热处理对Q390R钢微观组织及力学性能研究
Influence of Heat Treatment on Mechanical Properties and Microstructure of Q390RSteel
王军杰 1吴瑞萍 1武靖伟 2王天先 1吴昊 1张蕾 1李斌1
作者信息
- 1. 青岛兰石重型机械设备有限公司,青岛 266426
- 2. 中国科学院兰州化学物理研究所固体润滑国家重点实验室,兰州 730000
- 折叠
摘要
为研究Q390R钢在压力容器制造过程中的工艺适应性,通过对Q390R钢退火态、热成型(空冷)、热成型+正火(空冷)三种热处理状态下微观组织、力学性能、焊接冷裂纹敏感等方面进行研究.试验结果表明:Q390R钢在630℃ × 6hr退火、910℃ ×40min热成型+880℃ × 60min正火状态及原始态下的组织中均出现了沿轧制方向近似平行由铁素体和珠光体组成的带状组织,而在910℃ ×40min热成型下组织为等轴晶,带状组织几乎没有.三种热处理状态下力学性能均在516MPa-550MPa之间,各项力学性能、低温冲击韧性等均能满足工程技术条件要求.采用焊接热影响区最高硬度法试验,对Q390R钢进行了焊接冷裂纹敏感性测定,最终确定了最佳的焊前预热温度,试验结果表明,焊前采取适当的预热措施,可有效的降低Q390R钢的冷裂纹倾向.
Abstract
In order to study the process adaptability of Q390R steel in the manufacturing process of pressure vessel and provide basic data for the industrial application of the steel,this paper studies the microstructure and mechanical properties of Q390R steel under annealing state,hot forming(air cooling)and hot forming+normal ignition(air cooling).The test results show that Q390R steel exhibits a band like structure composed of ferrite and pearlite approximately parallel to the rolling direction in its microstructure after annealing at 630 ℃ × 6 hours,hot forming at 910 ℃ × 40 minutes,and normalizing at 880 ℃ × 60 minutes,as well as in its original state.However,under hot forming at 910 ℃ × 40 minutes,the microstructure is equiaxed with almost no band like structure.The tissue of Q390R steel plate is composed of ferrite and pearlite,and the ribbon tissue composed of ferrite and pearlite appears along the rolling direction after thermoforming+ignition(air cooling).The mechanical properties of the three heat treatment states are between 516 MPa and 550 MPa,and the mechanical properties and low-temperature impact toughness can meet the requirements of engineering technical conditions.The highest hardness test of welding thermal influence area measured Q390R steel with the sensitivity of welding cold crack method,and finally determined the best preheating temperature before welding.The test results show that appropriate preheating measures before welding can effectively reduce the cold crack tendency of Q390R steel.
关键词
Q390R钢/热处理规范/冷裂纹/力学性能/最高硬度法Key words
Q390R steel/heat treatment specification/cold crack sensitivity/mechanical properties引用本文复制引用
出版年
2024
NETL
NSTL
万方数据