|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Advanced High-Strength Steels
||High Strain Rate Deformation of High-Mn and Medium-Mn TWIP-TRIP Steel
||Jake Benzing, Whitney Poling, Dean Pierce, Kip Findley, Dirk Ponge, Dierk Raabe, James Wittig
|On-Site Speaker (Planned)
Servo-hydraulic tension was utilized to study the effects of strain rate (0.02–200 strain/s) on mechanical properties and deformation mechanisms in twinning and transformation-induced plasticity [TWIP-TRIP] steels. A fully austenitic Fe-25Mn-3Al-3Si alloy possesses an intermediate stacking fault energy [SFE] of 21±3 mJm-2 such that a combination of TWIP and TRIP is promoted, which provides obstacles to subsequent dislocation motion. To correlate TWIP-TRIP distributions to changes in strain rate, (at the same interrupted strain), dark field transmission electron microscopy, electron channeling contrast imaging and electron backscattered diffraction were used to quantify the spacing and thickness of planar defects. A medium-Mn alloy, (Fe-12Mn-3Al-0.06C), has been designed via Thermo-Calc predictions to optimally balance composition, phase fraction/stability, SFE and intercritical annealing. High strain rate mechanical testing of the already processed medium-Mn alloy is currently in progress. Additional characterization involves x-ray diffraction and scanning-TEM energy-dispersive spectroscopy to respectively quantify phase fraction and alloy segregation.
||Planned: Supplemental Proceedings volume