980 MPa耐蚀钢轨U68CuCr的开发和应用

通过制定合理成分和铁水脱硫-120 t顶底复吹转炉-吹氩-LF—RH-280 mm×380 mm坯连铸-轧制工艺,开发了980 MPa热轧耐蚀钢轨U68CuCr（/%:0.65~0.75C，0.40~0.80Si，1.00~1.30Mn，≤0.030P，≤0.025S，≤0.50Cu，≤0.50Cr，≤0.05Nb）。试验结果表明,耐蚀钢轨U68CuCr抗拉强度≥1060 MPa,伸长率≥12%,踏面硬度HB值为300~310,珠光体片间距为0.2μm,耐磨性能优于同一强度级别的U75V钢轨。2%NaCl溶液腐蚀试验显示,耐蚀钢轨U68CuCr腐蚀速率为U75V钢轨的57%。在京广线使用3年,通过总重量超过3亿吨,耐蚀钢轨U68CuCr使用性能良好,其各项指标均满足铁路运输要求。

Development and Application of 980 MPa Corrosion-Resistant Rail Steel U68CuCr

The 980 MPa hot rolled corrosion-resistant rail steel U68CuCr (/% ： 0.65-0.75C, 0.40-0.80Si, 1.00-1.30Mn, ≤0.030P, ≤0.025P, ≤0.50Cu, ≤0.50Cr, ≤0.05Nb) is developed by defined the chemical composition and the desulphurized metal-120t top and bottom combined blown converter-argon blowing- LF-RH-280 mm x 380 mm bloom casting-rolling process. Test results show that the tensile strength of corrosion-resistant rail steel U68CuCr is ≥1060 MPa with elongation ≥12% , the hardness HB value of rolling face is 300-310, the interlamellar spacing of pearlite is 0.2 μm, and the wear resistance is better than that of U75V rail steel with same strength rating. The results of 2% NaCl corrosion test show that the corrosion rate o£ rail steel U68CuCr is 57% of that of rail steel U75V. The corrosion-resistant steel U68CuCr rail has better serve performance in Beijing-Guangzhou railway line for 3 years with gross transporting load 0.3 billion t, and all properties of steel U68CuCr rail meet the requirement of rail.