低合金结构钢（GB1591-88）（一） 1、用途：适用于一般结构和工程用钢板、钢带、型钢和棒钢。
其对化学成分所作的规定也 适用于钢锭（包括连铸坏）、钢坏及其制品。
2、化学成分
化学成分（%）S(硫) P(磷) 牌号Mn(锰) Si(硅) Ti(钛) Nb(锯) RE 加入 C(碳) V(钒) Cu（铜) N(氮)量M 09MnV≤0.120.8-1.200.20-0.50.04-0.1+000.015
52 09MnNb≤0.120.08-1.200.20-0.50.015-0.050.0450.015
50 09Mn2≤0.121.40-1.800.20-0.50.0450.045
5 12Mn91°0-6001.10-1.500.20-0.510.0450.045
5 18Nb0.14-0.220.1-1.800-21OS00-.015
70 09MnCuP≤0.121.00-1.800.20-0.5≤0.030.20-0.400.0450.05-0.1 TiV52 10MnSiCu≤0.121.25-1.600.80-1.10.15-0.300.0450.045
0 12MnV≤0.151.00-1.400.20-0.510-10°0S000.015
52 14MnNb0.12-1.180.80-1.200.20-0.50.015-0.05000.015
50 16Mn0.12-0.201.20-1.600.20-0.50.0450.045
5 16MnRE0.12-0.201.20-1.600.20-0.5070-2000.0450.045
5 10MnPNb≤0.140.80-1.200.20-0.50.015-0.05070-00S+0°00.006-0. RE5012 15MnV0.20-0.50.04-0.0I+000.015
0.12-0.181.20-1.6052 15MnTi810-7101.20-1.600.20-0.50.125-0.000.045
523 16MnNb0.12-0.201.00-1.400.20-0.50.015-0.050.0450.015
50 14MnVTi≤0.181.30-1.600.20-0.51'0-+0°00.09-0.10000 RE506 15MnVN0.12-0.201.30-1.700.20-0.5Z'0-0100.010-0.S000.045
50020 注：①钢材和钢坏（包括连铸坏）的化学万分的允许偏差应符合GB222-84的规定。
②平炉冶炼的钢硫含量：优质钢≤0.035%，高级优质钢≤0.025%
3、物理性能①
180°弯冲击试验 钢材厚抗拉强度0屈服强度0s伸长曲试验V型冲击 牌号度或直率8d=弯心直温度功（纵
径(mm）(%)≥径a-试(C)向)①)
MPa kgf/mm² MPa kgf/mm²样厚度W 09MnV≤16430-58043-582953023d=2a2027
>16-2527528d=3a 09MnNb≤16410-56041-562953024d=2a2027
>16-25390-54039-542752823d=3a ≤16440-59044-592953022d=2a 09Mn2>16-25420-57042-572752822d=3a2027
>30-100410-56041-562552621d=3a 方、圆钢 ≤16440-59044-592953022d=2a >16-25430-58043-582752821d=3a 12Mn>25-36400-55040-552552621d=3a2027
>36-50390-54039-542352421d=3a >50-100339-54034-542352420d=3a 方、圆钢 18Mb≤16470-62047-523453520d=2a2027
>16-25450-60045-603253319d=3a 09MnCuPTi91>490-64049-643453522d=2a2027
>16-25490-64049-643353421d=3a 4-10490-64049-643453522d=2a 10MnSiCu>10-20470-62047-623353422d=2a2027
>20-32470-62047-623253322d=3a 12MnV≤16490-64049-643453522d=2a2027
>16-253353421d=3a 14MnNv≤16490-64049-643553621d=2a2027
>16-25470-62047-623353420d=3a ≤16510-66051-663453522d=2a >16-25490-64...
