基于LIBS及时间分辨特征峰的激光除漆机理研究

摘要

激光除漆是一种高效、清洁的新型清洗技术,对激光除漆物理过程和机理的研究是该技术发展的关键.基于LIBS技术,测量得到油漆去除过程中等离子体的发光光谱,计算出油漆样品去除前后等离子体的电子密度和温度,研究了油漆中特征元素对应的光谱特征峰强度随时间的变化情况.结果表明,随着激光作用脉冲数量的增加,油漆去除深度逐渐增加,等离子体电子密度和温度在将漆去除干净的最后几个脉冲作用时呈下降趋势.油漆中Ti元素的所对应的特征峰信号持续时间为2个μs,油漆去除前后信号强度呈现跳跃减少,该现象可用于快速、准确、实时的判断油漆去除情况.%Laser paint stripping is an effective,clean and novel technology.The key for promoting the applications of this technology is to study the mechanisms involved in the process of laser paint removal.Based on the laser-induced breakdown spectroscopy(LIBS),we measured the plasma spectrum versus the irradiated pulse numbers.The electron density and tempera-ture were calculated.Time resolved intensity of the spectrum peak,which corresponded to the characteristic element in the paint,was carried out.The results showed that the paint were stripped progressively as the number of the pulse increasing.The electron density and temperature decreased when the paint was removed.The signal corresponded to Ti lasts for several μs.It changed dramatically before and after the paint removal,which can be used to as a fast,accurate and online way to determine whether the paint has been clean out.