ISO 3980:1977 pdf download.Aluminium and aluminium alloys - Determination of copper - tomic absorption spectrophotometric method
1 SCOPE
This International Standard specifies a method for the determination of copper in aluminium and its alloys by atomic absorption spectrophotometry.
2 FIELD OF APPLICATION
This method is applicable to copper (Cu) contents between 0,005 and 5 % (m/m).
3 PRINCIPLE
Dissolution of a test portion with hydrochloric acid and hydrogen peroxide. Atomization of this solution into an air-acetylene (or nitrous oxide-acetylene) flame of the atomic absorption apparatus. Comparison of the absorp-tion of the resonance energy of copper (wavelength nor-mally 324,7 nm) with that of calibration solutions.
4.6 Aluminium, 20 g/l base solution.
Weigh, to the nearest 0,01 g, 20 g of aluminium free from copper (purity ≥ 99,99 %) previously pickled; transfer it to a 1 000 ml beaker (for example) and cover. Add, in small portions, 600 ml of the hydrochloric acid solution (4.1) and if necessary a drop of metallic mercury to facilitate the attack. If necessary, warm gently to assist the dissolution;then add some drops of the hydrogen peroxide solution (4.2)，and boil some minutes to remove the excess of hydrogen peroxide.
After cooling, transfer the solution thus obtained quanti-tatively to a 1 000 ml volumetric flask; make up to volume and mix.
50 ml of this solution contains 1 g of aluminium and 30 ml of hydrochloric acid solution (4.1).
5 ml of this solution contains 0,1 g of aluminium and 3 ml of hydrochloric acid solution (4.1).
2 ml of this solution contains 0,049 of aluminium and 1,2 ml of hydrochloric acid solution (4.1).
7.2.1.1 COPPER CONTENTS BETWEEN 0,005 AND 0,05%
To a series of seven 100 ml volumetric flasks transfer the volumes of the standard copper solutions (4.7 and 4.8) shown in table 1, using the burette (5.1). Add to each flask 50 ml of the aluminium solution (4.6); make up to volume and mix.
7.2.1.2 COPPER CONTENTS BETWEEN 0,05 AND 0,5%
To a series of seven 100 ml volumetric flasks transfer the volumes of the standard copper solutions (4.7 and 4.8),shown in table 2, using the burette (5.1). Add to each flask 5 ml of the aluminium solution (4.6), make up to volume and mix.
7.2.1.3 CoPPER CONTENTS BETWEEN 0,5 AND 5%
To a series of seven 100 ml volumetric flasks transfer the volumes of the standard copper solution (4.7) shown in table 3, using the burette (5.1). Add to each flask 2 ml of the aluminium solution (4.6), make up to volume and mix.
7.3.1 Preparation of the test solution Transfer the test portion (7.1) to a 250 ml beaker (for example) and cover. Add about 30 to 40 ml of water, then,in small portions, 30 ml of the hydrochloric acid solution (4.1), heating gently, if necessary, to complete the dissol-ution. Add some drops of the hydrogen peroxide solution (4.2) and heat for about 10 min to remove the excess of hydrogen peroxide. Filter if necessary.ISO 3980 pdf download.