铜钢复合材料覆层金属锌含量的测定

研究了不同比例过硫酸铵氨水溶液溶解铜钢复合材料覆层金属的试验方法，确定用33 g过硫酸铵溶入500 mL氨水（1：1）中的覆层溶解液可以均匀溶解覆层金属，并对基体没有影响的试验方法.在覆层金属溶解后的液体中，pH为5~6时，以氟化钾、抗坏血酸掩蔽铁及其他杂质，以硫脲掩蔽铜，二甲酚橙为指示剂，乙二胺四乙酸二钠（EDTA-2Na）标准溶液滴定锌，滴定终点明显，效果较好.用该方法对铜钢复合材料进行精密度试验，RSD（n=11）在0.83%~1.58%，加标回收试验，加标回收率在97%~101%.建立了铜钢复合材料覆层金属锌含量测定的新方法，该方法操作简便，精密度高.

Determination on Zinc Content in Copper Steel Composite Coating

The ammonium persulfate ammonia solutions with different content were used to dissolve cladding metal on copper steel compound.It was found that the 33 g ammonium persulfate with 500 mL of liquid ammonia(1:1) is the optimal solution to uniformly dissolve cladding metal coating without affecting the substrate.The dissolved cladding solution with pH5-6, was titrated the zinc by ethylene diamine tetraacetic acid disodium salt(EDTA-2Na) standard solution along with xylenol orange as indicator, which shows very good results.Finally this method was used for precision test in copper steel composite, and the RSD(n=11) was between 0.83%-1.58%, and the standard addition recovery was between 97%-101%.It has been demonstrated that this method for the determination of zinc content in copper steel composite coating is valid for simple and high precise operation.