公路桥梁桩管钢在液-固环境中的腐蚀行为研究

Study on Corrosion Behavior of Pile Pipe Steels of Highway Bridge in Liquid-Solid Environment

研究了合金化元素和热处理对桩管钢显微组织、力学性能和耐腐蚀性能的影响。结果表明,除调质态0.18Mo+0.9Cr和0.18Mo+1.8Cr桩管钢组织为回火索氏体外,其余热轧态桩管钢的组织都为铁素体和珠光体;调质态0.18Mo+0.9Cr(QT)和0.18Mo+1.8Cr(QT)试样具有较高强塑性同时,冲击功分别达到156 J和152 J;Cu+Cr和Mo+Cr元素的添加有助于提高桩管钢的耐蚀性能,且经过调质热处理后,0.18Mo+0.9Cr(QT)和0.18Mo+1.8Cr(QT)管桩钢的耐蚀性能会进一步改善,而W+Cr元素的添加会降低桩管钢的腐蚀性能;0.18Mo+0.9Cr(QT)桩管钢的极化电阻明显高于20桩管钢,说明0.18Mo+0.9Cr(QT)桩管钢的耐腐蚀性能要高于20桩管钢,在腐蚀过程中不容易发生腐蚀,这与失重腐蚀测试结果相吻合。0.18Mo+0.9Cr(QT)桩管钢在具有较高强塑性与冲击韧性的同时,具有良好的耐腐蚀性能。

The effects of alloying elements and heat treatment on the microstructure,mechanical properties and corrosion resistance of pile pipe steels were studied.The results show that,except the microstructure of quenched and tempered0.18 Mo+0.9 Cr and 0.18 Mo+1.8 Cr steels is tempered sorbitie,the microstructure of the other hot-rolled pilesteels are ferrite and pearlite,and the quenched and tempered 0.18 Mo+0.9 Cr(QT)and 0.18 Mo+1.8 Cr(QT)specimens have high strength plasticity and the impact energy is 156 J and 152 J respectively.The addition of Cu+Cr and Mo+Cr elements can improve the corrosion resistance of pile pipe steel,after quenching and tempering heat treatment,the corrosion resistance of 0.18 Mo+0.9 Cr(QT)and 0.18 Mo+1.8 Cr(QT)pipe pile steel is further improved,while the corrosion resistance of pile pipe steel decrease by adding W+Cr.The polarization resistance of 0.18 Mo+0.9 Cr(QT)pipe steel is obviously higher than that of 20 pile steel,and it shows that the corrosion resistance of 0.18 Mo+0.9 Cr(QT)pile pipe steel is higher than that of 20 pile pipe steel.It is not easy to corrode in the process of corrosion,which is consistent with the results of weightlessness corrosion test.0.18 Mo+0.9 Cr(QT)pile pipe steel has high strength plasticity,impact toughness and good corrosion resistance.