高性能耐候桥梁钢的开发及应用

Development of Weathering Bridge Steel with High Performance and Its Applications

采用低碳及合金化成分设计,利用TMCP+回火工艺,开发出HPS 485W耐腐蚀桥梁钢。利用拉伸、冲击、弯曲、扫描电镜和EBSD等手段,研究了钢板的组织和性能。结果表明,HPS 485W熔炼成分、钢板探伤、耐大气腐蚀指数(I值≥6.5)及力学性能均满足标准要求,组织为铁素体和贝氏体,铁素体含量达到62.7%,平均晶粒尺寸仅为2.95μm,保证钢板具有良好的抑制裂纹扩展的能力以及桥梁结构长期服役的安全性。

The HPS 485W corrosion-resistant bridge steel was developed based on the composition design with low carbon and alloying elements by using the TMCP plus tempering process.And then its microstructures and properties of steel plates made of the steel were studied by such methods as tensile test,impact test,bend test,scanning electron microscopy and EBSD.The study results showed that the melting compositions in the HPS 485W steel,flaw detection of steel plates made of the steel,atmospheric corrosion resistance index(I value≥6.5)and mechani-cal properties of the steel met the requirements asked by standards.The microstructure of the steel was composed of ferrite and bainite,whose ferrite content accounted for 62.7%,while the average grain size of the steel was only 2.95μm,which guaranteed the good ability to suppress the crack propagation of steel plates made of the steel and the safety of bridge construction in long-term service.