1.0 GPa low carbon medium Mn heavy steel plate with excellent ductility

A vanadium-bearing medium Mn heavy steel plate was designed, and the yield strength reaches around 1.0?GPa and the total elongation reaches around 18% after the annealing treatments. Meanwhile, the steel also possesses relatively good cryogenic impact toughness. Although the dislocation density of ?2.65???10(14)?m(?2) in the hot-rolled steel decreases to ?1.13???10(14)?m(?2) in both annealed steels and the volume fractions of retained austenite reach ?7.9% and ?13.5% for the steels annealed at 620?C for 1 and 2?h, there is no or small decrease in yield strength owing to numerous nanometer-sized carbides precipitated in martensite matrix. This paper is part of a Thematic Issue on Medium Manganese Steels.