Experimental study and numerical simulation of creep damage of small punch creep test specimen of SS304 stainless steel

The finite element model was established based on the small punch creep test of SS304 steel specimen in the condition of constant temperature and different loads. The variation of central deflection and creep strain with time and the evolution of creep damage subjected to constant forces were analyzed using FEM incorporated with modified K-R creep damage constitutive equations. The test results were in agreement with those of numerical simulation and three different stages appeared in the curve of central creep, which was quite similar with conventional creep tests. The results also showed that the creep damage at the central part was high, and localization of damage was obvious. Initial failure occurred at the bottom surface, 0.8 mm away from the center which agreed well with the observation from the test.