采用旋转弯曲的加载方式，评价了 Ti-47．5Al-2．5V-1．0Cr-0．2Zr （原子分数／％）合金择优取向层片组织的高温高周疲劳性能，并对疲劳断口进行了扫描电镜分析。结果表明：该合金表现出符合 Basquin 方程的平直 S-N 曲线，750℃条件疲劳极限相当于其抗拉强度的60％；断口观察发现，所有试样中的疲劳裂纹均以穿层片方式扩展，表明该种组织的界面对疲劳裂纹扩展具有较高的抗力。
The high-cycle fatigue performance of Ti-47.5Al-2.5V-1 .0Cr-0.2Zr (at.%)alloy with a preferentially oriented lamellar microstructure has been evaluated by means of load-controlled rotating bending fatigue tests at elevated temperature,and fracture sur-faces of fatigue specimens were also analyzed by scanning electron microscope.The results show that it exhibits a flat S-N curve fitted by Basquin equation,and its fatigue limit is equal to 60% of the ultimate tensile strength at 750 ℃.The fracture surface observation proves that all of the fatigue crack propagation in the studied samples is indeed presented with a typical translamellar mode,and indica-ting the high resistance of this microstructure to crack propagation.
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