This standard specifies the method for the determination of iron content in tantalum and niobium. This standard applies to the determination of iron content in tantalum and niobium, and also applies to the determination of iron content in their hydroxides. The measurement range is >0.02% to 0.3%.
GB/T 15076.4-1994 history
2020GB/T 15076.4-2020 Methods for chemical analysis of tantalum and niobium—Part 4:Determination of iron content—1,10-Phenanthroline spectrophotometry
1994GB/T 15076.4-1994 Methods for chemical analysis of tantalum and niobium-Determination of iron content