Continuous cooling transformation of high aluminum TRIP steel and effect of hot deformation on its phase transformation

doi:10.13251/j.issn.0254-6051.2020.06.019

Abstract

Abstract: Continuous cooling transformation curves, transformation law and the effect of hot deformation on transformation of a high aluminum TRIP steel were studied by means of thermal dilation test and hot-compressing thermal simulation test. In addition, the driving force of transformation was qualitatively analyzed. The results show that the CCT curves can be divided into three regions. With the cooling rate increasing, the volume fractions of ferrite and pearlite decrease, the volume fractions of bainite and martensite increase, respectively. The shape of bainite transforms from granular to feather-like or lath-like. As a result of dynamic recrystallization caused by hot deformation, the original austenite grain of the samples is refined and acicular ferrite is observed at high cooling rates. Hot deformation can provide more nucleation sites and higher driving force of γ→α transformation, thus resulting in a shorter bainite transformation incubation period and a finer the room temperature microstructure.

Key words: high aluminum TRIP steel, CCT curves, hot deformation, microstructure, driving force

CLC Number:

TG142

Huang Huiqiang, Di Hongshuang, Gong Dianyao. Continuous cooling transformation of high aluminum TRIP steel and effect of hot deformation on its phase transformation[J]. Heat Treatment of Metals, 2020, 45(6): 84-88.

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