This standard applies to the determination of phosphorus content in silicon-chromium alloys, with a determination range of 0.010% to 0.060%.
GB/T 4699.3-1984 history
2007GB/T 4699.3-2007 Ferrochromium, silicochromium and nitrogen-bearing ferrochromium.Determination of phosphorus content.Molybdobismuthylphosphoric blue speckophotometric method and the molybdenum blue spectrophotometric method
1984GB/T 4699.3-1984 Methods for chemical analysis of silicochromium--The molybdenum blue photometric method for the determination of phosphorus content