GB/T 15076.14-2008Methods for chemical analysis of tantalum and niobium - Determination of oxygen content (English PDF)

Foreword

GB/T 15076 Methods for chemical analysis of tantalum and niobium is divided into 16 parts:

-- GB/T 15076.1 Methods for chemical analysis of tantalum and niobium - Part 1: Determination of tantalum content in niobium - Inductively coupled plasma atomic emission spectrometry -- GB/T 15076.2 Methods for chemical analysis of tantalum and niobium - Part 2: Determination of niobium content in tantalum - Inductively coupled plasma atomic emission spectrometry and stratigraphy gravimetry -- GB/T 15076.3 Methods for chemical analysis of tantalum and niobium - Part 3: Determination of copper content - Flame atomic absorption spectrometry -- GB/T 15076.4 Methods for chemical analysis of tantalum and niobium - Part 4: Determination of iron content - 1,10-Phenanthroline spectrophotometry -- GB/T 15076.5 Methods for chemical analysis of tantalum and niobium - Part 5: Determination of molybdenum and tungsten contents - Inductively coupled plasma atomic emission spectrometry -- GB/T 15076.6 Methods for chemical analysis of tantalum and niobium - Part 6: Determination of silicon content - Inductively coupled plasma atomic emission spectrometry -- GB/T 15076.7 Methods for chemical analysis of tantalum and niobium - Part 7: Determination of phosphorus content in niobium - 4-Formyloxy-pentyl ketone- [2] extraction separation phosphomolybdate blue spectrophotometry and inductively coupled plasma atomic emission spectrum -- GB/T 15076.8 Methods for chemical analysis of tantalum and niobium - Determination of carbon and sulphur contents -- GB/T 15076.9 Methods for chemical analysis of tantalum and niobium - Determination of iron, chromium, nickel, manganese, titanium, aluminum, copper, tin, lead and zirconium contents in tantalum -- GB/T 15076.10 Methods for chemical analysis of tantalum and niobium - Part 10: Determination of iron, nickel, chromium, titanium, zirconium, aluminum and manganese contents in niobium - Direct current arc atomic emission spectrometry Methods for chemical analysis of tantalum and niobium - Determination of oxygen content

1 Scope

This part specifies the method for determining the oxygen content in tantalum and niobium.

This part is applicable to the determination of oxygen content in tantalum and niobium. Determination range: 0.005%~1.2%.

2 Principle of the method

The test specimen is placed in a high-purity graphite crucible under a purified helium/argon atmosphere, and melted at a high temperature with a low voltage and a large current, and the oxygen compounds are reduced and decomposed. The oxygen released from the sample combines with the carbon in the graphite crucible to form a mixture of carbon monoxide and carbon dioxide. The carbon monoxide is converted into carbon dioxide by rare earth copper oxide, and the generated carbon dioxide is detected in an infrared cell.

3 Materials

3.1 Helium: with a purity of greater than 99.99%.

3.2 Argon: with a purity of greater than 99.99%.

3.3 High-purity nickel foil or nickel capsule: the oxygen content is not more than 0.002%.

3.4 High-purity graphite crucible.

3.5 Standard substances: Appropriate standard substances shall be selected. In principle, the chemical composition of the standard substances shall be similar to that of the analyzed samples.

4 Instruments

Pulse infrared oxygen analyzer: The instrument sensitivity is not less than 0.01 µg/g. […]