为研究有机漆涂层的激光损伤机理，利用红外连续波激光，开展了真空低温环境下聚氨酯黑漆涂层的激光辐照实验，并进行了扫描电子显微镜(SEM)和X射线光电子能谱(XPS)分析，结合宏观现象、微观形貌分析对损伤等级进行了划分。结果表明，红外激光对聚氨酯黑漆的作用以热效应为主，损伤在宏观上表现为涂层色泽下降、颜色变化、烧蚀，微观上出现了裂纹和颗粒团聚；辐照升温使涂层组分和化学结构发生了改变，粘结剂聚氨酯中氨基甲酸酯基团的C-N键和O-C＝O双键在激光辐照加热下容易断裂，导致材料降解、碳化，烧蚀产生热解气体和可凝挥发物。

Polyurethane-based black paint is a kind of gloss and flat paint used for stray light shielding in optical imaging systems. Experiments of infrared laser irradiation effect on polyurethane-based black paint are carried out in a vacuum cryostat. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) are used to investigate the changes of the surface morphology, chemical composition and structure. The mechanism of interaction between laser and polyurethane-based black paint is studied. Based on macro phenomenon and micro-appearance analysis, the degree of damage is proposed. The experimental data and results of simultaneously differential scanning calorimetry-thermogravimetry (SDT) analysis indicate that damage is mainly caused by laser heating; the deposition of heat generated by laser changes color of the coating and leads to pyrogenation, carbonization and thermal ablation. The morphologies obtained from SEM show that surface of the coating is covered by many nondirectional fine cracks and the pigment particles agglomerate together after laser irradiation. XPS analysis for the surface of coating with and without laser irradiation reveals that laser irradiation changes the chemical composition and structure of the coating, and the C-N bonds and O-C＝O double bonds of binder are more easily cut off and destroyed.