| Constant-stress creep tests at temperatures of 913,953 and 993 K over a stress range of 140 to 230 MPa were made on AISI 316 stainless steel to investigate the effect of recrystallization occurring during creep. The best creep properties were obtained in the specimens which had been pre-stained 207% arid tested at 953 K under a stress in the range of 147-170 MPa. Above 30% pre-strain the creep properties gradually deteriorated, which was attributed to partial recrystallization. The carbides in the partially recrystallized specimens,0.1-0.3㎛ large, did not coalesce during creep but remained dispersed in the grains and grain-boundaries. In the 30% pre-strained condition, the best creep properties were obtained with the creep stress of 200-230 MPa at 953k. The creep resistance was considerably reduced by 40% pre-strain. It was responsible for the coarsening of carbides and the formation of subgrains. |
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