稀土含量对25CrMoA抽油杆钢硬度及腐蚀性能的影响

Effect of rare earth on hardness and corrosion property of 25CrMoA sucker rod

采用真空感应炉,以25CrMoA为母材冶炼了不同稀土含量的25CrMoA-RE抽油杆钢;采用金相显微镜观察了样品的金相组织,同时采用洛氏硬度仪和电化学方法分别测量了不同稀土含量的25CrMoA-RE钢的洛氏硬度和极化曲线。研究结果表明,适量的添加稀土元素可以细化金相组织,提高25CrMoA钢的硬度和耐腐蚀性,当稀土质量分数达到0.15%时硬度值达到24.8HRC;腐蚀电流从56.03 mA/mm^2降至13.64mA/mm^2。

The vacuum induction furnace is used to melt 25CrMoA sucker rod steel with different amount of rare earth. The effects of rare earth on metallographic structure, rockwell hardness and corrosion of steel 25CrMoA are studied by the use of optical metallography, rockwell hardness measurement equipment and elec- trochemical technique respectively. The results show that：the appropriate addition of rare earth can refine the microstructure, increase the hardness of steel 25CrMoA, and the hardness are the best with rare earth content of 0. 15%, the corrosion resistance of the steel is improved, and the corrosion current is decreased to 13.64 l, nA/mm2 .