This standard is applicable to the determination of chromium content in tungsten powder, tungsten bar, tungsten trioxide, tungstic acid and ammonium paratungstate. Measuring range: 0.0002~0.030%.
GB/T 4324.21-1984 history
2012GB/T 4324.21-2012 Methods for chemical analysis of tungsten.Part 21:Determination of chromium content.Inductively coupled plasma atomic emission spectrometry
1984GB/T 4324.21-1984 Methods for chemical analysis of tungsten--The diphenylcarbazide photometric method for the determination of chromium content