Application of ultrafast heating and tempering to plate steel

Abstract

The microstructure and tensile properties were studied in a low-alloy steel plate treated under ultra-fast heating, quenching, and tempering. The microstructure after heat-treatments was predominantly martensite, with low fraction of bainite and ferrite. The tensile tests showed a 100 MPa improvement in strength and a doubling of the total elongation with the increase in heating rate. The tempering process considerably enhanced the ductility from 1–4% to up to 14% in the samples treated at fast heating rates..Furthermore, the work hardening capacity of ultra-fast heated steel was superior compared to steel treated under conventional quenching and tempering. The results suggest that the tempering stage after ultra-fast heat-treatments and quenching further improves the properties compared to the standard quenched and tempered condition.

KEYWORDS:

• Steel
• microstructure
• parent austenite grain size
• mechanical properties
• ultra-fast heating
• tempering

Acknowledgements

E.I. Hernández Durán gratefully acknowledges the support of the National Research and Development Agency of Chile (ANID) ANID/Doctorado Nacional/2017-21171. F.M. Castro Cerda acknowledges the financial support of Dicyt-Usach, project no. 052114CC.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

E.I. Hernández Durán gratefully acknowledges the support of the Agencia Nacional de Investigación y Desarrollo de Chile (ANID) [ANID/Doctorado Nacional/2017-21171]. F.M. Castro Cerda acknowledges the financial support of internal funding of the University of Santiago de Chile DICYT), project no. 052114CC.