5. Results
5.1. Creep behavior analysis
The obtained creep curves are shown in Figure 1, and the obtained minimum creep rate and rupture time are summarized in Table 2. The rupture time varies from 17 hours to 942 hours, which increases with the decrease of the applied stress at the same temperature. It can be seen from specimens 8, 13, and specimens 9, 14, 15 that obvious scatter of creep data exists. The origin of the scatter comes from many sources, such as the fluctuation of test conditions, surface roughness, grain size and inhomogeneous microstructure41,42.