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在500℃和600℃两个温度条件下,研究了第二代粉末高温合金FGH96的缺口疲劳性能,将原始数据的曲线拟合成S-N曲线,分析光滑与缺口试样的Kf的差别,用扫描电镜分析了试样的断口形貌特征。结果表明:FGH96合金的疲劳缺口敏感性随着温度的升高和应力比的增大而降低;与光滑试样的断口相比,合金的缺口试样在高温下疲劳裂纹多由加工刀痕起源,因此缩短了其疲劳萌生寿命;疲劳扩展区疲劳条带比较明显,扩展区面积比光滑试样小。
The notch fatigue properties of FGH96 powder of the second generation were investigated at 500 ℃ and 600 ℃. The curve of the original data was fitted to the SN curve, and the difference between Kf of the sample and the notch sample was analyzed. Electron microscopy analysis of the fracture surface features. The results show that the fatigue notch sensitivity of FGH96 alloy decreases with the increase of temperature and stress ratio. Compared with the fracture of smooth specimen, the fatigue crack of the notched specimen at high temperature is mainly caused by the machining marks , Thus shortening the fatigue life sprouting; Fatigue zone of fatigue extension zone is more obvious, the expansion zone area is smaller than the smooth sample.