Mechanical properties and strengthening mechanism of V-containing weathering steel

In order to insure atmospheric resistance and weldability, the carbon content of weathering steel was decreased. At the same time, increases in Mn content and V-N micro-alloying were adopted to increase the strength of weathering steel in this paper. The results indicate that when the mass fraction of Mn is 1.36%, the yield strength increases to 435 MPa, and the contribution of fine grain strengthening and dislocation strengthening to the yield strength is 59.8%. When the yield strength reaches 555 MPa, V-N alloyed weathering steel has good precipitation strengthening and fine grain strengthening effects, and the sum of the two mechanisms contributes more than 70% of the yield strength of the two groups of V-N alloyed weathering steel.