以硫酸钾基准试剂绘制校准曲线,将试样置于铺有0.50 g纯铁的瓷坩埚中,再覆盖3.0 g 纯钨,建立了高频燃烧红外线吸收法测定锡铅焊料中痕量硫的方法.确定最佳实验条件如下:硫质量分数不大于0.001 0%时,试样量为1.0 g;硫质量分数为0.001 0%~0.010%时,试样量为0.50 g;硫质量分数为0.010%~0.025%时,试样量为0.20 g.结果表明,硫量在0.001 0~0.050 mg之间与其吸光度呈良好的线性关系,相关系数r=0.999 7.方法检出限为0.000 021%,测定下限为 0.000 084%.对选定的4个不同硫含量水平的锡铅焊料内控样品进行11次平行测定,测定结果与参考值基本一致,相对标准偏差(RSD)在7.3%~15.0%之间,回收率在96%~115%之间.硫质量分数在0.000 10%~0.025%之间,方法的重复性标准偏差为Sr=0.064 6 x+0.000 01、重复性限为r=0.181 2 x+0.000 03,再现性标准偏差为SR=0.081 9 x-0.000 002、再现性限为R=0.229 7 x-0.000 006.%The calibration curve was prepared by standard reagent of potassium sulfate.The sample was placed onto porcelain crucible containing 0.50 g of pure iron followed by covering 3.0 g of pure tungsten.The determination method of trace sulfur in tin-lead solder by high frequency combustion infrared absorption method was established.The optimal experimental conditions obtained were listed as below: the sample mass was 1.0 g when S≤0.001 0%;the sample mass was 0.50 g when 0.001 0%展开▼
