Austenite grain growth of medium-carbon alloy steel with aluminum additions during heating process
来源期刊：International Journal of Minerals Metallurgy and Materials2019年第3期
论文作者：Zi-yi Liu Yan-ping Bao Min Wang Xin Li Fan-zheng Zeng
文章页码：282 - 290
摘 要：In this study, the effects of heating temperature（850–1100°C） and holding time（30–150 min） on the grain growth behavior of austenite in medium-carbon alloy steel were investigated by conducting experiments. The abnormal grain growth and mixed grain structure phenomenon are explained using an equilibrium precipitation phase diagram calculated by Thermo-Calc software package. The Al N particles were observed by field-emission scanning electron microscopy（FESEM）, and the amount of AlN precipitations was detected by electron probe microanalysis（EPMA）. Based on the research results, it was found that the average grain size of austenite in the test steel increased continuously with the increase of temperature and holding time. Furthermore, the abnormal growth of austenite occurred in the test steel at 950°C, and the heating temperature affected the austenite grain size more significantly. In addition, the decline in the amount of AlN second-phase particle in the test steel, which weakened the "pinning" effect on austenite grain boundaries, resulted in abnormal growth and the development of mixed austenite grain structures. The prediction model for describing the austenite grain growth of medium-carbon alloy steel during heating was established by regression analysis of the experimental data, and the model was verified to be highly accurate.
Zi-yi Liu1，Yan-ping Bao1，Min Wang1，Xin Li1，Fan-zheng Zeng2
1. State key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing2. Xiangtan Iron & Steel Co., Ltd.of Hunan Valin
摘 要：In this study, the effects of heating temperature（850–1100°C） and holding time（30–150 min） on the grain growth behavior of austenite in medium-carbon alloy steel were investigated by conducting experiments. The abnormal grain growth and mixed grain structure phenomenon are explained using an equilibrium precipitation phase diagram calculated by Thermo-Calc software package. The Al N particles were observed by field-emission scanning electron microscopy（FESEM）, and the amount of AlN precipitations was detected by electron probe microanalysis（EPMA）. Based on the research results, it was found that the average grain size of austenite in the test steel increased continuously with the increase of temperature and holding time. Furthermore, the abnormal growth of austenite occurred in the test steel at 950°C, and the heating temperature affected the austenite grain size more significantly. In addition, the decline in the amount of AlN second-phase particle in the test steel, which weakened the "pinning" effect on austenite grain boundaries, resulted in abnormal growth and the development of mixed austenite grain structures. The prediction model for describing the austenite grain growth of medium-carbon alloy steel during heating was established by regression analysis of the experimental data, and the model was verified to be highly accurate.
关键词：
