| Title |
Effect of Thermo-mechanical Treatment on the Formation Behavior of Martensite in 316L Stainless Steel |
| Authors |
김종식(Jong-sig Kim); 김재남(Jae-nam Kim); 강창룡(Chang-yong Kang) |
| DOI |
https://doi.org/10.3365/KJMM.2018.56.4.265 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
thermo-mechanical treatment; 316L stainless steel; α -martensite; ε-martensite; TEM; EBSD |
| Abstract |
This study was carried out to investigate the effect of thermo-mechanical treatment on the formation behavior of martensite in 316L stainless steel. Dislocation, α and ε-martensite were formed by thermo-mechanical treatment. Martensite with surface relief and specific direction was formed by thermomechanical treatment. Martensite formed by thermo-mechanical treatment were reversed to austenite with an ultra-fine grain size of less than 1 μm by annealing treatment at 700℃ for 20 min. α -martensite with a K-S orientation relationship and ε-martensite with a [110] γ [100]ε orientation relationship to the matrix was formed by thermo-mechanical treatment. The volume fraction of dislocation, α and ε-martensite were increased with the cycle number of thermo-mechanical treatment. In 5-cycle number thermo-mechanical treated specimens, more than 25% of the volume fraction of α -martensite and less than 5% of the volume fraction of ε-martensite were attained. The austenite grains were fairly deformed by thermo-mechanical treatment and the grain size of austenite with various orientation relationship were changed from micrometer to sub-micrometer by the 5-cycle thermo-mechanical treatment. |