Stacking fault energy and plastic deformation of fully austenitic high manganese steels: Effect of Al addition

Evolution of Compositions and Properties of CaO–SiO₂ Based Mold Flux for Continuous Casting High Mn Steel

“…1,2) Additionally, the addition of Al into high Mn steel has shown the extraordinary mechnical properties since it is indispensable to increase the stacking fault energy and suppress delayed fractures in the press-formed parts of twin-induces plasticity (TWIP) steel. [3][4][5] However, a range of issues with the poor casting performance are found during casting process due to the interfacial reaction between molten steel and mold flux, which changes slag composition and deteriorates lubrication and heat transfer between solidifying shell and mold, inducing severe depressions, cracks, and even breakout. [6][7][8][9] Recent studies focusing on the reaction mechanism between the conventional CaO-SiO 2 type mold flux and molten steel with high contents of Mn and Al have noted that the concentration of Al in the steel has the most significant influence on the interfacial reaction, resulting in the Al 2 O 3 accumulation in the mold flux.…”

Characterization of Evolution of Microscopic Stress and Strain in High-Manganese Twinning-Induced Plasticity Steel

“…[1][2][3][4] As the mechanical properties of these steels are often related with the formation of mechanical twins by deformation, these steels are called twinning-induced plasticity (TWIP) steels. The mechanical properties, [5][6][7][8][9][10][11][12][13][14][15] deformation mechanisms associated with stacking fault energies (SFE), [16][17][18][19][20][21][22][23] the thermodynamic properties, 24,25) and the microstructure [26][27][28][29][30][31] of the TWIP steels have been extensively investigated. Since a stacking fault may act as an embryo of a twin, the SFE or the chemical composition of the alloying elements, such as manganese, carbon, silicon, and aluminum, is an important factor affecting the twinning processes caused by plastic deformation.…”

Strain Hardening Behavior and Microstructure Evolution of High-Manganese Steel Subjected to Interrupted Tensile Tests

“…The planar glide became more evident as the SFE increased by suppressing or delaying mechanical twinning. As the SFE is increased by Al addition, the critical stress for initiation of the mechanical twinning becomes higher [20]. It was also reported [21,22] that Al additions lead to a lower strain hardening rate and decrease the frequency of mechanical twins formation, resulting in a decrease in tensile strength.…”

“…No deformation twins were observed (Figure 4a,b). Dislocation activity always occurs before the twinning mechanism [20,25]. The twinning deformation will start when the stress concentration, which is provided by piled-up dislocations, surpasses the critical stress for deformation twins [21].…”

“…Aluminum addition strongly increases SFE, whereas silicon causes an opposite effect. Park et al [20] reported that, regardless of the SFE and/or the Al content, deformation was achieved by planar glide of dislocations before mechanical twinning occurred. The planar glide became more evident as the SFE increased by suppressing or delaying mechanical twinning.…”