三波长皮秒激光清洗石质文物的对比研究  

Comparative Study on Laser Cleaning of Stone Relics at Three Different Wavelengths

作　　者：胡文哲 宋官印 李晨毓 张雪雁[3,4] 聂树真 曲亮 刘晓龙[1,2,4] Hu Wenzhe;Song Guanyin;Li Chenyu;Zhang Xueyan;Nie Shuzhen;Qu Liang;Liu Xiaolong(Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,China;School of Optoelectronics,University of Chinese Academy ofSciences,Beijing 100049,China;Conservation Standards Research Institute,the Palace Museum,Beijing 100009,China;China-Greece Belt and Road Joint Laboratory on Cultural HeritageConservation Technology,Beijing 100009,China)

机构地区：[1]中国科学院空天信息创新研究院,北京100094 [2]中国科学院大学光电学院,北京100049 [3]故宫博物院文物保护标准化研究所,北京100009 [4]中国-希腊文物保护技术“一带一路”联合实验室,北京100009

出　　处：《中国激光》2024年第20期66-74,共9页Chinese Journal of Lasers

基　　金：国家重点研发计划(2020YFE0204600);中国科学院青年创新促进会(2021123)。

摘　　要：针对安全高效地清除石质文物表面污染物的需求,进行1064、532、355 nm三个波长皮秒激光清洗自制石质文物样品的数值模拟和实验的对比研究。使用双温模型模拟三个波长皮秒激光与污染物相互作用的过程和其与同能量密度激光烧蚀深度的差异,通过实验确定石质文物表面污染物在三个波长皮秒激光作用下的清洗阈值,并从清洗阈值、清洗效率、粗糙度、元素含量等多方面对比分析了三个波长皮秒激光清洗效果的差异。实验中使用共轴电荷耦合器件(CCD)实时监测系统以控制激光清洗的进程,使用共聚焦显微镜和荧光能谱仪分别测量清洗后石质文物的表面粗糙度和元素含量。实验结果表明,三个波长皮秒激光的清洗阈值分别为0.198±0.033、0.573±0.114和(0.739±0.249)J/cm^(2)。能量密度为2 J/cm^(2)时,三个波长的激光烧蚀污染层深度分别为171、106、62μm,且1064 nm波长的激光清洗后的样品表面粗糙度最小,污染物的主要成分硫元素(S)和铁元素(Fe)的含量最低。综合考虑清洗阈值、清洗效率、清洗后样品表面粗糙度、污染物元素含量等多方面,1064 nm波长的激光清洗阈值最低,清洗效率最高,清洗得最为彻底,整体清洗效果优于另外两个波长激光。Objective Cultural relics suffer from corrosion and damage caused by the fragile composition of the material and the surface pollutants resulting from environmental changes.Laser cleaning,characterized by high efficiency,environmental friendliness,and strong controllability,is an effective method for removing surface pollutants without harming the relics,rendering it suitable for cleaning various types of cultural relics.Recognizing the advantages of ultrashort pulse lasers in the realm of cultural relic cleaning,along with the critical role of the laser wavelength in this process,two primary research focuses have emerged:picosecond and multiwavelength laser cleaning of cultural relics.This paper addresses the requirements for applying laser cleaning to stone cultural relics.Comprehensive numerical simulations and experiments were conducted on the removal of surface contaminants using picosecond lasers at wavelengths 1064,532,and 355 nm.Concurrently,a variety of real-time and offline detection methods were employed in a coordinated manner to analyze the effects of picosecond laser cleaning at these three wavelengths,considering aspects such as sample surface morphology,roughness,and elemental content.The ultimate goal was to determine the most suitable wavelength parameters for cleaning stone cultural relics.Methods To address the specific demands for laser cleaning of stone cultural relics,in this study,a systematic investigation is conducted through numerical simulations and experimental research on the surface pollutants of stone cultural relics treated with a picosecond laser at three wavelengths:1064,532,and 355 nm.A two-temperature model is applied to simulate the interaction between picosecond laser pulses of the three wavelengths and surface contaminants,considering differences in the ablation process and depth at the same laser energy density.Building on this foundation,the damage threshold of the picosecond laser at three wavelengths and the cleaning thresholds for surface pollutants on stone cultural r

关 键 词：激光清洗 石质文物 三波长皮秒激光 双温模型 清洗阈值 

分 类 号：TN249[电子电信—物理电子学]