|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Materials Processing Fundamentals
||D-48: Effects of Mn Content on the Formation of Nanoscale Precipitates and Matrix Microstructure in the Ultra-high Strength Steels
||Songsong Xu, Yu Zhao, Hao Guo, Naimeng Liu, Xinghao Wei, Zhongwu Zhang
|On-Site Speaker (Planned)
The critical role of Mn content in the formation of nanoscale precipitates and matrix microstructure in the ultra-high strength steel has been examined through a combination of three dimensional atom tomography and small-angle neutron scattering. With the increase of Mn content from 6% to 9%, the single phase ferrite in the steel would transform to dual-phase (ferrite and retained austenite), leading to the dissolution of precipitates in the converted single ferrite. The results showed that nanoscale precipitates consisted of a Cu-riched bcc core partially encased by a B2-order Ni(Mn,Al) phase, had similar size in the 6% and 9% Mn steels. The number density in the 9% Mn steels was obviously less than that in the 6% Mn steels due to the extinction of precipitates in the retained austenite. Finally, the synergistic effects of nanoscale precipitates and the retained austenite on the mechanical properties have been discussed by quantitative calculation of strengthening mechanism.
||Planned: None Selected