A Fundamental Study on the High-Power Fiber Laser Cleaning for Removing the Multi-Layer Coating

The mechanical cleaning technology used in existing coating removal processes, such as blasting and grinding, has various problems, including environmental pollution owing to fine dust, worker welfare problems, and increased process time. As an alternative, an eco-friendly laser cleaning technology has attracted attention. However, research on high-power laser cleaning technology for removing thick coating layers and repairing large areas is limited. In this study, a high-power fiber laser with an average power of 1 kW was used to conduct cleaning experiments to remove a the multi-layer coating with a thickness of approximately 340 ㎛; this coaing is applied to improve the corrosion resistance of steel used for shipbuilding. As a result of experiments based on the main process parameters, such as energy density, average power, and beam mode, the cleaning performance can be significantly improved under a high power density. Moreover, because it exhibits a large difference in surface roughness controllability for each beam mode, it is estimated that the utilization of laser cleaning technology can be maximized depending on the application part. Key words: High-power laser cleaning process, Eco-friendly technology, Multi-layer coating