摘要
采用化学成分分析、硬度测试、断口形貌观察以及金相检验对某炼油厂烟气轮机叶片断裂原因进行了分析。结果表明:叶片断裂性质为早期疲劳断裂,失效原因是锻造工艺不当;断裂起源于叶片排气边晶界处;叶片材料晶粒粗大并有大量的混晶存在以及沿晶界析出的链状连续碳化物,降低了叶片材料的强度和韧性,促进了裂纹萌生与扩展,导致叶片在交变应力的作用下疲劳断裂。
The fracture of flue gas turbine blade of a refinery was analyzed by means of chemical composition analysis, hardness test, fracture surface observation and metallographic examination. The results show that the fracture feature of the blade was early fatigue fracture, and the failure was caused by improper forging process. Fatigue cracks originated from the grain boundaries at the exhaust edge of the blade. Coarse grains and a large number of grain stripes as well as chain carbides along the grain boundaries decreased the blade material strength and toughness, and accelerated the crack initiation and propagation that resulted in the fracture of the turbine blade under alternating stress.
出处
《机械工程材料》
CAS
CSCD
北大核心
2010年第10期79-81,共3页
Materials For Mechanical Engineering
基金
山东省科学院博士基金资助项目(2007-09)
关键词
烟气轮机
叶片
疲劳
沿晶断裂
flue gas turbine
blade
fatigue
intergranular fracture
