Development of High Strength Weathering Steel Q450 NQR1 Containing Vanadium

The high strength weathering steel Q450 NQR1 contaning vanadium was developed through TMCP process. Laboratory test results indicate that the microstructure of plate is ferrite-pearlite and grain size rating is ASTM No. 12,the yield strength,tensile strength,yielding-to-tensile ratio and specific elongation are 493.57 MPa,599.00 MPa,0.823 9,30.21%,respectively. The impact absorbing energy at -80℃ and -40 ℃ are 51.6 J and about 92 ~97 J,respectively. The corrosion rate for 72 hours and 144 hours are 44.47% and 34.06% compared with the Q345 B,respectively. The developed steel can meet the requirement for the railway boxcar.