激光剥蚀电感耦合等离子体质谱法测定金属镀锡层的厚度  

Quick Measurement of Thickness of Tin Coating on Metal by Laser Ablation Inductively Coupled Plasma-Mass Spectrometry

作　　者：金献忠 谢健梅 陈建国 

机构地区：[1]宁波检验检疫科学技术研究院,浙江宁波315012

出　　处：《岩矿测试》2015年第3期286-291,共6页Rock and Mineral Analysis

基　　金：国家质检总局科技计划项目(2013IK010;2012IK043)

摘　　要：激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)应用于测定金属镀锡层的厚度时激光脉冲能量的大小及其稳定性会影响分析结果的准确度。本文采用一款自制的皮秒激光剥蚀固体进样系统(ps LA),与ICP-MS联用建立了一种测定金属镀锡层厚度的方法。在激光脉冲能量为12μJ,散焦距离为625μm的条件下采集锡和镀锡层基材元素检测同位素的时间分辨图,根据提出的边界确定规则确定了剥蚀镀锡层的时间,同时根据厚度标准片计算单位脉冲剥蚀量。该方法的单位脉冲剥蚀量为88 nm/pulse,厚度分辨率为0.40μm,应用于测定钢镀锡厚度标准片、铜镀锡厚度标准片、有涂层马口铁和镀锡不锈钢带等样品,测定值与认定值的最大偏差为0.5μm。本方法避免了激光脉冲能量的不稳定使得单位脉冲剥蚀量发生变化的问题,提高了镀层厚度测定的准确度,适用于各种形态、各种规格金属镀层厚度的测定,也可应用于生命科学、考古、环境、司法等领域。Thickness analysis of tin coating on metal by Laser Ablation Inductively Coupled Plasma-Mass Spectrometry（ LA-ICP-MS） is affected by the laser pulse energy and its stability. A method has been proposed for quick measurement of thickness of tin coating on metal using a self-made picosecond laser ablation system coupled Inductively Coupled Plasma-Mass Spectrometry. Laser ablation was carried out using pulse energy of 12 μJ and defocus distance of 625 μm. Time resolved spectra（ TRS） of118 Sn and measured isotopes of the main elements in substrate were acquired,the time of ablation of zinc coating was gained according to the relationship of these TRS,the ablation rate was calculated by thickness standard sheet,and thickness of tin coating could be measured quickly. Ablation rate of tin coating was 88 nm / pulse and depth solution was 0. 40 μm. The thickness standard sheet and practical sample,including tinplate with paint coating and tinned stainless steel strip,were analyzed by this method. The maximum deviation between the found values and the certified values was 0. 5 μm. This method avoids the instability of ablation rate which results in the change of ablation amounts of one pulse. This method improves the accuracy and is suitable for the thickness measurement of metal coating of different types,and could be used in fields such as life sciences,archaeology,environment,and judicial expertise.

关 键 词：镀锡层 涂层 厚度 皮秒激光剥蚀(psLA) 电感耦合等离子体质谱法 

分 类 号：O657.63[理学—分析化学]