The effects of Al upon the microstructure, stacking-fault energy, tensile properties and fracture surfaces of Fe-18Mn-0.6C-(0-2)Al twinning-induced plasticity steels were systemically investigated. The Al addition suppressed cementite precipitation during cooling after hot-rolling. The stacking-fault energy was linearly increased, with a constant slope of 7.8mJ/m2wt%Al. The Al addition increased the yield stress, reduction in area, uniform and post-uniform elongations while it decreased the amount and rate of strain hardening and dynamic strain aging. Although the post-uniform elongation of the TWIP steel without Al was almost zero, it was improved up to some 7% by adding 2wt%Al. This was comparable to those of dual-phase and TRIP steels having a similar tensile strength (780MPa).

Effects of Al on Microstructure and Tensile Properties of C-Bearing High Mn TWIP Steel. J.E.Jin, Y.K.Lee: Acta Materialia, 2012, 60[4], 1680-8