金属表面腐蚀层及涂层的激光干式清洗研究进展

Research Progress in Dry Laser Cleaning on Corrosion and Coating Layers of Metal Surfaces

激光干式清洗方法,因操作简单、清洗过程易于控制等优点,目前应用最为广泛。重点介绍了激光干式清洗在各种金属材质表面不同腐蚀层和涂层清除中的应用,包括有多种钢材表面的锈层,钢材表面的ZrO2、Cr2O3、Al2O3变性层,热轧钢表面高温氧化层,Ti合金表面富氧α相层,合金钢在H2S环境中腐蚀而形成的硫化层,钢、铝合金、钛合金表面漆层,热压成型钢板表面Al-Si涂层以及航空压缩机Ti合金叶片TiAlN涂层等。分类对比了不同清洗对象所需选用的合适激光清洗工艺参数,如波长、脉宽、频率、功率、扫描速率等。金属材料激光干式清洗多选用波长为1064 nm的纳秒激光器,清洗后表面粗糙度可达1μm,且随着能量输入的升高而增大。锈层的去除主要依靠高温烧蚀作用,变性层是由于产生的热弹性应力而剥离,而漆层和涂层则是由于烧蚀气化、热振动、热冲击等机制实现清洗。最后,对激光清洗技术在国内不同工业领域中的应用前景进行了展望。

The development and classification of laser cleaning technology were briefly stated.The dry laser cleaning is widely used so far by virtue of its superiority of easy operation and control.The application of dry laser cleaning in different corrosion and coating layer removal of various metal materials was summarized,including the rust and degeneration lays of ZrO2、Cr2O3、Al2O3 on steel surfaces,the high temperature on hot rolled steel surface,the oxygen-enriched alpha case layer on titanium alloy surface,the sulfide scale on alloy steel surface formed by corrosion in H2S atmosphere,the coats of painting on steel,aluminum and titanium alloy surfaces,the Al-Si coating on hot-press-forming(HPF)steel sheet surfaces and the TiAlN coating on titanium alloy blades of aviation compressor.The different laser cleaning parameters,such as wavelength,pulse width,frequency,power,and scanning rate,are required for different cleaning objects.The nanosecond laser with a wavelength of 1064 nm was generally used for dry laser cleaning of metal materials.The surface roughness after cleaning reached to 1μm and increased with increasing energy input.The removal of rust layers mainly depended on the high temperature ablation.The degeneration layers were peeled off by the thermos-elastic stress action.The painting and the coating layers were cleaned by high temperature ablation gasification,thermal vibration,thermal shock etc.Additionally,the application directions of laser cleaning technology in different industrial fields in China are prospected.