Armored vehicles are primarily designed to provide protection against blast and ballistic events and secondly to improve the manoevrability in battlefield. The manoevrability can be materialized by weight reduction of the vehicles, which also leads to the decrease in operating cost. To obtain improved performance without compromising blast and ballistic properties, explosion bulge testing was adpoted in this work to strengthening a austenitic twinning-induced plasticity (TWIP) steel. The pre-blast technique significanly reduced the grain size of the material which increased the hardness.The electron backscattered diffraction (EBSD) was conducted to study the microstructure and the dominant deformation mechanism was found to be dislocation slips. As a result, it was found that soft materials like TWIP steel lost a minimal toughness but showed strongly work-hardened after blasts. Based on this result, it is possible that the lifecycle of armor vehicles could be significantly expanded and the repair cost could be greatly reduced.