摘要
采用光学显微镜和万能拉伸试验机等研究了轧制过程中的开冷温度和终冷温度对Q550D钢板的显微组织、铁素体和M/A岛占比以及室温拉伸性能的影响。结果表明,不同开冷温度和终冷温度下,试样中M/A岛的形态主要为颗粒状、块状和断续分布的长条状,且M/A岛主要分布在贝氏体或者铁素体的相界处;试样中M/A岛体积分数会随着开冷温度或终冷温度的降低而不断增加,铁素体含量会随着开冷温度和终冷温度的降低而分别呈现逐渐增加和略有减小的特征;在相同终冷温度下,降低开冷温度对试样抗拉强度的影响不大,而屈服强度和屈强比减小;相同开冷温度下,终冷温度的减小会使得屈服强度和屈强比增大;当开冷温度为755℃、终冷温度为395℃时,试样具有最佳的综合性能,此时抗拉强度和屈服强度分别为781和640 MPa、屈强比为0.82,满足590 MPa级抗震钢板的技术要求。
The influences of initial cooling temperature and final cooling temperature on microstructure,ferrite,M/A island proportion and tensile properties at room temperature of Q550 D steel plate were studied by optical microscope and universal tensile testing machine.The results show that under different initial cooling temperatures and final cooling temperatures,the shapes of M/A islands in the sample are mainly granular,massive and intermittently distributed strips,and the M/A islands are mainly distributed at the boundary of bainite or ferrite.The volume fraction of M/A islands in the sample increases with the decreasing of the initial cooling temperature or the final cooling temperature,and the ferrite content increases gradually with the decreasing of the initial cooling temperature and decreases slightly with the decreasing of the final cooling temperature.Under the same final cooling temperature,the influence of reducing the initial cooling temperature on the tensile strength of sample is not significant,but the yield strength and yield strength ratio decrease.Under the same initial cooling temperature,the reduction of the final cooling temperature increases the yield strength and yield strength ratio.When the initial cooling temperature is 755℃and the final cooling temperature is 395℃,the sample has the best comprehensive performance,the tensile strength and yield strength are 781 and 640 MPa respectively,and the yield strength ratio is 0.82,which meets the technical requirements of anti-seismic steel plate with 590 MPa grade.
作者
赵夏清
邢炜
卢凤奇
沈功福
Zhao Xiaqing;Xing Wei;Lu Fengqi;Shen Gongfu(School of Construction Engineering,Shanxi Vocational and Technical College,Xi’an 710038,China;School of Materials Science and Engineering,Xi’an Jiaotong University,Xi'an 710049,China)
出处
《锻压技术》
CAS
CSCD
北大核心
2021年第1期186-190,共5页
Forging & Stamping Technology
基金
陕西省科技攻关资助项目(2018KD8-G16)。
关键词
Q550D钢板
开冷温度
终冷温度
组织
力学性能
Q550D steel plate
initial cooling temperature
final cooling temperature
microstructure
mechanical properties
