GOST 25278.1-82
GOST 25278.1−82 Alloys and alloys of rare metals. Methods for determination of aluminium (with Change No. 1)
GOST 25278.1−82
Group B59
STATE STANDARD OF THE USSR
ALLOYS AND ALLOYS OF RARE METALS
Methods for determination of aluminium
Alloys and foundry alloys of rare metals. Methods for determination of aluminium
AXTU 1799
The validity of c 01.07.83
to 01.07.93*
_______________________________
* Expiration removed
according to the Protocol of the Intergovernmental Council
for standardization, Metrology and certification
(IUS N 2, 1993). — Note the manufacturer’s database.
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
PERFORMERS
Yu. A. Karpov, E. G. Nembrini, V. G., Miscreants, G. N. Andrianov, E. S. Danilin, M. A. Desyatkova L. I. Kirsanova, T. M. Malyutina, Y. F. Markov, V. M. Mikhailov, L. A. Nikitina, L. G. Obruchkova, N. Rasnitsyn, N. Suvorova, L. N. Filimonov
2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee for standards from
3. The period of examination — 1993
The frequency of inspection is 5 years.
4. INTRODUCED FOR THE FIRST TIME.
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
The designation of the reference document referenced |
Item number |
GOST 61−75 |
2.1, 3.1 |
GOST 1381−73 |
3.1, 4.1 |
GOST 3118−77 |
2.1, 3.1 |
GOST 3760−79 |
4.1 |
GOST 3769−78 |
4.1 |
GOST 4204−77 | 4.1 |
GOST 4217−77 |
4.1 |
GOST 4328−77 |
2.1, 3.1 |
GOST 5817−77 | 2.1, 3.1 |
GOST 5823−78 |
2.1, 3.1 |
GOST 10652−73 |
2.1, 4.1 |
GOST 10929−76 |
2.1 |
GOST 11069−74 |
2.1, 3.1, 4.1 |
GOST 25278.10−82 |
3.2 |
GOST 26473.0−85 |
1.1 |
6. The validity of the standard extended
7. REPRINT (November 1988) with amendment No. 1, approved in October 1987 (ICS 1−88).
This standard specifies the method of chelatometric determination of aluminium:
from 5 to 20% in alloys (ligatures) based on niobium (components: tungsten not exceeding 25%, molybdenum not more than 25%, zirconium not more than 30%);
from 10 to 20% in the binary alloys zirconium-aluminum.
1. GENERAL REQUIREMENTS
1.1. General requirements for methods of analysis and security requirements — according to GOST 26473.0−85.
(Changed edition, Rev. N 1).
2. METHOD CHELATOMETRIC DETERMINATION OF ALUMINIUM IN ALLOYS BASED ON NIOBIUM CONTAINING ZIRCONIUM
The method is based on back titration of excess Trilon B added to bind aluminum, with a solution of zinc salt at a pH of 5.5 with indicator kylinalove orange. Niobium and tungsten mask tartaric acid; complexonate molybdenum destroy hydrogen peroxide.
2.1. Apparatus, reagents and solutions
Muffle furnace with thermostat providing temperatures up to 1000 °C.
Tile electric.
Bath water.
Analytical scale.
Libra technical.
The quartz crucibles high capacity of 40 cm.
Conical flasks with a capacity of 250 cm.
Volumetric flasks with a capacity of 500 and 1000 cm.
Pipettes without dividing by 10 cm.
Pipette with divisions of 5 cm.
Measuring beakers with a capacity of 25, 50 and 100 cm.
Burettes with a capacity of 10 and 25 cm.
Glasses chemical glass with a capacity of 250 cm.
Porcelain Cup with a capacity of 200 cm.
Watch-glasses.
Indicator paper Congo.
Universal indicator paper.
Hydrogen peroxide according to GOST 10929−76.
Potassium preservatory according to GOST 7172−76.
Tartaric acid according to GOST 5817−77, a solution of 150 g/DM.
Sodium hydroxide according to GOST 4328−77, a solution of 250 g/DM.
Methenamine according to GOST 1381−73.
Acetic acid GOST 61−75, solution 1 mol/DM: 5.6 cmof glacial acetic acid diluted to 100 cmwith water.
Selenology orange, an aqueous solution of 1 mg/cm.
Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid, 2-water (Trilon B) according to GOST 10652−73, solution 0,05 mol/DM, is prepared as follows: 18.6 g Trilon B dissolved in water with heating (if the solution is turbid, it is filtered), transferred to a volumetric flask with a capacity of 1 DM, is cooled and adjusted to the mark with water.
Zinc acetate according to GOST 5823−78, solution 0,05 mol/DM.
Zinc metal granulated.
Hydrochloric acid by the GOST 3118−77, diluted 1:1 and 1:5.
Zinc chloride, solution 0.05 mol/DM: 1,6345 g of zinc metal is placed in a beaker with a capacity of 250 cmand dissolved by heating in hydrochloric acid (1:5). The solution was transferred to a porcelain Cup and evaporated to small volume on a water bath. The addition of water and evaporation was repeated several times. The solution was then transferred to a volumetric flask with a capacity of 500 cmand was adjusted to the mark with water.
Aluminium metal according to GOST 11069−74*, grade A-99.
______________
* On the territory of the Russian GOST 11069−2001, here and hereafter. — Note the manufacturer’s database.
A standard solution of aluminium containing 1 mg/cmaluminum: 0.1 g of aluminum metal is placed in a beaker with a capacity of 250 cm, flow 50 cmhydrochloric acid (1:1), cover with a watch glass and dissolve with a moderate heat. The solution was transferred to volumetric flask with a capacity of 1 DM, adjusted to the mark with water and mix.
Establish the relation between the solution of Trilon B and a solution of zinc salts (chloride or acetate): in a conical flask with a capacity of 250 cmpoured from the burette 10 cmof the solution Trilon B, add 90 cmwater and 5 cmof acetic acid, 1 g of hexamine and 0.5 cmof the solution kylinalove orange; titrated with a solution of zinc salt before moving to the yellow-orange color to purple-red.
The ratio () of the volume of the solution Trilon B and zinc salt described by the formula
,
where — volume of solution Trilon B taken for titration, cm;
the volume of the solution of zinc salt, spent on titration, sm.
Set the concentration of the solution Trilon B by aluminum in a conical flask with a capacity of 250 cmtaken 10 cmof a standard solution of aluminium, pour 2 cmof a solution of tartaric acid and diluted to 100 cmwith water and neutralized with sodium hydroxide solution first indicator paper Congo before transition of colouring from blue to purple, and then universal indicator paper until a pH of 4.0. Pour 5 cmof acetic acid, add 1 g hexamine, poured from the burette 10 cmsolution of Trilon B. the Solution is heated and boiled for 5 min. after cooling, add 0.5 cmof the solution kylinalove orange and titrate the excess Trilon B with a solution of zinc salt before moving to the yellow-orange color in red and purple, persisting for 20 to 30 C.
The concentration of the solution Trilon B () on aluminium in g/cmis calculated by the formula
,
where — volume of solution Trilon B added to the analyzed solution, cm;
— the volume of solution of zinc chloride, used for titration, cm;
— the ratio of the volume of the solution Trilon B and zinc salt;
the weight of aluminium,
(Changed edition, Rev. N 1).
2.2. Analysis
A portion of the sample weighing 0.1 g was placed in a quartz crucible, add 2−4 g of potassium persulphate and fused in a muffle at a temperature of 700−800 °C to obtain a homogeneous melt. The smelt is dissolved by heating in 4 cmof tartaric acid (a larger number prevents the titration of aluminium). The solution was transferred to a conical flask with a capacity of 250 cm, dilute with water to 100 cmand neutralized with sodium hydroxide solution on the paper of the Congo before transition of colouring paper from blue to purple, and then universal indicator paper until a pH of 4.0, pour 5 cmof acetic acid, add 1 g hexamine, poured from the burette accurately measured volume of solution Trilon B in excess of the equivalent in aluminium 2−3 cm. The solution is heated and boiled for 5 min. after cooling, add 1 cmof hydrogen peroxide (if the sample is molybdenum) and leave for 3−5 minutes for the quantitative destruction of complexonate molybdenum, then pour 0.5 cmof the solution kylinalove orange and titrate the excess Trilon B with a solution of zinc salt before moving to the yellow-orange color in red and purple, persisting for 20−30 with
.
2.3. Processing of the results
2.3.1. Mass fraction of aluminium () in percent is calculated by the formula
,
where is the concentration of the solution Trilon B in aluminium, g/cm;
— volume of solution Trilon B added to the analyzed solution, cm;
the volume of the solution of zinc salt, used for titration, cm;
— the ratio of the volume of the solution Trilon B and zinc salt;
— the weight of the portion of the sample,
2.3.2. Discrepancies between the results of two parallel determinations and the results of the two analyses for alloys that do not contain moleben, shall not exceed the values of permissible differences given in table.1.
Table 1
Mass fraction of aluminum, % |
The allowable divergence, % |
5,0 |
0,2 |
10,0 |
0,3 |
20,0 | 0,6 |
2.3.3. Discrepancies between the results of two parallel determinations and the results of the two analyses for alloys containing molybdenum should not exceed the values of permissible differences given in table.2.
Table 2
Mass fraction of aluminum, % |
The allowable divergence, % |
5,0 |
0,3 |
10,0 |
0,6 |
20,0 |
1,1 |
2.3.1−2.3.3. (Changed edition, Rev. N 1).
3. METHOD CHELATOMETRIC DETERMINATION OF ALUMINIUM IN ALLOYS BASED ON NIOBIUM CONTAINING ZIRCONIUM
The method is based on alkaline the separation of aluminum from niobium, zirconium, and back titration of excess Trilon B added to bind aluminum, with a solution of zinc salt at a pH of 5.5 with indicator kylinalove orange. The tungsten mask tartaric acid; complexonate molybdenum destroy hydrogen peroxide.
3.1. Apparatus, reagents and solutions
Muffle furnace with thermostat providing temperatures up to 1000 °C.
Tile electric.
Bath water.
Analytical scale.
Libra technical.
Nickel crucibles.
Conical flasks with a capacity of 250 cm.
Volumetric flasks with a capacity of 500 and 1000 cm.
Pipettes without dividing by 10 cm.
Pipette with divisions of 5 cm.
Measuring beakers with a capacity of 25, 50 and 100 cm.
Burettes with a capacity of 10 and 25 cm.
Glasses chemical glass with a capacity of 250 cm
Porcelain Cup with a capacity of 200 cm.
Funnels, glass, conical.
Watch-glasses.
Filters tight (blue ribbon).
Indicator paper Congo.
Universal indicator paper.
Hydrogen peroxide according to GOST 10929−76.
Tartaric acid according to GOST 5817−77, a solution of 150 g/DM.
Sodium hydroxide according to GOST 4328−77, solutions of 250 and 30 g/DM.
Methenamine according to GOST 1381−73.
Acetic acid GOST 61−75, solution 1 mol/DM: 5.6 cmof glacial acetic acid diluted to 100 cmwith water.
Selenology orange, an aqueous solution of 1 mg/cm.
Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid 2-water (Trilon B) according to GOST 10652−73, solution 0,05 mol/l; prepared as follows: 18.6 g Trilon B dissolved in water with heating (if the solution is turbid, it is filtered), transferred to a volumetric flask with a capacity of 1 DM, is cooled and adjusted to the mark with water.
Zinc acetate according to GOST 5823−78, solution 0,05 mol/DM.
Zinc metal granulated GOST 989−75.
Hydrochloric acid by the GOST 3118−77, diluted 1:1 and 1:5.
Zinc chloride, solution 0.05 mol/DM: 1,6345 g of zinc metal is placed in a beaker with a capacity of 250 cmand dissolved by heating in hydrochloric acid (1:5). The solution was transferred to a porcelain Cup and evaporated to small volume on a water bath. The addition of water and evaporation was repeated several times. The solution was then transferred to a volumetric flask with a capacity of 500 cmand was adjusted to the mark with water.
Aluminium metal according to GOST 11069−74, grade A-99.
A standard solution of aluminium containing 1 mg/cmof aluminium: 1.0 g aluminum metal is placed in a beaker with a capacity of 250 cm, flow 50 cmhydrochloric acid (1:1), cover with a watch glass and dissolve with a moderate heat. The solution was transferred to volumetric flask with a capacity of 1 DM, adjusted to the mark with water and mix.
Set the ratio of the solution Trilon B solution and a solution of zinc salt (chloride or acetate): in a conical flask with a capacity of 250 cmpoured from the burette 10 cmof the solution Trilon B, add 90 cmwater, 5 cmacetic acid, 1 g of hexamine and 0.5 cmkylinalove orange solution and titrated with a solution of zinc salt before moving to the yellow-orange color to purple-red.
The ratio () of the volume of the solution Trilon B and zinc salt described by the formula
,
where — volume of solution Trilon B taken for titration, cm;
the volume of the solution of zinc salt, spent on titration, sm.
Set the concentration of the solution Trilon B by aluminum in a conical flask with a capacity of 250 cmtaken 10 cmof a standard solution of aluminium, pour 2 cmof a solution of tartaric acid and diluted to 100 cmwith water and neutralized with 25% sodium hydroxide solution first indicator paper Congo before transition of colouring from blue to purple, and then universal indicator paper until a pH of 4.0. Pour 5 cmof acetic acid, add 1 g hexamine, poured from the burette 10 cmsolution of Trilon B. the Solution is heated and boiled for 5 min. after cooling, add 0.5 cmof the solution kylinalove orange and titrate the excess Trilon B with a solution of zinc salt before moving to the yellow-orange color in red and purple, persisting for 20 to 30 C.
The concentration of the solution Trilon B () on aluminium in g/cmis calculated by the formula
,
where — volume of solution Trilon B added to the analyzed solution, cm;
the volume of the solution of zinc salt, used for titration, cm;
— the ratio of the volume of the solution Trilon B and zinc salt;
the weight of aluminium,
(Changed edition, Rev. N 1).
3.2. Analysis
A portion of the sample weighing 0.1 g was placed in a Nickel crucible with 2−3 g of sodium hydroxide, heated on a hotplate to melt the sodium hydroxide. Then transfer the crucible in the muffle, heated to 400 °C, gradually raising the temperature in the muffle up to 700−800 °C, and maintained at this temperature to obtain a homogeneous melt. The smelt is leached of 70−80 cmof water when heated. The solution is filtered through a dense paper filter (blue ribbon); the filter cake was washed 2−3 times 3% sodium hydroxide solution.
The precipitate of hydroxides remain for the determination of zirconium GOST 25278.10−82.
The filtrate and the washings collected in a conical flask with a capacity of 250 cm, their total should not exceed 100 cm. If the sample contains tungsten, pour 4 cmof tartaric acid and neutralize the filtrate with hydrochloric acid on the paper of the Congo before transition of colouring paper from red to purple, and then universal indicator paper until a pH of 4.0. Pour 5 cmof acetic acid, add 1 g hexamine, poured from the burette accurately measured volume of Trilon B in excess of the equivalent in aluminium 2−3 cm. The solution is heated and boiled for 5 min. after cooling, add 1 cmof hydrogen peroxide (if the sample is molybdenum) and leave to stand 3−5 minutes for the quantitative destruction of complexonate molybdenum, then pour 0.5 cmof the solution kylinalove orange and titrate the excess Trilon B with a solution of zinc salt before moving to the yellow-orange color in red and purple, persisting for 20−30
C.
3.3. Processing of the results
3.3.1. Mass fraction of aluminium () in percent is calculated by the formula
,
where is the concentration of the solution Trilon B in aluminium, g/cm;
— volume of solution Trilon B added to the analyzed solution, cm;
the volume of the solution of zinc salt, used for titration, cm;
— the ratio of the volume of the solution Trilon B and zinc salt;
— the weight of the portion of the sample,
3.3.2. Discrepancies between the results of two parallel determinations and the results of the two tests should not exceed the values of permissible differences given in table.3.
Table 3
Mass fraction of aluminum, % |
The allowable divergence, % |
5,0 |
0,3 |
10,0 |
0,6 |
20,0 |
1,1 |
3.3.1,
4. METHOD CHELATOMETRIC DETERMINATION OF ALUMINIUM BINARY ALLOYS ZIRCONIUM-ALUMINIUM
The method is based on sequential complexometric titration of zirconium and aluminium in the same solution. Definition of Zirconia is carried out by direct titration in sulfuric acid 0.5 mol/DMsolution in the presence of ammonium sulfate indicator kylinalove orange. Aluminium is determined in the same solution back titration of an excess Trilon B with a solution of zinc salt at a pH of 5.5 with indicator kylinalove orange.
4.1. Apparatus, reagents and solutions
Tile electric.
Bath water.
Analytical scale.
Libra technical.
Conical flasks with a capacity of 250 cm.
Volumetric flasks with a capacity of 500 and 1000 cm.
Pipettes without dividing by 5 and 10 cm.
Pipettes with graduation marks at 5 and 10 cm.
Measuring beakers with a capacity of 25, 50 and 100 cm.
Burettes with a capacity of 10 and 25 cm.
Glasses chemical glass with a capacity of 250 cm.
Porcelain Cup with a capacity of 200 cm.
Watch-glasses.
Indicator paper Congo.
Universal indicator paper.
Sulfuric acid according to GOST 4204−77.
Ammonium sulfate according to GOST 3769−78, a solution of 20 g/DM.
Potassium nitrate according to GOST 4217−77.
Ammonia according to GOST 3760−79 diluted 1:1.
Methenamine according to GOST 1381−73.
Acetic acid GOST 61−75, solution 1 mol/DM: 5.6 cmof glacial acetic acid diluted to 100 cmwith water.
Selenology orange indicator mixture: 0.2 g kylinalove orange ground in a mortar with 20 g of potassium nitrate.
Salt is the disodium Ethylenediamine-N, N, N', N'-tetraoxane acid, 2-water (Trilon B) according to GOST 10652−73, solution 0,05 mol/l; prepared as follows: 18.6 g Trilon B dissolved in water with heating (if the solution is turbid, it is filtered); transferred to a volumetric flask with a capacity of 1 DM, is cooled and adjusted to the mark with water.
Zinc metal granulated.
Hydrochloric acid by the GOST 3118−77, diluted 1:1 and 1:5.
Zinc chloride, solution 0.05 mol/DM: 1,6345 g of zinc metal is placed in a beaker with a capacity of 250 cmand dissolved by heating in hydrochloric acid (1:5). The solution was transferred to a porcelain Cup and evaporated to small volume on a water bath. Add water and evaporation was repeated several times. The solution was then transferred to a volumetric flask with a capacity of 500 cmand was adjusted to the mark with water.
Aluminium metal according to GOST 11069−74, grade A-99.
A standard solution of aluminium containing 1 mg/cmof aluminium: 1.0 g aluminum metal is placed in a beaker with a capacity of 250 cm, flow 50 cmhydrochloric acid (1:1), cover with a watch glass and dissolve with a moderate heat. The solution was transferred to volumetric flask with a capacity of 1 DM, adjusted to the mark with water and mix.
Set the ratio of the volume of the solution Trilon B and zinc chloride in conical flask with a capacity of 250 cmpoured from the burette 10 cmof the solution Trilon B, add 90 cmwater, 5 cmacetic acid, 1 g of hexamine and 0.5 cmof the solution kylinalove orange; titrated with a solution of zinc salt before moving to the yellow-orange color to purple-red.
The ratio () of the volume of the solution Trilon B and zinc chloride is calculated by the formula
,
where — volume of solution Trilon B taken for titration, cm;
— the volume of solution of zinc chloride, spent on titration, sm.
Set the concentration of the solution Trilon B by aluminum in a conical flask with a capacity of 250 cmtaken 10 cmof standard aluminium solution, dilute with water to 100 cm, neutralized with aqueous ammonia, first to the paper of the Congo to the transition of color from blue to purple, and then universal indicator paper until a pH of 4.0. Pour 5 cmof acetic acid, add 1 g hexamine, poured from the burette 10 cmsolution of Trilon B. the Solution is heated and boiled for 5 min. after cooling, add about 0.1 g of indicator mixture and titrate the excess Trilon B with a solution of zinc chloride to the transition yellow-orange color in red and purple, persisting for 20 to 30 C.
The concentration of the solution Trilon B () on aluminium in g/cmis calculated by the formula
,
where — volume of solution Trilon B added to the analyzed solution, cm;
— the volume of solution of zinc chloride, used for titration, cm;
— the ratio of the volume of the solution Trilon B and zinc salt;
the weight of aluminium,
4.2. Analysis
A portion of the sample weighing 0.1 g was placed in a conical flask with a capacity of 250 cmand dissolved by heating in 2.5 cmof concentrated sulfuric acid with constant stirring. Upon dissolution of the alloy solution was cooled, poured 100 cmof solution of ammonium sulfate, again heated to boiling and boiled for 3 minutes In a hot solution add about 0,1 g of indicator mixture and titrate kylinalove orange cubic Zirconia with a solution of Trilon B before moving bright crimson coloring in yellow.
The solution was cooled, neutralized with aqueous ammonia first paper of the Congo before transition of colouring paper from blue to purple, and then universal indicator paper until a pH of 4.0, add 5 cmof acetic acid, 1 g of hexamine, poured from the burette accurately measured volume of solution Trilon B in excess of the equivalent in aluminium 2−3 cm. The solution is heated and boiled for 5 min. after cooling, add about 0.1 g of indicator mixture kylinalove orange and titrate the excess Trilon B with a solution of zinc chloride to the transition of the orange-yellow color in red and purple, persisting for 20 to 30 C.
4.3. Processing of the results
4.3.1. Mass fraction of aluminium () in percent is calculated by the formula
,
where is the concentration of the solution Trilon B in aluminium, g/cm;
— volume of solution Trilon B added to the analyzed solution, cm;
— the volume of solution of zinc chloride, used for titration, cm;
— the ratio of the volume of the solution Trilon B and zinc salt;
— the weight of the portion of the sample,
4.3.2. Discrepancies between the results of two parallel determinations and the results of the two tests should not exceed the values of permissible differences given in table.4.
Table 4
Mass fraction of aluminum, % |
The allowable divergence, % |
10,0 |
0,4 |
15,0 |
0,5 |
20,0 |
0,6 |
4.3.1,