高温合金涡轮转子叶片裂纹形成机理  

Mechanism of Cracks in the Blades of High Temperature Alloy Turbo Rotor

作　　者：王影[1] 王宇宁 刘春立[1] 韩露[1] 卢鹉[1] WANG Ying;WANG Yuning;LIU Chunli;HAN Lu LU(Aerospace Research Institute of Materials&Processing Technology,Beijing 100076)

机构地区：[1]航天材料及工艺研究所,北京100076

出　　处：《宇航材料工艺》2021年第6期89-93,共5页Aerospace Materials & Technology

摘　　要：高温合金涡轮转子在经历过多次发动机试车后荧光检查发现叶片根部存在裂纹,对涡轮转子叶片裂纹进行分析。结果表明,涡轮转子叶片裂纹位于叶片根部进出口薄壁区,裂纹的开裂模式为高温疲劳开裂,属于低周疲劳,为寿命型失效。试车过程中转子叶片根部应力集中部位在高温及交变应力的交互作用下,叶尖根部应力集中区域发生蠕变和晶界择优氧化,高温蠕变和沿晶氧化相互促进,导致叶片根部的晶界弱化开裂,形成了疲劳源区,进而在后续工作过程中发生高温疲劳扩展。Cracks in the blades’ root of turbo rotor made from high temperature alloy were detected by fluorescence examination after several engine trial runs. The results indicate that the cracks are located in the thinwalled area in the blade,and the cracking mode is high temperature fatigue cracking,which can be classified into low-cycle fatigue and life-relevant failure. In the trail run process,the stress concentration location is exposed to the effect of high temperature and alternating stress. Therefore,selective oxidation in the grain boundaries happen and oxide products grow in a wedge-like shape along the grain boundaries. By the mutual influence of both high temperature oxidation and alternating stress,the stress concentration location in the blades’ root also experiences creep and slippage. With the effect of creeping damage and intergranular oxidation,the weakened grain boundaries start to crack and cracks expand along the grain boundaries,forming the fatigueorigin. At last,high temperature fatigue cracks further expand in the subsequent process.

关 键 词：高温合金 涡轮转子 裂纹 高温疲劳 沿晶氧化 

分 类 号：V231[航空宇航科学与技术—航空宇航推进理论与工程]