淬火温度对12Cr12Mo钢的组织、力学性能及低周疲劳性能的影响
Effect of quenching temperature on microstructure,mechanical properties and low-cycle fatigue performance of 12Cr12Mo steel
刘俊建 1袁周亮 2王万里 1邵敏 2占先强 1汤文明2
作者信息
- 1. 大唐锅炉压力容器检验中心有限公司,安徽 合肥 230088;中国大唐集团科学技术研究总院有限公司华东电力试验研究院,安徽 合肥 230088
- 2. 合肥工业大学材料科学与工程学院,安徽 合肥 230009
- 折叠
摘要
采用光学显微镜、扫描电镜、X射线衍射仪、布氏硬度计和电子万能试验机等研究了汽轮机叶片用12Cr12Mo钢经不同温度淬火及680℃回火处理后的显微组织及力学性能;并研究了其经不同工艺处理后的低周疲劳性能,建立了寿命预测模型.结果表明:随着淬火温度(940～1000 ℃)的升高,12Cr12Mo钢的奥氏体晶粒持续长大,马氏体板条宽度逐渐增大,更多的碳化物颗粒固溶于基体中,力学性能呈现先上升后下降的趋势;980 ℃淬火及680 ℃回火后12Cr12Mo钢的显微组织最好,进而其力学性能最佳、循环断裂次数最大、棘轮应变最小和低周疲劳性能最好;1000℃淬火及680 ℃回火后12Cr12Mo钢中含较多的δ-铁素体,导致其力学性能较差;当应力比R=0.1时,12Cr12M o钢的低周疲劳寿命预测模型为:SeqN00134=495.5072.
Abstract
Microstructure and mechanical properties of 12Cr12Mo steel for steam turbine blades after quenching at different temperatures and tempering at 680 ℃ were studied using optical microscope,scanning electron microscopy,X-ray diffraction,Brinell hardness tester and electronic universal testing machine.The low-cycle fatigue performance of the 12Cr12Mo steel after heat treatment by different processes was studied,and its life prediction model was established.The results show that with the increase of quenching temperature(940-1000 ℃),the austenite grain of the 12Cr12Mo steel continues to grow,the width of martensite lath gradually increases,more carbide particles are dissolved in the matrix,and the mechanical properties show a trend of first increasing and then decreasing.The microstructure of the 12Cr12Mo steel after quenching at 980 ℃ and tempering at 680 ℃ is the best,resulting in the best mechanical properties,maximum number of cyclic fractures,minimum ratcheting strain,and best low-cycle fatigue performance.After quenching at 1000 ℃ and tempering at 680 ℃,the 12Cr12Mo steel contains more amount of δ-ferrite leads to poor mechanical properties.When the stress ratio R=0.1,the low-cycle fatigue life prediction model for the 12Cr12Mo steel is:SeqN0.0134f=495.5072.
关键词
12Cr12Mo钢/热处理/显微组织/力学性能/低周疲劳/寿命预测模型Key words
12Cr12Mo steel/heat treatment/microstructure/mechanical property/low-cycle fatigue/life prediction model引用本文复制引用
出版年
2024
NETL
NSTL
万方数据