赵国昌, 张海军, 刘生, et al. Research and application of on Line Direct-Quenching (DQ) Process for 500 MPa S500QL High Strength Quenching and Tempering Steel Plate[J]. Special Steel, 2021, 42(3): 57-62.
赵国昌, 张海军, 刘生, et al. Research and application of on Line Direct-Quenching (DQ) Process for 500 MPa S500QL High Strength Quenching and Tempering Steel Plate[J]. Special Steel, 2021, 42(3): 57-62.DOI:
Low carbon (C≤0. 12%) Nb-V microalloying S500QL high strength steel plate has been developed. And 15 ~50 mm steel plate is produced by two-stage controlled rolling (first stage rolling at 950 ~ 1 070 ℃
second stage started rolling at ≤890℃ and finishing rolling at ≤850 ℃
on-line cooling direct-quenching( DQ) with 7 ~20 ℃/s after rolling
and tempering at 620 - 670 ℃ for 3 min/ (mm • T)
clean steel smelting process with 120 t BOF + LF + VD. The steel plate has fine granular bainite + small amount of proeutectoid ferrite with yield-tensile strength ratio ≤0. 90
elongation A≥19% and impact energy at -50℃ ≥100 J to meet the market demand. And the welding crack sensitivity test and the welding joint property test of DQ process steel plate was carried out. The results show that the steel plate produced by this process has good welding property.