GOST 1762.5-71
GOST 1762.5−71 Silumin ingots. Methods for determination of manganese (with Amendments No. 1, 2)
GOST 1762.5−71
Group B59
STATE STANDARD OF THE USSR
SILUMIN IN PIGS
Methods for determination of manganese
Aluminium-silicon alloy ingots.
Methods for determination of manganes
AXTU 1709
Valid from 01.01.73
to 01.07.95*
_______________________________
* Expiration removed
Protocol N 4−93 inter-state Council
for standardization, Metrology and certification.
(IUS N 4, 1994). — Note the CODE.
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
THE DEVELOPERS OF THE STANDARD
A. A. Kostyukov, G. A. Romanov, N. M. Gertseva, A. P. Nechitailov, V. A. Lavrov
2. APPROVED AND promulgated by the Decree of the State Committee of standards of Ministerial Council of the USSR from
3. The frequency of inspection — 5 years
4. REPLACE GOST 1762−51 (in terms of sec. VI)
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced | Item number | |
| GOST 83−79 | Sec. 5 | |
| GOST 1762.0−71 | 1.1 | |
| GOST 2603−79 | Sec. 2 | |
| GOST 3118−77 | Sec. 5 | |
| GOST 4038−79 | Sec. 5 | |
| GOST 4197−74 | Sec. 2 | |
| GOST 4204−77 | Sec. 2, 5 | |
| GOST 4233−77 | Sec. 5 | |
| GOST 4328−77 | Sec. 5 | |
| GOST 4461−77 | Sec. 2 | |
| GOST 5457−75 | Sec. 5 | |
| GOST 6008−82 | Sec. 2, 5 | |
| GOST 6552−80 | Sec. 2 | |
| GOST 9428−73 | Sec. 5 | |
| GOST 10929−76 | Sec. 2, 5 | |
| GOST 11069−74 | Sec. 5 | |
| GOST 20490−75 | Sec. 2, 5 | |
6. Validity extended until
7. The re-release (may 1989) with Amendments No. 1, 2 approved in August 1984, March 1989 (IUS 12−84, 6−89)
This standard sets the photometric and atomic absorption methods for the determination of manganese at a mass fraction of from 0.005 to 0.8 percent in silumin in pigs.
(Changed edition, Rev. N 2).
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 1762.0−71.
PHOTOMETRIC METHOD
The method is based on measuring optical density of a solution of manganese acid formed by oxidation of divalent manganese to pneumococcal hodnoceni potassium or sodium in an acidic environment.
(Changed edition, Rev. N 2).
2. APPARATUS, REAGENTS AND SOLUTIONS
Type photoelectrocolorimeter FEK-56M, PEC-60, KLF, spectrophotometer type SF-16, SF-26 or similar.
Water without reducing substances; prepared as follows: water, acidified with sulphuric acid (5 cmof sulphuric acid diluted 1:1, in 1 DM
of water), bring to a boil, add a few crystals of potassium jednolitego and boiled for 10 min.
Potassium ignominy (periodic) or sodium cognately.
Sulfuric acid GOST 4204−77, diluted 1:1.
Nitric acid GOST 4461−77.
A mixture of acids, is prepared as follows: to 550 cmof water is poured, with stirring, 200 cm
of sulphuric acid diluted 1:1 and 250 cm
of nitric acid.
Orthophosphoric acid according to GOST 6552−80, diluted 1:1.
Hydrogen peroxide according to GOST 10929−76, a solution with a mass fraction of 3%.
Sodium atomistically according to GOST 4197−74, a solution with a mass fraction of 2%.
Potassium permanganate according to GOST 20490−75.
Manganese metal in the form of chips according to GOST 6008−82*.
________________
* Valid GOST 6008−90, here and hereafter. — Note the CODE.
Acetone according to GOST 2603−79.
Manganese metal in the presence of the oxide layer is pre-cleaned: a few grams of metal was placed in a beaker with a capacity of 250 cm, add about 80 cm
of sulphuric acid diluted 1:1, and 100 cm
of water, stirred and after a few minutes, poured the solution.
The metal was washed two times with water, then with acetone, dried in a drying Cabinet at 100 °C for 2 min and cooled in a desiccator.
Standard solutions of manganese
Solution a, prepared as follows: 0,2877 g of potassium permanganate dissolved in water, add 20 cmof sulphuric acid diluted 1:1, heat, add dropwise hydrogen peroxide to bleaching and evaporated to release vapors of sulfuric acid. The residue after cooling is diluted with water, transferred into a volumetric flask with a capacity of 1 DM
, made up to the mark with water and stirred or 0,1000 g of manganese dissolved in a beaker with a capacity of 400 cm
under the watch glass 20 cm
of sulfuric acid solution with the addition of 100 cm
of water. The solution was boiled a few minutes, cooled, transferred to a measuring flask with volume capacity of 1000 cm
, made up to the mark with water and mix.
1 cmof solution A contains 0.1 mg of manganese.
Solution B is prepared before use as follows: 25 cmsolution And placed in a volumetric flask with a capacity of 250 cm
, made up to the mark with water and mix.
1 cmof a solution contains 0.01 mg of manganese.
(Changed edition, Rev. N 1, 2).
3. ANALYSIS
3.1. When the mass fraction of manganese, up to 0.04%
A portion of the silumin of 0.5−1.0 g were placed in a glass with a capacity of 250 cm, 45−60 cm, pour the
mixture of acids and evaporated to highlight the thick white vapour of sulphuric anhydride. After cooling, to the residue was added to 80−100 cm
of hot water and heated to dissolve the salts. The hot solution is filtered through a dense filter paper mass, collecting the filtrate in a conical flask with a capacity of 250 cm
. The filter cake is washed with hot water.
The filtrate is evaporated to about 45 cm. To the hot solution add 5 cm
of phosphoric acid, heated to boiling, and add 0.3 g of potassium periodate. The resulting solution was stirred to dissolve the potassium periodate, boiled for 5 min to detect the color and then placed the flask with the solution at 35−40 min on a sand bath. During heating and boiling water is added to maintain the original liquid volume. Chilled colored solution was transferred to volumetric flask with a capacity of 50 cm
, pre-washed by water, containing reductive substances, dilute this to the mark with water and mix. The optical density of test solution is measured on a photoelectrocolorimeter or spectrophotometer, given that a maximum of light absorption of solutions corresponds to the wavelength of 528 nm. Solution comparison is water.
After measuring the optical density of decolorized manganese acid using two or three drops of a solution of sodium nitrite, add it to the cell and again measure the optical density of the solution. The difference between the optical density of the colored solution and the optical density of the background represents the optical density of manganese acid.
The content of manganese is found by the calibration schedule, taking into account the amendment of the control of the experience
.
3.1.1. Preparation of the solution in the reference experiment
30 cmof the mixture of acids is placed in a beaker with a capacity of 250 cm
and evaporated to dryness, not proKLIMA. To the residue poured a small amount of hot water and mix, then pour the 30 cm
of the mixture of acids is heated to release the vapours of sulphuric anhydride, cooled, diluted with water to a volume of about 45 cm
, add 5 cm
of phosphoric acid and further analysis is carried out as specified in clause 3.1.
3.1.2. Construction of calibration curve
In seven conical flasks with a capacity of 250 cmflow consistently 0; 2,0; 4,0; 6,0; 8,0; 10,0; 12,0; 15,0; 20,0 cm
standard solution B, which corresponds to 0; 0,02; 0,04; 0,06; 0,08; 0,10; 0,12; 0,15; 0,20 mg of manganese, is added to 20 cm
of the mixture of acids, dilute with water to volume is approximately 45 cm
, add 5 cm
of phosphoric acid, heated to boiling, add 0.3 g of potassium periodate and further analyze as described in section 3.1.
As a solution comparison, use water.
According to the obtained values of optical density and known mass of manganese in the solution to build calibration curve.
3.2. When the mass fraction of manganese from 0.04% to 0.8%
A portion of the silumin weighing 0.5 g were placed in a glass with a capacity of 250 cm, 50 cm, pour the
mixture of acids and evaporated to start the selection, the dense white fumes of sulphuric anhydride. After cooling, to the residue add 60−70 cm
of hot water and heated to dissolve the salts, then the solution was cooled and transferred to volumetric flask with a capacity of 200 cm
.
Solution in a volumetric flask, topped to the mark with water and mix.
Part of the solution filtered through a dry thick filter into a dry flask.
For oxidation of manganese taken aliquot part of the solution was 50 cmin a conical flask with a capacity of 250 cm
, 10 cm poured
sulphuric acid, diluted 1:1, dilute with water to obtain a volume of approximately 80 cm
, add 5 cm
of phosphoric acid, heated to boiling, and add 0.3 g of potassium periodate. The resulting solution was stirred to dissolve the potassium periodate, boiled for 5 min to detect the color and then placed the flask with the solution for 30 min on sand bath. During heating and boiling water is added to maintain the original liquid volume. Chilled colored solution was transferred to volumetric flask with a capacity of 100 cm
, pre-washed by water, containing reductive substances, dilute this to the mark with water, mix. Solution comparison is water. Measure the optical density of the test solution on a photoelectrocolorimeter or spectrophotometer, given that a maximum of light absorption of solutions corresponds to the wavelength of 528 nm.
The solution in the reference experiment is prepared simultaneously with the analyzed solution with the same amount of reacti
the second world war.
3.2.1. Construction of calibration curve
Eight conical flasks with a capacity of 250 cmflow consistently 0; 0,5; 1,0; 2,0; 4,0; 6,0; 8,0; 10,0 cm
standard solution A, which corresponds to 0; 0,05; 0,1; 0,2; 0,4; 0,6; 0,8; 1,0 mg of manganese, is added to 20 cm
of the mixture of acids and diluted to volume is approximately 45 cm
, add 5 cm
of phosphoric acid and then act as described in section 3.2.
As a solution comparison, use water.
Measure the optical density of solutions as specified in claim 3.1.
According to the obtained values of optical density and known mass of manganese in the solutions to build the calibration graph.
4. PROCESSING OF THE RESULTS
4.1. Mass fraction of manganese () in percent (the analysis according to claim 3.1) is calculated according to the formula
where is the mass of manganese was found in the calibration graphics mg;
— the weight of the portion of silumin,
4.2. Mass fraction of manganese () in percent (the analysis according to claim 3.2) is calculated according to the formula
where is the mass of manganese was found in the calibration graphics mg;
— the total volume of solution, cm
;
— volume aliquote part of the solution, cm
;
— the weight of the portion of silumin,
4.3. Allowable absolute differences of the results of the parallel definitions should not exceed the values given in the table.
| Mass fraction of manganese, % | Allowable absolute differences, % | |
| convergence | reproducibility | |
| From 0,005 to 0,010 incl. | 0,002 | 0,003 |
| SV. 0,010 «0,030 « | 0,005 | 0,008 |
| «0,030» 0,100 « | 0,007 | 0,010 |
| «0,100» 0,250 « | 0,010 | 0,020 |
| «0,250» 0,800 « | 0,030 | 0,050 |
(Changed edition, Rev. N 2).
ATOMIC ABSORPTION METHOD
The essence of the method consists in measuring the atomic absorption of manganese in the flame acetylene-air at a wavelength of 279.5 nm.
5. APPARATUS, REAGENTS AND SOLUTIONS
Spectrometer atomic absorption model of Perkin-Elmer, «Saturn» or similar.
Lamp with a hollow cathode, is intended for the determination of manganese.
Acetylene in cylinders for technical GOST 5457−75.
Muffle furnace with thermostat, providing a temperature of 1000 °C.
Sulfuric acid GOST 4204−77, diluted 1:1.
Hydrochloric acid by the GOST 3118−77, diluted 1:1.
Hydrogen peroxide according to GOST 10929−76, a solution with a mass fraction of 3%.
Cup platinum, silver, Nickel.
Aluminium stamps A-999 according to GOST 11069−74*.
________________
* On the territory of the Russian Federation GOST 11069−2001. — Note the CODE.
The solution of aluminum And 20 g/DMis prepared as follows: 10.0 g of aluminum is placed in a beaker with a capacity of 600 cm
, add 250 cm
of hydrochloric acid diluted 1:1, and dissolved under heating with adding 1 cm
of Nickel chloride. The solution was cooled, transferred to a volumetric flask with a capacity of 500 cm
, is diluted to the mark with water and mix.
Silicon dioxide according to GOST 9428−73.
A solution of silicon B, 1 g/DM: 2,14 g of finely crushed in an agate or plexiglass mortar and preheated for one hour at a temperature of 1000 °C silicon dioxide is fused in a platinum crucible with 15 g of anhydrous sodium carbonate at a temperature of 900 °C to produce a clear float for 15 min. the Melt is dissolved in water by heating in a platinum, silver or Nickel Cup. The solution was cooled, transferred into a measuring flask with volume capacity of 1000 cm
, is diluted to the mark with water and mix. Solution store in a plastic container.
Sodium chloride according to GOST 4233−77.
A solution of sodium oxide, 100 g/DMis prepared as follows: 190 g dried at 105 °C for 30 min. sodium chloride dissolved in water. The solution was transferred into a measuring flask with volume capacity of 1000 cm
, adjusted to the mark with water and mix.
Potassium permanganate according to GOST 20490−75.
Manganese metal in the form of chips according to GOST 6008−82; cleaning the oxide film is carried out according to sect.2.
Standard solutions of manganese
Solution D: 2,8767 g potassium permanganate placed in a beaker with a capacity of 600 cm, were placed in a glass*, add 200 cm
of water and 20 cm
of sulfuric acid solution, dissolved by heating. To the solution was added dropwise a solution of hydrogen peroxide to bleaching, evaporated to fumes of sulfuric acid. The residue after cooling is diluted with water, transferred into a measuring flask with volume capacity of 1000 cm
, adjusted to the mark with water and stirred or 1,000 g of metallic manganese was dissolved in a beaker with a capacity of 600 cm
under the watch glass 20 cm
of sulfuric acid solution with the addition of 100 cm
of water. The solution was boiled for 2−3 min, cooled, transferred into a measuring flask with volume capacity of 1000 cm
, made up to the mark with water and mix.
________________
* The text matches the original. — Note the CODE.
1 cmof solution D contains 1 mg of manganese.
Solution: pipetted 20 cmof solution D in a volumetric flask with a capacity of 200 cm
, adjusted to the mark with water and mix; prepare before use.
1 cmof solution E contains 0.1 mg of manganese.
The anhydrous sodium carbonate according to GOST 83−79.
Sodium hydroxide according to GOST 4328−77, a solution with a mass fraction of 30%.
Nickel chloride according to GOST 4038−79, a solution with a mass fraction of 0.2%.
Methyl orange, solution with a mass fraction of 0.1%.
6. ANALYSIS
6.1. Weighed samples of the silumin weighing 0.5 g were placed in a glass with a capacity of 250 cmand poured 20 cm
of the sodium hydroxide solution. At the end of the reaction the solution is heated on a sand bath until complete dissolution of alloy, add approximately 100 cm
of water and carefully to the cooled solution poured 50 cm
of hydrochloric acid diluted 1:1. The solution is heated to enlightenment, add 1 cm
of hydrogen peroxide solution and boiled for 3−5 min for the destruction of its excess.
The solution was cooled and transferred to volumetric flask with a capacity of 250 cm, was adjusted to the mark with water and mix. Simultaneously conduct control experience, using all the reagents by dissolving samples of the silumin with the addition of 20 cm
of a solution of aluminium A.
Measure the atomic absorption of manganese in the sample solution, the solution in the reference experiment and in solutions, prepared to build a calibration curve at a wavelength of 279.5 nm flame air-acetylene.
Mass fraction of manganese is determined according to the calibration schedule, which build on every shot
.
6.2. Construction of calibration curve
Nine volumetric flasks with a capacity of 250 cmflow sequentially through 12.5 cm
of solution A with 7 cm
of solution and accordingly 0; 0,25; 0,5; 1,0; 2,5; 5,0; 12,5; 25,0; 40,0 cm
of solution E, which corresponds to 0; 0,005; 0,01; 0,02; 0,05; 0,10; 0,25; 0,5; 0,8% mass fraction of manganese in silumin.
The solutions were adjusted with water to a volume of 100 cmand slowly portions, stirring thoroughly, pour 25 cm
of a solution, add 3−4 drops of methyl orange indicator and drop hydrochloric acid diluted 1:1, until the color changes of the indicator in red. Then the solutions in the flasks was adjusted to the mark with water, mix and measure the atomic absorption of manganese, as specified in clause 6.1.
According to the obtained values of atomic absorption solutions and the known values of the mass fraction of manganese build the calibration graph.
7. PROCESSING OF THE RESULTS
7.1. Mass fraction of manganese in percent find the calibration schedule, minus the reference experiment.
7.2. Allowable absolute differences of the results of the parallel definitions should not exceed the values given in the table.
Sec. 5−7. (Added, Rev. N 2).
