本发明公开屈服强度550MPa级运煤敞车用耐蚀钢及其制造方法。钢中含有C:0.049%~0.072%，Si:0.21%~0.29%，Mn:1.05%~1.39%,P≤0.018%,S≤0.006%，Als:0.015%~0.045%，Cr:0.45%~0.91%，Ni:0.11%~0.19%，Cu:0.27%~0.41%，Nb:0.018%~0.039%，Ti:0.015%~0.035%，Sb:0.046%~0.099%，Sn:0.034%~0.079%，Mo:0.11%~0.19%，B:0.0008%~0.0019%，Ca:0.0008%~0.0030%;余量为铁和不可避免的杂质;135~170mm板坯加热至1228~1249℃，粗轧温度>1100℃，精轧1000~1100℃开轧,830~895℃终轧，卷取温度580~650℃，钢板具有优异的耐硫酸和氯离子腐蚀性能。

The invention discloses corrosion-resistant steel its manufacturing method for coal carriage with a yield strength of 550MPa . The steel contains C:0.049%~0.072%，Si:0.21%~0.29%，Mn:1.05%~1.39%,P≤0.018%,S≤0.006%，Als:0.015%~0.045%，Cr:0.45%~0.91%，Ni:0.11%~0.19%，Cu:0.27%~0.41%，Nb:0.018%~0.039%，Ti:0.015%~0.035%，Sb:0.046%~0.099%，Sn:0.034%~0.079%，Mo:0.11%~0.19%，B:0.0008%~0.0019%，Ca:0.0008%~0.0030%, the balance is Fe and unavoidable impurities.This invention includes heating the 135~170mm thick slab to 1228~1249℃, then the rough rolling temperature should be greater than 1100℃, the finishing rolling start temperature is between 1000~1100℃, and the rolling is finished at 830~895℃. The final coiling temperature is 580~650℃, so that the steel plate has excellent resistance to sulfuric acid and chloride ion corrosion.