Strain Hardening and Strain Rate Sensitivity Behaviors of Advanced High Strength Steels

The mechanical properties of commercial dual phase （DP）, transformation induced plasticity （TRIP）, and high strength low alloy （HSLA-340） steel sheets are investigated and compared at various strain rates ranging from 0.001 7to 0.17 s-1 at ambient temperature.TRIP steel outperforms the other two materials , having comparable ductility and twice as large strength relative to DP steel.TRIP has larger strength and much larger ductility than HSLA-340.The exceuent ductility of TRIP800is due to its high strain hardening capability , which promotes stable plastic deformation.It is observed that the strain hardening rate in TRIP800does not decrease to zero at failure , as common in most materials in which failure is preceded by necking.