GB/T 4702.17-2016Chromium metal-Determination of oxygen, nitrogen and hydrogen content-Inert gas fusion thermal infrared detection method and conductivity method (English PDF)

1 Scope

This part of GB/T 4702 specifies the determination of oxygen content and hydrogen content by infrared method and the determination of nitrogen content by thermal conductivity method.

This part is applicable to the determination of oxygen content, nitrogen content and hydrogen content in metallic chromium. Determination of oxygen content (mass fraction). 0.010% ~

0.800%; nitrogen content of the determination of the range (mass fraction). 0.001% to 0.070%; hydrogen content of the determination of the range (mass fraction). 0.001%

0.050%.

2 normative reference documents

The following documents are indispensable for the application of this document. For dated references, only the dated edition applies to this article

Pieces. For undated references, the latest edition (including all modifications) applies to this document.

GB/T 4010 Ferroalloy chemical analysis of the sample to take and preparation

GB/T 6682 Analytical laboratory water specifications and test methods

3 principle

The sample and the flux (nickel) were melted in a graphite crucible under an inert gas (He or Ar) in a pulsed electrode furnace to release oxygen

Gas, nitrogen, hydrogen. Oxygen and carbon to produce carbon monoxide or carbon dioxide, through the rare earth copper oxide after the carbon monoxide into dioxy

The carbon is charged by an inert gas into the carbon dioxide infrared detector, producing an electrical signal and with a known oxygen content of the metal chromium reference material

After the comparison of the electrical signal, so as to determine the oxygen content; and hydrogen through the rare earth copper oxide, the formation of water vapor, through the water infrared detector, lost

The electrical signal of the effluent, compared with the known hydrogen reference material/sample, gives the hydrogen content; the mixture of water and carbon dioxide passes through the gas

The cleaning agent is absorbed and the remaining nitrogen is charged to the thermal conductivity detector with the inert carrier gas, the detector outputs the electrical signal, the reference substance with the known nitrogen content /

After comparing the electrical signals of the samples, the nitrogen content is obtained.

4 reagents and materials

Unless otherwise stated, only the confirmed analytical reagent is used in the analysis, and the water used is distilled or deionized or substantially pure water,

Shall comply with the provisions of GB/T 6682 three or more water.