Correlation of Cooling Rate, Microstructure and Hardness of S34MnV Steel
Abstract
A study of the hardenability, the microstructure and the phase transformations as a function of the cooling rate, of a marine crankshaft S34MnV steel has been performed using a Jominy end-quench test and dilatometry tests. The cooling rate has a distinct influence on the hardness and microstructure characteristics. As the cooling rate decreases, the hardness drops from HRC53 at the quenched end to HRC22 at the top end of the Jominy bar. The corresponding microstructures change from hard martensite to bainite, then soft pearlite and ferrite. The critical temperatures Ac1, 740 °C and Ac3, 830 °C were determined, and a continuous cooling transformation diagram was constructed from the dilatometric data. The important role of cooling rate on final hardness, phase transformation and microstructures are analyzed.
- Publication:
-
Metallurgical and Materials Transactions B
- Pub Date:
- August 2019
- DOI:
- 10.1007/s11663-019-01621-0
- Bibcode:
- 2019MMTB...50.1718C