炼钢产品知识与质

1、分 类 方 法名 称区 分 要 素举例说明化学成分分类碳素钢工业纯铁C0.04%低碳钢C0.050.25%螺纹钢、角钢、普圆中碳钢C0.260.60%45#、50CrVA高碳钢C0.61%60Si2Mn合金钢低合金钢合金元素5%南钢全部中合金钢合金元素510%高合金钢合金元素10%不锈钢品质分类普通钢P0.045%，S0.050%螺纹钢、角钢、普圆优质钢P0.035%，S0.035%优圆、弹扁高级优质钢P0.030%，S0.030%部分出口弹扁冶炼方法炉别平炉钢/电炉钢转炉钢脱氧程度沸腾钢半镇静钢镇静钢南钢全部公称直径，mm实际重量与理论重量的偏差，%61271420522504牌号化学成分，

2、%CMnSiPSCeqHRB3350.251.600.800.0450.0450.52HRB4000.251.600.800.0450.0450.54HRB5000.251.600.800.0450.0450.55牌号公称直径mms（或p0.2）MPabMPa5%不小于HRB335625285033549016HRB400625285040057014HRB500625285050063012序号统一数字代号牌号化学成分，%CSiMnCrNiCu不大于110U20352350.32-0.390.17-0.370.50-0.800.250.300.2512U20452450.42-0.500.1

3、7-0.370.50-0.800.250.300.2513U20502500.47-0.550.17-0.370.50-0.800.250.300.2527U2145245Mn0.42-0.500.17-0.370.70-1.000.250.300.2531组别PS不大于，%优质钢0.0350.035高级优质钢0.0300.030特级优质钢0.0250.020755SiMnVB0.52-0.600.70-1.001.00-1.300.350.08-0.160.0005-0.00350.350.250.0350.035860Si2Mn0.56-0.641.50-2.000.60-0.900.35

4、0.350.250.0350.035960Si2MnA0.56-0.641.60-2.000.60-0.900.350.350.250.0300.0301255CrMnA0.52-0.600.17-0.370.65-0.950.65-0.950.350.250.0300.0301550CrVA0.46-0.540.17-0.370.50-0.800.80-1.100.10-0.200.350.250.0300.030SUP90.52-0.600.15-0.350.65-0.950.65-0.950.350.250.0350.035序号牌号物理性能ReLMPaRmMPaA%Z%硬度HBW脱碳层低倍表面质量755SiMnVB11751275525321不大于厚度的1.5-3.0%不得有缩孔、裂纹、分层、白点、气泡、翻皮及夹杂。一般疏松、中心疏松及偏析不超过2.5级钢材表面不得有裂纹、折叠、结疤、夹杂、分层、压入的氧化铁皮860Si2Mn12251370530321960Si2MnA1370157