| 摘要: |
| 模拟Q390钢焊接工况,利用热膨胀法通过Gleeble1500热模拟机测定Q390钢的连续冷却转变曲线(CCT曲线).采用光学显微镜、扫描电镜对不同冷却速度下的试样进行显微组织观察及分析,通过对Q390钢连续冷却特性的分析和比较得出Q390钢的SH-CCT曲线.结果表明,SH-CCT曲线分为3个区域,高温区的铁素体+珠光体转变区,中温区内的贝氏体转变区,低温区的马氏体转变区.在0.015~0.1℃/s的冷却速度范围内获得铁素体+珠光体+粒状贝氏体的整合组织;在0.5~1℃/s冷却速度范围内有大量的粒状贝氏体组织生成;当冷却速度大于25℃/s时,有马氏体与残余奥氏体整合组织生成. |
| 关键词: Q390钢 热模拟 焊接CCT曲线 |
| DOI： |
| 分类号: |
| 基金项目:国防民口配套项目(115-4-1465) |
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| Measurement of Q390 steel welding CCT curve |
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ZHAO Yongtao1, DONG Junhui2, MA Yonglin1, ZHOU Junwei3
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1.Material and Metallurgy Engineering School, UST Inner Mongolia, Baotou 014010, China;2.Materials Science and Engineering, Inner Mongolia University of Science and Technology, Huhhot 010051, China;3.Steel-making Factory, Iron and Steel Group Company, Baotou 014010, China
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| Abstract: |
| By simulating Q390 steel welding condition, by means of thermal-dilatometer, continuous cooling transformation curve of Q390 steel was measured by Gleeble1500 thermal-simulator, at the same time, the microstructure of different cooling velocity was observed and analyzed by OM and SEM.SH-CCT curve was obtained through continuous cool character analysis and contrast.The results show that phase transformation region contains three parts:the ferrite and pearlite transition zone at high temperature, the bainite transition zone at moderate temperature and the martensite transition zone at low temperature.The microstructure including ferrite, pearlite and granular bainite can be obtained when the cooling velocity is between 0.015 and 0.1℃/s;lots of bainite structure can be obtained at 0.5-1℃/s cooling rate range;the martensite and residual austenite microstructure be obtained when the cooling velocity is beyond 25℃/s. |
| Key words: Q390 steel thermal-simulation SH-CCT |
