某发动机高压Ⅱ级涡轮盘封严篦齿裂纹分析

Cracks Analysis of Sealing Labyrinth on High-pressure Turbine Disc Ⅱ in an Aero-engine

某发动机高压Ⅱ级涡轮盘封严篦齿在试车后的分解检查中发现有裂纹显示。本文对裂纹分布、形貌及断口特征进行了观察,对封严篦齿的硬度和金相组织进行了检测,分析了裂纹性质和形成原因。结果表明,封严篦齿上的裂纹为热疲劳裂纹,裂纹的形成主要与第三封严篦齿附近的温度场有关。

After testing drive, an aero-engine was overhauled and some cracks were found on the sealing labyrinth of the high-pressure turbine disk Ⅱ. Observations were performed on the distributions and appearances of the cracks and the fracture surface morphology as well as the hardness and the metallographic characteristics of sealing labyrinth. The kind and the cause for such cracks were analyzed. The results show that the cracks on the sealing labyrinth are heat-fatigue cracked resulted by the temperature field around the third tooth of the sealing labyrinth.