Abstract: Test pipeline steel X70 (/%: 0. 12C, 0. 20Si, 1.60Mn, 0. 005P, 0. 005S, 0. 10V, 0. lONb, 0 〜 0. 15RE) is melted by a 10 kg vacuum induction furnace. The corrosion behavior of pipeline steel X70 with micro-RE in 0. 1 mol/L Na₂SO₄ water solution is studied by electrochemistry and weight loss method. Results show that the micro-RE addition obviously decreases corrosion current i_corr of pipeline steel and improves morphology of corrosion surface. With increasing RE addition, the corrosion current decreases and as RE content in steel increases from 0 to 0. 10% the corrosion rate of steel decreases from 7. 03μg/ (cm². day) to 0. 29μg / (cm²・ day). The suitable RE addition is 0. 10%.

摘要： 试验用X70管线钢(/%:0.12C、0.20Si、1.60Mn、0.005P、0.005S、0.10V、0.10Nb、0～0.15RE)用10kg真空感应炉冶炼。采用电化学和失重分析法研究了微量稀土对X70管线钢在0.1 mol/L Na₂SO₄水溶液中的腐蚀行为。试验结果表明,微量稀土可降低管线钢腐蚀电流i_corr,改善腐蚀形貌。随着稀土加入量的增加,腐蚀电流减小,当钢中的RE含量由0增加至0.10%时腐蚀速率由7.43μg/(cm².day)降至0.29μg/(cm².day)。稀土的最适宜加入量是0.10%。