Room temperature creep behavior has been investigated for typical stainless steels (SUS304, SUS430, SUS410L). The mechanism of creep is discussed in comparison with creep data on a carbon steel (SM400).
The results are summerized as follows:
1) Stainless steels showed creep deformation at a stress around 0.2% proof stress. Though creep rate decreased monotonously with increase in time, deformation did not ceased even at a time 1000 h. The creep curve of SUS304 steel followed a logarithmic creep law.
2) No creep was observed in steel SM400 below a critical strain rate at around 10^-8S^-1.
3) The facts that interstitial free steels showed room temperature creep, and that SUS304 steel showed no creep at 300°C suggest that the suppression of creep can be attributed to the dynamic strain aging due to the interaction between dislocation and interstitial carbon and nitrogen atoms.