Figure legend: Unprecedented combination of yield strength and elongation exhibited in a series of ultrahigh-strength and high-ductility, light-weighted FeMnAlC alloys (indicated by symbols) and deformation mechanism manifested by bursting dislocations in the austenite nano-channels (TEM image).
Journal of Alloys and Compounds, Volume 586, 2014, Pages 616–620.
Chih-Lung Lina, Chuen-Guang Chaoa, Jenh-Yih Juangb, Jenn-Ming Yangc, Tzeng-Feng Liua
a Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan and
b Department of Electrophysics, National Chiao Tung University, Hsinchu, Taiwan and
c Department of Materials Science and Engineering, University of California, Los Angels, CA, USA.
The deformation mechanisms of a bulk nanostructured Fe–30Mn–9.5Al–2.0C (in wt.%) alloy were investigated. After aging at 450 °C for 9–12 h, the alloy exhibits an exceptional strength-ductility combination (e.g. yield strength ∼1406 MPa with elongation ∼32%). The aged alloy exhibits a novel microstructure with isolated austenite nano-channels bounded by an extremely high volume fraction of directional nano-sized (Fe,Mn)3AlC carbides (κ′-carbides). The plastic deformation was found to be dominated by bursting dislocation nucleation within the isolated austenite nano-channels.