GB/T 223.37-1989 Methods for chemical analysis of iron,steel and alloy--The indophenol blue photometric methods for the determination of nitrogen content after distillation separation (English Version)
This standard specifies the determination of nitrogen content by distillation separation-indophenol blue photometry. This standard is applicable to the determination of nitrogen content in pure iron, carbon steel, alloy steel, superalloy and precision alloy, but not applicable to the determination of nitrogen content in silicon steel and its profiles smelted without adding aluminum. Measuring range: 0.0010% to 0.050%.
GB/T 223.37-1989 history
2020GB/T 223.37-2020 Iron, steel and alloy—Determination of nitrogen content—Indophenol blue spectrophotometric method after distillation separation
1989GB/T 223.37-1989 Methods for chemical analysis of iron,steel and alloy--The indophenol blue photometric methods for the determination of nitrogen content after distillation separation
1985GB 223.37-1985 Methods for chemical analysis of iron, steel and alloys Distillation separation-volumetric determination of nitrogen content
GB/T 223.37-1989 Methods for chemical analysis of iron,steel and alloy--The indophenol blue photometric methods for the determination of nitrogen content after distillation separation has been changed from GB 223.37-1985 Methods for chemical analysis of iron, steel and alloys Distillation separation-volumetric determination of nitrogen content.