脉冲激光除锈工艺研究

Process Parameter Study on the Removing Rust Using Pulsed Laser

采用波长为1．06μm的脉冲激光进行了除锈工艺研究。主要研究了激光扫描速度、脉冲重复频率、扫描方式、离焦量、扫描线间距等工艺参数对于锈层清除率的影响，最后获得了优化的工艺参数，并采用该参数除锈的样品与砂纸打磨样品进行了抗腐蚀性能和拉伸力学性能对比。研究结果表明：过高的扫描速度和脉冲重复频率，无法清除锈层；而过低的扫描速度和脉冲重复频率，虽然能够很好的除去样品的锈层，但是会对除锈后的表面造成二次氧化。离焦量和扫描线间距会影响相邻脉冲光斑的重叠程度，这两个参数也应该选择合适的组合，过大的重叠会引起二次氧化。采用慢、快扫描速度和低、高脉冲重复频率交替、多次扫描以及每次扫描旋转一定角度的方式更有利于去除船用钢板上的深厚的锈蚀。激光除锈后的船用钢材的抗腐蚀性能是用砂纸打磨的样品的2～3倍。

The effects of the processing parameters on de-rusting using pulsed Nd：YAG laser have been investigated in this paper. The effects of scanning speed, pulse repetition frequency, scan spacing, the defocus amount on laser de-rusting have been studied. The results show that the high scanning speed and pulse repetition frequency can＇t remove the rust effectively, but too low scanning speed and pulse repetition frequency induce secondary oxidation on the de-rusted surface. The defocus amount and scan spacing affect the overlapping degree of the adjacent pulse light spot. The combination of these two parameters also should be chosen appropriately. Otherwise, too much overlap may lead to secondary oxidation. It is effective to remove the deep rust on the ship steel by using the alternating scanning speed and pulse repetition frequency, the multiple scanning and the method of rotating an angle each time. The corrosion resistance of the sample of laser de-rusting is 2 to 3 times better than that polished with sand paper.