材料期刊网

The effects of over aging (OA) and vanadium on microstructure and properties of cold-rolled low-carbon Si-Mn vanadium-bearing and traditional dual-phase steel sheets are studied. The results show that the microstructure and mechanical properties of DP steels are greatly affected by over-ageing temperature. When OA below 250℃, the elongation rate increases sharply whiles both the yield strength and tensile strength decrease slightly, this is favorable to the increase of all over mechanical properties. After OA above 300℃, elongation does not increase much, but the yield strength increases and tensile strength decreases, which deteriorate the mechanical properties of the steel. Finally, the results also show that both the hardenability and the tempering stability of steel can be significantly improved by vanadium micro-alloying.