摘要
采用疲劳试验、内耗试验和透射电镜观察等研究了应变时效处理对P91马氏体钢在550℃高温低周疲劳行为的影响。结果表明:碳原子形成的Cottrell气团在位错处偏析并对其有效钉扎是P91钢产生应变时效的主要原因;应变时效试样在高温低周疲劳时出现的显著包辛格(Bauschinger)效应降低了它的疲劳寿命;包辛格效应主要机制是应变时效导致林位错密度增大,在循环载荷下,形成了稳定的胞状结构。
The effect of strain ageing treatment on the low cycle fatigue(LCF)behavior of P91 martensitic steel at 550 ℃ was investigated by means of fatigue testing,internal friction testing and transmission electron microscopy.The results show that the main reasons that P91 steel happened strain ageing were precipitation of Cottrell air mass made of carbon atoms near dislocations and pinning them.Strain ageing specimen happened remarkable Bauschinger effect under LCF,which reduced the LCF life at high temperature.The increase of tree dislocation density due to strain ageing,which led to form stable cellular structure under cyclic loading,was mainly responsible for Bauschinger effect.
出处
《机械工程材料》
CAS
CSCD
北大核心
2014年第10期37-41,共5页
Materials For Mechanical Engineering
基金
国家高科技研究发展(863)计划项目(2009AA044802)
安徽工业大学青年教师科研基金资助项目(2013021)
关键词
P91钢
包辛格效应
内耗
应变时效
低周疲劳
P91 steel
Bauschinger effect
internal friction
strain ageing
low cycle fatigue
