摘要
GH4169合金是航空发动机热端部件的重要选材,该合金的高温蠕变和疲劳性能是决定发动机安全性与可靠性的关键因素。本文利用岛津疲劳试验机研究了GH4169合金在455℃的高温疲劳行为,观察了合金疲劳裂纹萌生、扩展过程,考察了晶粒度和疲劳寿命的关系。
GH4169 alloy has excellent mechanical properties at high temperature and good process abihty,therefore it has been widely used in aero engine turbine disk,compressor disk,power turbine shaft(rotating components).The operational life of rotating components is determined by the high temperature mechanical properties of GH4169 alloy,especially creep and fatigue properties.In this paper,high temperature fatigue behavior at 455℃ of GH4169 alloy is discussed.Fatigue crack initiation and propagation process is in-situ observed,relationship of grain size and fatigue life is investigated.
引文
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