X射线荧光光谱法测定锡钢板71型钝化膜厚度  

Determination of passive film thickness of tin plate type 71 by X-ray fluorescence spectrometry

作　　者：刘洋 朱启茂 何小琴 姚远 陈梦乔 LIU Yang;ZHU Qimao;HE Xiaoqin;YAO Yuan;CHEN Mengqiao(Quality Inspection and Supervision Department,Shougang Jingtang United Iron&.Steel Co.,Ltd.,Tangshan 063200,China)

机构地区：[1]首钢京唐钢铁联合有限责任公司质检监督部,河北唐山063200

出　　处：《冶金分析》2024年第8期67-71,共5页Metallurgical Analysis

摘　　要：镀锡板71型钝化膜的厚度与产品质量和性能密切相关,其准确测定具有重要意义。选取7块不同厚度梯度的71型钝化膜镀锡板样品,参照GB/T 1838中的卫星取样法进行取样,采用GB/T 28290中分光光度法进行定值,作为校准样品系列绘制校准曲线,实现了X射线荧光光谱法(XRF)对镀锡板71型钝化膜厚度的测定。由于71型钝化膜中存在氧化铬、氢氧化铬、金属铬等多种形态,并且金属铬含量的多少与氧化铬层随时间变化对钝化膜校准样品的储存与定值会产生严重影响,进而影响校准曲线的准确性。试验对快速固化稳定钝化层的方法进行讨论,用极化曲线对表面钝化膜的耐蚀进行研究表明,在200℃烘烤15 min,腐蚀电流密度最低,镀锡板的耐蚀性最好。用钝化膜厚为4.26 g/m^(2)的校准样品2#分别进行短期稳定性和长期稳定性测试,结果表明,短期和长期稳定性试验测定结果的相对标准偏差(RSD,n=10)分别为1.2%和2.0%,所得结果符合GB/T 27417中实验室内RSD小于5.3%的规定。取6个71型钝化膜镀锡板样品,分别使用本法和GB/T 28290中分光光度法进行分析,结果表明:本法测定值与分光光度法测定值基本一致,经计算得到统计量P=0.817 5,可知两组数据之间不存在显著差异。The passive film thickness of tin plate type 71 is closely related to the product quality and proper-ty,so its accurate determination is of great significance.Seven pieces of tin plate type 71 samples with dif-ferent passive film thickness gradient were selected and sampled according to the satellite sampling method in GB/T 1838.The spectrophotometry in GB/T 28290 was adopted for quantification.These samples were used as calibration sample series for the preparation of calibration curve.The determination of passive film thickness of tin plate type 71 by X-ray fluorescence spectrometry(XRF)was realized.Since the passive film type 71 contained various forms such as chromium oxide,chromium hydroxide and chromium metal,and the storage and quantification of passive film standard sample could be seriously affected by the content of chromium metal and the variation of chromium oxide layer with time,the accuracy of calibration curve would be influenced.The methods for rapid stabilization of passive layer were discussed in experiments.The corrosion resistance of surface passive film was investigated using polarization curve.The results indi-cated that when it was heated at 20o C for 15 min,the corrosion current density was lowest,and the cor-rosion resistance of tin plate was best.The calibration sample 2#with passive film thickness of 4.26 g/m?was used for short-term stability and long-term stability tests.The results showed that the relative stand-ard deviation(RSD,n=1o)of determination results of short-term stability and long-term stability tests was 1.2%and 2.0%,respectively,which could meet the requirement of intra-laboratory RSD less than 5.3%in GB/T 27417.Six samples of passive film tin plate type 71 were selected and analyzed according to the experimental method and spectrophotometry in GB/T 28290.The results showed that the found re-sults of this method were basically consistent with those obtained by spectrophotometry.The statistical magnitude P=0.8175 was obtained through calculation,indicating that there was n

关 键 词：镀锡板 71型钝化膜 X射线荧光光谱法(XRF) 厚度 

分 类 号：O657.34[理学—分析化学] TF031[理学—化学]