A study on influence factors of small punch creep test by experimental investigation and finite element analysis

Small punch creep (SPC) tests for SUS304 and Cr5Mo specimens with dimension Ø10 mm × 0.5 mm were performed at different temperatures, load levels and atmospheres. Based on these tests, a finite element model (FEM) combined with modified Kachanov–Rabotnov (K–R) creep damage constitutive equations was established to simulate the ductile and creep damage of the round specimen during the test procedure. The validity of FEM was proved by the comparison of Center deflection–Time data yielded from finite element analysis (FEA) and experiment. Then, effects of sample thickness, load level, ceramic ball diameter, specimen diameter, temperature and protective atmosphere on SPC test were analyzed by experimental investigation and FEA. The results show that five of the six above-mentioned factors (except specimen diameter) influence the rupture time, center deflection, real creep strain and creep damage of SPC specimen strongly.