|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Advanced High-strength Steels
||Nanoprecipitate-hardened Fine-grained Twinning-induced Plasticity Steels with Excellent Cryogenic Strength-ductility Combinations
||Xuejun Jin, Yu Li, Wei Li
|On-Site Speaker (Planned)
Combined twinning-induced plasticity (TWIP) effect with nanoprecipitation hardening have been introduced in fine-grained high Mn austenitic steels for multiple strengthening-toughening mechanisms. The maraging steels show not only a significant improvement of yield strength (YS) larger than 900 MPa but also comparable tensile elongation of 50% at liquid nitrogen temperature (LNT), resulting from the combination of grain refinement and nanoprecipitation hardening. The introduction of nanoscale Nb-rich carbides aims at the following two aspects: (i) decreasing the high stacking fault energy (SFE) of austenitic matrix to the TWIP zone, thus resulting in plenty of stacking faults (SF) and deformation twinning with enhanced work hardening; (ii) refining the grain size magnitude further by deformed substructures. A sustainable TWIP effect can be delayed to the later deformation stage at LNT, due to a wide range of grain size distribution by SFs separation with intragranular carbides.
||Planned: Supplemental Proceedings volume