS, WEAR-RESISTANCE, ATOM-PROBE, BEHAVIOR, MICROSTRUCTURE, AUSTENITE
  • Gazi University Affiliated: Yes


Conducting the carburizing process on the surface layer of low-carbon steel and subsequent austempering heat treatment can be implemented to obtain nanobainite microstructure on the surface of steels. In this research, steel with 0.23 wt.% carbon was carburized for 3 h at 900 degrees C in a liquid salt bath containing sodium cyanide, sodium carbonate, and sodium chloride and immediately quenched to room temperature. The samples were then heated to 900 degrees C for 30 min and isothermally transformed at three different temperatures of 200, 250 and 300 degrees C for 72, 24 and 12 h, respectively. It was found that nanostructured bainite was formed on the surface layer and the subunits of bainitic ferrite and high-carbon austenite films were almost 60-300 nm thick depending on the heat treatment temperature. It was also found that the samples austempered at these temperatures contained 18, 21 and 28% volume fractions of retained austenite on the surfaces, respectively. Due to the comparable microstructural characteristics, similar friction coefficients were obtained as for ordinary nanostructured bulk bainitic steels with high-carbon content.