摘要
航空发动机风扇叶片产生了裂纹故障。通过对故障叶片进行外观检查、断口分析、叶尖端面检查、化学成分分析、硬度检测及金相组织分析,确定了风扇叶片裂纹的性质和产生原因。结果表明:风扇叶片裂纹为高周疲劳裂纹;钛合金风扇叶片与镍包石墨涂层摩擦相容性差,叶片与机匣镍包石墨涂层发生严重摩擦是导致叶片产生早期疲劳开裂的主要原因;同时,结构的应力集中以及振动应力也会引起疲劳裂纹的萌生及扩展;并提出了相应的改进建议,避免类似故障的发生。
The crack was occurred on the fan blade of aeroengine.Crack mode as well as failure reason were identified by the examination of failed blade appearance,analysis of fracture surface,inspection of blade tip,chemical composition analysis,hardness test and metallurgical structure analysis.Results indicated that the crack of fan blade was high cycle fatigue.Because of bad friction compatibility of NiC coating with titanium alloy fan blade,the serious friction between blade and NiC coating as a pivotal factor led to early fatigue fracture.Moreover,the fatigue crack was also influenced by stress concentration and vibration.Finally,the improved proposal was provided to avoiding analogous failure.
出处
《失效分析与预防》
2013年第2期112-116,共5页
Failure Analysis and Prevention
关键词
风扇叶片
裂纹
高周疲劳
摩擦
fan blade
crack
high-cycle fatigue
friction
