MECHANICAL ANISOTROPY OF COLD-ROLLED ST-37 STEEL PLATE UNDER HIGH STRAIN RATES LOADINGS

Cold rolling process in metal could increase its strength and hardness, but also induces mechanical anisotropy. This is caused by unresolved plastic strain microstructural changes deformation exerted pair of rolls at a relatively low temperature. research aims to provide understandings on anisotropic rate sensitive behaviour St-37 mild steel. The microstructure rolled unrolled plate were observed 3 directions relative the direction. cylindrical specimens then prepared from with 33.3% reduction orientation 0o, 45o, 90o Specimens as comparison same directions. These tested compression loading, first quasi-static condition, using Split-Hopkinson Pressure Bar (SHPB) 1200 s-1. experimental results form stress-strain curves are used obtain parameters Simplified Johnson-Cook viscoplastic model. anisotropy yield be seen both high where highest found perpendicular In addition, effect cold sensitivity material captured successfully this study, show less compared specimens.