摘要
某航空发动机火焰筒整流罩在工作过程中发生断裂,通过宏/微观形貌观察、表面质量检查、金相检验、疲劳试验和动应力测试等方法分析了断裂原因。结果表明:整流罩断裂性质为高周疲劳断裂,疲劳裂纹源位于整流罩转角应力集中处;整流罩原始锻件晶粒尺寸粗大,使得疲劳强度较低,这是整流罩发生疲劳断裂的一个主要原因;在最大振动应力作用下,整流罩转角应力集中处载荷过大,明显高于其动强度储备,这是整流罩发生疲劳断裂的另一主要原因;整流罩转角应力集中处的异常轴向划痕进一步提高了此处的应力集中系数,促进了疲劳裂纹的萌生。
Fracture occurred in flame tube fairing of an aeroengine during working process. Fracture causes were analyzed by macro and micro morphology observation, surface quality inspection, metallographic inspection, fatigue test and dynamic stress test. The results show that the fracture mode of the fairing was high-cycle fatigue fracture, and the fatigue crack source was located at the corner stress concentration area of the fairing. Large grain size of original forging of the fairing decreased the fatigue strength, which was one of the main causes for fatigue fracture of the fairing. The load at the corner stress concentration area of the fairing was too large under the action of the maximum vibration stress, which was significantly higher than its dynamic strength reserve. This was another main reason for the fatigue fracture of the fairing. The abnormal axial scratches at the corner stress concentration area of the fairing further increased the stress concentration factor and promoted the initiation of fatigue cracks.
作者
刘欢
高建辉
迟庆新
门玉宾
佟文伟
李艳明
LIU Huan;GAO Jianhui;CHI Qingxin;MEN Yubin;TONG Wenwei;LI Yanming(AECC Shenyang Engine Research Institute,Shenyang 110015,China)
出处
《机械工程材料》
CAS
CSCD
北大核心
2022年第4期89-94,共6页
Materials For Mechanical Engineering
