发动机涡轮叶片榫头荧光显示分析  

Analysis on Fluorescent Indication of High-pressure Turbine Blade Dovetails in an Aero-Engine

作　　者：孙铁峰[1] 刘建平[1] 李明[1] 杨树林[1] 

机构地区：[1]中国人民解放军驻沈阳黎明航空发动机制造公司军事代表室,沈阳110043

出　　处：《失效分析与预防》2009年第2期118-121,共4页Failure Analysis and Prevention

摘　　要：发动机涡轮叶片在成品检验和工厂试车后检验时,发现大量叶片榫头存在聚集性点状显示。采用扫描电镜观察和金相分析,研究了荧光显示部位缺陷的性质及其产生的原因。结果表明荧光显示部位存在明显的显微疏松,榫头处有清晰的磨削痕迹,局部有微裂纹。显微疏松在磨削应力作用下局部撕裂,磨削痕迹使显微疏松连接成片,从而导致聚集性荧光显示。热处理和工厂试车时的高温促使缺陷暴露,使得易于在该阶段发现缺陷。建议适当降低拉晶速度,延长拉晶时间,可以显著减轻显微疏松的程度。改进工艺的叶片腐蚀后未发现明显的显微疏松。The dovetails of the high-pressure turbine blades in an acre-engine show assembling fluorescent indication during the final product inspection and especially during the examination after trial run tests, The characteristic and cause of the defects in- dicated by fluorescence were studied by optical microscopy and scanning electron microscopy （SEM）. The resuhs show that there was obvious microporosity at the positions indicated by fluorescence, and clear grinding traces and some local mierocracks were found at the dovetails. Microporosity was torn into microcracks under the effect of the grinding stress and inclined to assemble because of the grinding traces, which resulted in the assembling fluorescent indication. The high temperature during heat treatment and trial run tests can promote the exposure of the defects, so the defects can easily be detected by fluorescence inspection during these periods. Microporosity and fluorescent indication can be alleviated by decreasing the pulling rate and prolonging the pulling time. No obvious microporosity was detected at the bottom surface of the dovetail after improving the production process.

关 键 词：荧光显示 显微疏松 叶片 DZ22合金 

分 类 号：V232.4[航空宇航科学与技术—航空宇航推进理论与工程]