Prediction and verification of CCT curves of A668 steel

doi:10.13251/j.issn.0254-6051.2020.10.029

Abstract

Abstract: In order to reduce the cost of drawing CCT curves and obtain more accurate calculation models of phase transformation to predict the properties and residual stress distribution of large components, the Li model was used to predict the CCT curves of A668 steel, and an enough and essential experimental group was developed based on the predicted results. After completing the phase transformation expansion experiment, the experimental results were used to correct the prediction model and the new model calculated the complete and accurate CCT curves. According to the expansion curves and metallographic results measured by DIL-805-ADT phase transformation dilatometer, the transformation type and transformation volume at different cooling rates were determined. The difference between the results which was calculated by original model and JMatPro software and the experimental results were compared. The process of modifying the prediction model and drawing the CCT curves was described. K-M equation for calculating martensite transformation was fitted. The relationship between different cooling rates and phase transformation was illustrated. A more accurate predictive model and complete CCT curves were obtained to guide actual production.

Key words: ASTM A668 steel, CCT curves, expansion curves

CLC Number:

TG142.1

Liu Xianqiang, Bu Hengyong, Li Qi, Li Mengnie. Prediction and verification of CCT curves of A668 steel[J]. Heat Treatment of Metals, 2020, 45(10): 148-153.

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