以内压条件下含轴向内表面裂纹的管道为研究对象，通过引入x₀参数使J积分全塑性解与蠕变指数无关对Zahoor提出的蠕变断裂参数C^*估算方法进行改进；采用改进方法、Zahoor估算公式以及参考应力法中的R6整体解和Kim优化解计算不同蠕变指数和不同裂纹尺寸下的C^*值，并与有限元计算结果进行比较。结果表明：参考应力法所得C^*值比有限元计算结果大2～8倍，准确度较差；改进方法所得C^*值与有限元计算结果的比值在1左右，准确度较高；与Zahoor估算公式相比，改进方法在蠕变指数为3时的计算准确度更高，但随着蠕变指数增大， 2种方法的计算准确度趋于相同。

With axial internal surface cracked pipes under internal pressures as the research object, the creep fracture parameter C^* estimation method proposed by Zahoor was improved by introducing the x₀ parameter to make the J-integral full plastic solution independent of Norton indexes.The C^* values under the conditions of different Norton indexes and different crack size were calculated by the improved method, Zahoor solution, and reference stress methods including R6 global solution and Kim solution, and were compared with the finite element calculation.The results show that the C^* values calculated by the reference stress methods were two to eight times higher than those by the finite element calculation; the accuracy of the reference stress methods was poor.The ratios of the C^* values calculated by the improved method to the finite element calculation results were close to 1; the accuracy of the improved method was relatively high.Comparing with the Zahoor solution, the improved method had higher calculation accuracy with the Norton index of 3.But as the Norton index increased, the calculation accuracy of the two methods tended to be the same.