在不同温度T和不同应力σ下对25Cr35Ni耐热钢进行蠕变试验，引入参数P对不同蠕变应变下的温度和时间进行归一化处理，分析了（P，σ）数据点随蠕变应变的变化规律，引入参数Z_c分析了数据的分散程度并使用蠕变应变为5.0%下的试验数据对持久寿命进行了预测。结果表明：随蠕变应变的增加，σ-P曲线趋近于断裂曲线，Z_c先迅速增大后趋于稳定，（P，σ）数据点与其对应拟合曲线的偏差减小；基于Z_c参数法预测得到的持久寿命与实测持久寿命接近，数据分散程度较小。

Creep tests were conducted on 25Cr35Ni heat-resistant steel at different temperatures T and different stresses σ. The temperature and time at different creep strains were normalized by introducing parameter P. The variation of (P,σ) data point with creep strain was analyzed. Parameter Z_c was proposed to analyze the dispersion degree of data and to predict the creep rupture life with experimental data at creep strain of 5.0%. The results show that with increasing creep strain, the σ-P curve became close to the fracture curve; the value of Z_c increased rapidly and then became stable; the deviation between (P,σ) data point and the corresponding fitting curve decreased. The predicted rupture lives on basis of Z_c parameter method were close to the experimental rupture lives; the dispersion degree was relatively small.