We investigated the effect of preexisting plastic deformation with the strain of 30% on the creep behavior of TP347 austenitic steel at 650. °C with different applied stresses. The results showed that the creep rupture life of the prestrained sample increased more than that of the unstrained sample tested at 300, 250 and 200. MPa due to the strengthening of the mechanical twins induced by preexisting plastic deformation. Conversely, the prestrained samples were ruptured earlier than that of the unstrained sample tested when the lower creep stresses (150 and 125. MPa) were applied. The shorter creep rupture life of the prestrained sample was due to the reduced amount of time to a minimum creep rate and the shorter tertiary-stage creep time which can be related to the accelerated precipitation of sigma phase at the grain boundaries in the strained sample.
Bibliographical noteFunding Information:
The authors gratefully acknowledge the financial support provided by the Korea Government Ministry Of Trade, Industry & Energy through the Korea Institute of Energy Technology Evaluation and Planning (Grant no. 2013101010175A and 20151110100040 ), and the Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT and future Planning (Grant no. 2015R1A2A2A04006933 ).
© 2015 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering