scope:

This Standard specifies the infrared absorption method after combustion among the determination methods of carbon content of iron and steel. This method is applicable to the determination of carbon content (mass fraction) in iron and steel in the range of 0.001% or over to and including 5.0 %. When using the working curve of reagent or reference solution, it is applicable to the determination in the range of 0.003 % or over to and including 4.5 % in mass fraction.

NOTE 1 When the carbon content is determined according to the method specified in this Standard, there is the possibility that the higher value than the carbon content of the test portion itself is reported because the carbon adhered or adsorbed to the surface of the test portion may be determined together. However, the difference is usually about 0.000 2 % in mass fraction and less than 0.000 5% at most. For the method of determination excluding the influence of the carbon adhered or adsorbed to the surface of the test portion in the determination of carbon in micro range, JIS G 1211-4 is specified. In case of doubt in the analytical value of 0.001 % to 0.010 % in carbon content (mass fraction), it is recommended that the analytical value according to JIS G 11211-4 be adopted.

NOTE 2 The International Standards corresponding to this Standard and the symbol of degree of correspondence are as follows:

ISO 9556: 1989 Steel and iron-Determination of total carbon content-Infrared absorption method after combustion in an induction furnace

ISO 15350: 2000 Steel and iron-Determination of total carbon and sulfur content-Infrared absorption method after combustion in an induction furnace (routine method) (overall evaluation: MOD)

The symbols which denote the degree of correspondence in the contents between the relevant International Standard and JIS are IDT (identical), MOD (modified), and NEQ (not equivalent) according to ISO/lEC Guide 21-1.