以TiO2 为颜料, 硅酸钾为粘结剂(以下简称KS-T), 采用空气喷涂的方法, 在铝基底上制备了一种抗激光烧蚀涂层。研究了粉体粒径大小、固含量、涂层厚度等因素对涂层反射率的影响, 获得了1064 nm 激光波段下反射率达到96.8%的KS-T 涂层。基于热传导方程建立三维有限元模型模拟材料的瞬态温度场分布, 测量激光辐照过程中铝基底的背底温度变化, 与模拟结果相比较, 发现KS-T 涂层可以有效地保护基底不被激光烧蚀。模拟结果显示, 在辐照一段时间后, 样品的反射率出现了下降的现象, 分析了反射率下降的可能原因；计算结果还表明考虑界面热阻(ITR)后,涂层/基底界面处出现一个明显的温降, 阻止热流向基底的传输, 从而使铝基底保持一个较低的温度。

An anti-laser-ablation coating using TiO2 as pigment and potassium silicate as binder (abbreviated as KS-T) was deposited on the aluminum alloy substrate by an air spray process. Factors influencing the reflectance of KS-T coating, including particle size, pigment volume concentration and coating thickness, were investigated. The reflectance of prepared KS-T coating could be up to 96.8% at the laser wavelength of 1064 nm. A three-dimensional finite element model based on the heat-conduction equation was developed to simulate the distribution of transient temperature filed. By monitoring the temperature variation at the backside center of aluminum alloy substrate during laser irradiation and comparing with the simulation results, it is found that KS-T coating could effectively protect the substrate from laser ablation. The simulation results demonstrated reflectance decrease of samples after a period of irradiation. The possible reasons for the reflectance decrease were proposed. The calculation results also showed that an obvious temperature drop emerged at the coating/substrate interface when interface thermal resistance (ITR) was considered. Eventually heat flux was prevented from flowing to the substrate and aluminum alloy kept a low temperature.