Effects of austenite deformation on continuous cooling transformation of the pearlite heat-resistant steel

ABSTRACT

Continuous cooling transformation (CCT) diagrams of undeformed and 40% compressively deformed pearlite heat-resistant steels at 950°C were obtained by a combined method of dilatometry and metallography. The microstructure and hardness of the steel under these two experimental conditions were compared and analysed. The effects of austenite deformation on the CCT of pearlite heat-resistant steel are discussed. The CCT diagrams show that the austenite deformation extends the ferrite and pearlite transformation fields and increases the critical cooling rates to achieve the ferrite and pearlite microstructure, which causes the CCT curve to shift to the left. However, austenite deformation suppresses the transformation of bainite and martensite. Moreover, it reduces the hardness of the tested steel at the same cooling rate and grain size of the ferrite at low cooling rates.

KEYWORDS:

• Pearlite heat-resistant steel
• austenite deformation
• continuous cooling transformation
• microstructure
• phase transformation
• critical cooling rate
• CCT diagram
• hardness

Disclosure statement

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

Additional information

Funding

The authors gratefully acknowledge the financial support of this research by National Science Foundation of China [grant number 51874028].