Tensile tests were used to investigate the effect of grain size on the strain-induced martensitic transformation start temperature in metastable austenitic steel with special attention to ultrafine grain size. The austenite grains were refined to submicron size by the strain-induced martensite and its reverse transformations (SIMRT), which occurred during a conventional cold rolling and annealing process. The start temperature of the straininduced martensitic transformation was linearly lowered with a decrease in austenite grain size, even down to submicron grain sizes. This result is due to the decrease in grain size causing an increase in the temperature dependency of the strain-induced martensitic transformation and higher austenite stability brought about by grain refinement.
Bibliographical noteFunding Information:
The authors gratefully acknowledge the support of the sponsors of the Advanced Steel Processing and Products Research Center, an industry/university cooperative research center at the Colorado School of Mines and the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Commerce, Industry and Energy, Republic of Korea.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Mechanics of Materials
- Metals and Alloys
- Materials Chemistry