镀锡板镀层的辉光放电光谱法解析

Analysis of tinplate layer by glow discharge spectrometry

利用辉光放电光谱法对镀锡板样品进行逐层剥离,根据样品由表至里的辉光放电积分图谱,分别设定公式积分计算镀锡板镀层厚度及质量、钝化层厚度及质量、基板成分、镀层中有害元素等。采用辉光放电光谱对镀锡板做深度-时间图,可知镀锡层的深度分辨率低于基板铁层。将方法应用于测定镀层质量、钝化层质量、基板成分(碳、硅、锰、磷、硫、镍、铬和铜)的测定,相对标准偏差分别不大于2.3%(n=10)、3.0%(n=10)、4.3%(n=5),分别将实验方法测定结果与X射线荧光光谱法(XRF)、光度法、电感耦合等离子体原子发射光谱法(ICPAES)进行比对,结果基本一致。采用实验方法对镀锡板镀层中的有害元素进行了测定,可实现镀锡板多个检测项目的同时测定。

When tinplate sample was ablated layer by layer by glow discharge spectrometry（GDS）, formula integral was set according to glow discharge integral spectrum from sample surface to its center for the purpose of calculating the thickness and mass of tinplate coating and passivation layer, substrate component, harmful elements in the coating, etc. The depth-time diagram was curved by GDS, and it showed that the depth resolution of tin coating was lower than that of substrate iron layer. The method has been applied to determine the mass of tinplate coating and passivation layer, substrate component（carbon, sili- con,manganese, phosphorus, sulfur, nickel, chromium and copper）, and the relative standard deviation was not higher than 2.3% （n = 10） ,3.0% （n = 10） and 4.3% （n = 5）. The results were consist with those obtained by X-ray fluorescence spectrometry （XRF）, spectrophotometry and inductively coupled plasma atomic emission spectrometry（ICP-AES）. The harmful elements in the tinplate coating were deter- mined by this method. The method could realize the simultaneous determination of multi testing items in tin plate.