摘要
采用DIL805A膨胀仪测定了09MnNiDR钢在不同冷却速率下连续冷却转变的膨胀曲线,结合金相-硬度法,绘制了该钢种的连续冷却转变曲线。结果表明:钢的临界相变点为Ac1=739℃,Ac3=890℃。冷却速率为0.1~2℃/s时,组织为铁素体+珠光体;冷却速率为3℃/s时,组织为粒状贝氏体;冷却速率超过10℃/s时开始生成板条状贝氏体;冷却速率达到30℃/s时,粒状贝氏体消失,开始生成马氏体,随着冷却速率的提高,马氏体含量升高;当冷却速率为50℃/s时,组织几乎全部转变为马氏体。为满足钢种组织为铁素体+珠光体的要求,需控制冷却速率低于2℃/s。
The dilatometric curves of 09MnNiDR steel were measured by DIL805A dilatometer.Combined with metallography and hardness measurements,continuous cooling transformation curves of the steel were plotted.The results show that the critical phase transition point of steel is Ac1=739℃and Ac3=890℃.With a cooling rate of 0.1~2℃/s,the microstructure is ferrite and pearlite.When the cooling rate is 3℃/s,the steel obtains granular bainite,and lath bainite is produced when the rate reaches 10℃/s.When the cooling rate reaches 30℃/s,granular bainite disappears while martensite begins to form.With increasing cooling rate,the martensite content continues to increase.When the cooling rate is at 50℃/s,the microstructure almost transforms into martensite.To meet the requirement that the microstructure of steel is composed of ferrite and pearlite,the cooling rate should be controlled below 2℃/s.
作者
丁航
王丽君
杨勇
巨银军
周国治
DING Hang;WANG Lijun;YANG Yong;JU Yinjun;CHOU Kuochih(University of Science and Technology Beijing,Collaborative Innovation Center of Steel Technology,Beijing 100083,China;University of Science and Technology Beijing,State Key Laboratory of Advanced Metallurgy,Beijing 100083,China;Hunan Valin Xiangtan Iron and Steel Co.,Ltd.,Xiangtan 411100,Hunan,China)
出处
《江西冶金》
2022年第3期1-6,共6页
Jiangxi Metallurgy
基金
国家自然科学基金资助项目(51922003)
中央高校基本科研业务费资助项目(FRF-TP-19-004C1)。
