为了研究激光除锈工艺应用于高速列车集电环的可行性, 根据激光除锈效果和清洗效率, 确定了集电环的最优激光清洗参量, 即在激光覆盖试样整个表面的光斑搭接率为29.3%时,激光功率为16W, 激光重复频率为70kHz, 激光扫描速率为1.0m/s。采用最优工艺参量对集电环试样进行激光除锈, 通过扫描电镜和金相显微镜观察原始试样和激光除锈后试样的表面微观组织; 采用新的实验分析手段分析对比原始试样和激光除锈后试样表面硬度和表面力学性能; 室温条件下采用LINSES电阻率测试仪对激光清洗前后试样的电阻率进行测量。结果表明, 激光除锈后试样表面没有发生重熔和相变; 原始试样和激光除锈后试样表面硬度和表面力学性能对比没有发生明显变化; 由于表面粗糙度的增加以及部分晶体点阵发生的晶格畸变, 增加了电子散射的几率, 使电阻率提高8.3%, 但仍符合使用规范。激光除锈技术对集电环基底表面性能没有产生显著影响, 该工艺适用于高速列车集电环表面除锈。

In order to study the feasibility of applying laser technology to remove rust from collector rings of high-speed train, according to the effect of laser rust removal and cleaning efficiency, the optimal laser cleaning parameters of collector ring were determined. Overlap ratio of laser spot on the whole surface is 29.3%, laser power was 16W, laser repetition frequency was 70kHz and laser scanning speed was 1.0m/s. The optimal process parameters were used to remove rust from the collector ring samples. The surface microstructure of the original sample and the sample after laser rust removal were observed by scanning electron microscope and metallographic microscope. The surface hardness and surface mechanical properties of the original sample and the sample after laser rust removal were analyzed and compared by a new experimental analysis method. The resistivity of samples before and after laser cleaning was measured by LINSES resistivity tester at room temperature. The results show that there is no remelting and phase transformation on the surface of samples after laser derusting. The surface hardness and surface mechanical properties of the original sample and the laser rust removal sample don’t change significantly. Due to the increase of surface roughness and lattice distortion of some crystal lattice, the probability of electron scattering increases and resistivity increases by 8.3%. But they still conform to the specifications. Laser derusting technology has no significant effect on the surface performance of collector ring substrate. The technology is suitable for surface rust removal on the collector rings of high-speed trains.