The macro-structure, micro-morphology and micro-structure were detected by optical microscope, scanning electrical microscope and electrical probe micro-analyzer. The temperature range on different areas of turbine blade was deduced during. And-the reason that caused blade fractured was discussed. The results show that,during the starting stage of engine, γ'phase dissolved or even turn out to be incipient melting caused by over-heat, liquefaction was found in parts of interdendritic and grain boundary, leading edge and trailing edge of blade overburned seriously where the temperature reached more than 1260℃ , temperature of central area on the blade was around 1220℃ where away from leading edge about 6mm, temperature of area was under 1180℃ in short time where away from leading edge about 8mm. Overload state on blade caused by over-heat, and finally some of blade fractured instantly.%运用光学显微镜、扫描电子显微镜、电子探针微束分析仪对断裂叶片表面进行了宏观形貌、叶片断口宏观、微观形貌及显微组织分析,推断出叶片使用时不同部位所承受的温度范围,并对断裂原因进行了探讨.结果表明:启动超温致使叶片γ′相回溶甚至过烧至初熔状态,局部枝晶间和晶界出现明显液化现象,叶片前缘和后缘过烧程度严重,该区承受的温度达到甚至超过了1260℃,距叶片前缘约6mm中心区,其承温在1220℃左右,离叶片前缘8mm处,其短时承温在1180℃以下；超温使叶片处于严重过载状态,最终造成多个叶片瞬间断裂.
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