目的 研究强流脉冲电子束（HCPEB）对50BA钢表层组织和表面耐腐蚀性能的影响。方法 对50BA钢进行不同脉冲次数的表面处理，用扫描电镜观察组织变化，并在NaCl和去离子水配成的3.5%NaCl腐蚀溶液中（室温）进行动电位极化曲线测试。结果 经HCPEB处理后，50BA钢试样表层晶粒细化且产生了细小均匀分布的针状马氏体，随着脉冲次数的增加，表面趋于光滑。试样表面的自腐蚀电位从?0.660 V提高到?0.629 V，腐蚀电流从1.48×10?6 A降低到8.36×10?7 A。随着脉冲次数的增加，试样表面的腐蚀电流降低，腐蚀电位升高，腐蚀速率降低，腐蚀倾向性减小，其中50次脉冲处理后试样表面的耐蚀性能最好。结论 经HCPEB处理后，表层组织发生相转变，表面趋于光滑和获得的均匀细小针状马氏体从理论上解释了50BA钢耐腐蚀性能的提高。为了提高50BA钢的耐腐蚀性，应将脉冲次数控制在30次以上，且越高越好。

The work aims to study the effects of high current pulsed electron beam (HCPEB) on microstructure and corrosion resistance of 50BA steel surface. Surface treatment was carried out to 50BA steel for different pulse times, organizational change was observed with a scanning electron microscope, and in 3.5wt% NaCl solution prepared using NaCl and deionized water (room temperature) for dynamic polarization measurement. After HCPEB treatment, grains on the surface of 50BA steel specimen were refined, and a fine and uniformly distributed acicular martensite was produced. With the increase of pulse number, the surface tended to be smooth. Self-corrosion potential of sample surface increased from ?0.660 V to ?0.629 V while the corrosion current decreased from 1.48×10?6 A to 8.36×10?7 A. With the increase of pulse number, the corrosion potential increased while corrosion current on the sample surface, corrosion rate and corrosion tendency decreased, the corrosion resistance of the specimen surface was best after 50 times of pulse treatment. After HCPEB treatment, the surface microstructure is subject to phase transition, the surface smoothness and presence of uniform fine acicular martensite theoretically account for corrosion resistance improvement of 50BA steel. In order to improve the corrosion resistance of 50BA steel, pulse number should be controlled over 30 times, and the higher, the better.