本文对交流电位法测定高温疲劳裂纹扩展进行了试验研究。结果表明:疲劳裂纹扩展的相对增量与电位的相对增量之间存在线性关系,这样,就可从自动记录的电位-循环周次曲线(V-N曲线)求得裂纹长度-循环周次曲线(a-N曲线)。此法简便可靠、灵敏度高、稳定性好,值得推广。 In this paper, the experimental study of high temperature fatigue crack growth measured by AC potential method was carried out. The results show that there is a linear relationship between the relative increase in fatigue crack growth and the relative increase in potential so that the crack length-cycle weekly curve (VN curve) can be found from the automatically recorded potential-cycle weekly curve aN curve). This method is simple and reliable, high sensitivity, good stability, it is worth promoting.