某型航空发动机散热器支架断裂失效分析

摘要

通过对某型航空发动机故障散热器支架进行外观检查、断口分析、表面微观检查、截面金相检查以及材质分析,确定了故障散热器支架断口的高周疲劳属性,明确了表面电加工重熔层中存在的微裂纹、尖锐棱角和结构设计不足造成了应力集中。结果表明：应力集中导致该支架过早发生疲劳断裂,振动载荷也加速了该支架疲劳断裂故障的发生;最后提出了相应的改进建议。%The high cycle fatigue property was defined by the visual inspection and fracture analysis,surface-microscopic inspection,cross-section metallographic inspection and material analysis of an aeroengine failured radiator support.The stress concentration was caused by the microcracks,sharp angular and structure design weakness in the EDM surface remelted layer.The results show that stress concentration is the key factor that lead to fatigue fractures early,the vibration loadings is another factor that result in the fatigue facture.Finally,the improvement advice was correspondingly proposed.