Q/BQB 310-2018 4 表 2 牌号 化学成分 a(质量分数) % C Si Mn P S Alt SAPH310 ≤0.10 ≤0.30 ≤0.80 ≤0.025 ≤0.020 ≥0.010 SAPH370 ≤0.21 ≤0.30 ≤1.00 SAPH400 ≤0.21 ≤0.30 ≤1.40 ≤0.025 ≤0.020 SAPH440 ≤1.60 SPFH540 ≤0.15 ≤0.50 ≤1.80 SPFH590 ≤0.18 ≤0.60 ≤2.00 ≤0.025 ≤0.020 SPFH780 ≤0.20 ≤1.00 ≤2.10 B440QK ≤0.21 ≤0.35 ≤1.80 ≤0.025 ≤0.020 B330CL ≤0.10 ≤0.30 ≤0.80 B380CL ≤0.12 ≤0.30 ≤1.50 ≤0.025 ≤0.020 B420CL ≤0.12 ≤0.30 ≤1.50 B450CL ≤0.10 ≤0.30 ≤1.50 ≤0.025 ≤0.020 B500CL ≤0.12 ≤0.30 ≤1.60 ≤0.025 ≤0.020 B530CL ≤0.12 ≤0.30 ≤1.60 ≤0.025 ≤0.020 B550CL ≤0.12 ≤0.30 ≤2.00 ≤0.025 ≤0.020 B600CL ≤0.15 ≤0.30 ≤2.00 ≤0.025 ≤0.020 B650CL ≤0.15 ≤0.50 ≤2.00 ≤0.025 ≤0.020 B320L ≤0.10 ≤0.30 ≤0.80 ≤0.025 ≤0.020 B420L ≤0.12 ≤0.50 ≤1.50 ≤0.020 B510L ≤0.16 ≤0.50 ≤1.60 ≤0.020 B510DL ≤0.18 ≤0.30 ≤1.60 ≤0.025 ≤0.020 B550L ≤0.16 ≤0.50 ≤1.60 ≤0.025 ≤0.020 B440QZR ≤0.12 ≤0.50 ≤1.30 ≤0.025 ≤0.020 - B480QZR ≤0.16 ≤0.50 ≤1.50 ≤0.020 a 为改善钢的性能,根据需要可添加其他合金元素,此时 Alt 的下限不要求。 表 3 牌号 化学成分 a(质量分数) % C Si Mn P S Alt 其他 QStE340TM ≤0.12 ≤0.50 ≤1.30 ≤0.025 ≤0.020 ≥0.015 Nb≤0.09 V≤0.20 Ti≤0.15 QStE380TM ≤1.40 QStE420TM ≤1.50 QStE460TM ≤1.60 QStE500TM ≤1.70 a 为改善钢的性能,根据需要可添加 Nb、V、Ti 中一种或几种合金元素,但 Nb+V+Ti≤0.22%。