摘要
采用金相显微镜、扫描电子显微镜、室温拉伸试验、低温冲击试验等方法与手段研究了不同温度回火处理对Q690高强钢显微组织与力学性能的影响。结果表明:淬火态Q690钢的组织为铁素体、板条状马氏体、贝氏体组成。随着回火温度的升高,Q690钢组织中板条特征越来越不明显。460℃回火的Q690钢的组织为回火托氏体和回火贝氏体。500℃回火的Q690钢组织发生明显回复,析出碳化物增多。460℃回火的Q690钢的综合力学性能最佳,其屈服强度为737.4 MPa,抗拉强度为875.6 MPa,伸长率为14.1%,屈强比为0.84,-40℃低温冲击吸收能量为124 J,各项力学性能指标均达到GB/T 19879—2015标准要求。
The effects of tempering treatment at different temperatures on the microstructure and mechanical properties of Q690 high strength steel were studied by means of metallographic microscope, scanning electron microscope, room temperature tensile test and low temperature impact test. The results show that the microstructure of quenched Q690 steel is composed of ferrite, lard martensite and bainite. With the increase of tempering temperature, the strip characteristics in the microstructure of Q690 steel become less and less obvious. The microstructure of Q690 steel tempered at 460 ℃ is tempered tortenite and tempered bainite. And the microstructure of Q690 steel tempered at 500 ℃ recovers obviously and the carbide precipitates increase. The comprehensive mechanical properties of Q690 steel tempered at 460 ℃ are the best, with yield strength of 737.4 MPa, tensile strength of 875.6 MPa, elongation of 14.1%, yield strength ratio of 0.84, and impact absorption energy of 124 J at -40 ℃. All the mechanical properties meet the requirements of GB/T 19879—2015.
作者
徐志斌
宋贤萍
刘阳
殷文峰
XU Zhibin;SONG Xianping;LIU Yang;YIN Wenfeng(Luohe Institute of Technology,Henan University of Technology,Luohe 462002,China;Henan Province Engineering Research Center of Intelligent Green Construction,Zhengzhou 450046,China;School of Materials Science and Engineering,Zhengzhou University,Zhengzhou 450001,China)
出处
《热加工工艺》
北大核心
2022年第24期156-160,共5页
Hot Working Technology
基金
河南省重点研发与推广专项(科技攻关)资助项目(212102310959)。
关键词
Q690钢
回火温度
显微组织
力学性能
Q690 steel
tempering temperature
microstructure
mechanical properties
