GOST 2604.10-77
GOST 2604.10−77 alloy Cast iron. Method of determining titanium (with Amendments No. 1, 2)
GOST 2604.10−77
Group B09
INTERSTATE STANDARD
ALLOY CAST IRON
Method of determining titanium
Alloy cast iron. Method for determination of titanium
ISS 77.080.10
AXTU 0809
Date of introduction 1978−01−01
The decision of the State standards Committee of the USSR Council of Ministers dated 22 March 1977, N 680 date of introduction is established 01.01.78
Limitation of actions taken by Protocol No. 2−92 of the Interstate Council for standardization, Metrology and certification (ICS 2−93)
REPLACE GOST 2604−44 in part of sec. XI
EDITION with Amendments No. 1, 2 approved in December 1982, April 1985 (IUS 3−83, 7−85).
This standard sets the photometric method for the determination of titanium (with a mass fraction of from 0.01 to 1.5%) in the doped iron.
The method is based on formation of yellow-orange color complex compounds of titanium with diantipyrylmethane in hydrochloric acid environment. The reaction proceeds at a molar concentration equivalent to 1−4 mol/DM.
The interfering influence of iron (III) and vanadium (V) eliminate the addition of ascorbic acid.
1. GENERAL REQUIREMENTS
1.1. General requirements for method of analysis according to GOST 28473−90.
2. APPARATUS, REAGENTS AND SOLUTIONS
Spectrophotometer or photoelectrocolorimeter.
Sulfuric acid GOST 4204−77, diluted 1:4 and 1:9.
Nitric acid GOST 4461−77.
Ascorbic acid, 10% freshly prepared solution.
Hydrochloric acid by the GOST 3118−77 with molar concentration of equivalent of 1 mol/l, diluted 1:1 and 1:100.
Diantipyrylmethane, a solution with a mass fraction of 5% freshly prepared: 50 g diantipyrylmethane dissolve in hydrochloric acid with molar concentration of equivalent of 1 mol/DM, adjusted to a volume of 1 DMhydrochloric acid of the same concentration, and stirred.
Carbonyl iron according to GOST 13610−79, 0,2% solution, prepared as follows: into a glass with a capacity of 300 cmis placed 2 g of carbonyl iron, poured 80 cmof sulphuric acid, diluted 1:4, the beaker cover watch glass, and moderately heated until complete dissolution of the sample. Then, opening a watch glass, carefully poured drop by drop nitric acid until the termination of foaming and the solution was evaporated until the appearance of sulphuric acid fumes. The contents of the beaker cooled, poured 100 cmof water, heated to dissolve the salts, and cooled. The solution is transferred into a measuring flask with volume capacity of 1000 cm, made up to the mark with water and mix.
Titanium metal according to GOST 17746−96, standard solutions of titanium.
A standard solution with A mass concentration of 0.0001 g/cm: 0.1 g of titanium metal is dissolved with moderate heating in 15 cmof sulfuric acid. After complete dissolution of the sample is added to oxidise titanium 1 cmof nitric acid. The solution was evaporated until the appearance of sulphuric acid fumes to remove oxides of nitrogen, poured 30 cmof water and again evaporated.
Transfer the solution into a volumetric flask with a capacity of 1 DM, made up to the mark with sulfuric acid diluted 1:9, and stirred.
Standard solution B with a mass concentration of 0,00001 g/cm: 100 cmstandard solution And transferred to a volumetric flask with a capacity of 1 DM, made up to the mark with sulfuric acid diluted 1:9, and stirred.
(Changed edition, Rev. N 2).
3. ANALYSIS
3.1. To determine the mass fraction of titanium to take the next sample of cast iron: a mass of 0.5 g (when the mass fraction of titanium from 0.01 to 0.6%), with a mass of 0.2 g (with a mass fraction of titanium is more than 0.6 to 1.5%).
The weight of cast iron placed in a glass with a capacity of 300 cm, 40 cm pouredsulphuric acid, diluted 1:4, the beaker cover watch glass, and moderately heated until complete dissolution of the sample. Then, opening a watch glass, carefully poured drop by drop nitric acid until the termination of foaming and the solution was evaporated until the appearance of sulphuric acid fumes. The contents of the beaker cooled, pour 50 cmof water and heated to dissolve the salts.
In cases where the sample is not soluble in sulfuric acid, diluted 1:4, the dissolution of lead in 40 cmof hydrochloric acid, adding dropwise nitric acid to dissolve sample. The solution was evaporated to dryness. The dry residue moistened with 10 cmof hydrochloric acid, heated for 2−3 min, poured 50 cmof water and heated to dissolve the salts.
Silicic acid, and graphite was filtered, the filter «white ribbon». The filter cake was washed several times with hydrochloric acid, diluted 1:100.
The solution was transferred to a volumetric flask with a capacity of 100 cm, made up to the mark with water and mix.
Aliquote part of the solution to 20 cm(when the mass fraction of titanium from 0.01 to 0.1%) and 5 cm(when the mass fraction of titanium from 0.1 to 1.5%) is placed into two volumetric flasks with a capacity of 100 cm.
In each flask pour 5 cmof a 10% ascorbic acid solution, mix and leave for 5−7 min until complete recovery of ferric iron and pentavalent vanadium. Then add 15 cmof hydrochloric acid diluted 1:1. One flask pour 10 cmof diantipyrylmethane solution with a mass fraction of 5%. The solution in the second flask (without diantipyrylmethane) is solution comparisons. To both flasks add water to the mark and mix.
The optical density of the solutions measured after 20−30 min on a photoelectrocolorimeter with a blue color filter at a wavelength of 390 nm.
Mass fraction of titanium in the percentage found by the calibration schedule.
(Changed edition, Rev. N
1, 2).
3.2. Construction of calibration curve when the mass fraction of titanium from 0.01 to 0.1%.
Aliquote parts of a solution of carbonyl iron 50 cmplaced in eleven volumetric flasks with a capacity of 100 cm.
In ten volumetric flasks poured consistently 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 cmstandard solution B titanium, which corresponds to 1; 2; 3; 4; 5; 6; 7; 8; 9; 10 micrograms of titanium in relation to the original mounting of cast iron 0.5 g and aliquote parts of a solution of 20 cm.
In each flask pour 5 cmof a 10% ascorbic acid solution, mix and leave for 10−15 min until complete recovery of ferric iron and pentavalent vanadium. Then add 5 cmof hydrochloric acid diluted 1:1. To all flasks add 25 cmdiantipyrylmethane solution with a mass fraction of 5%.
In each flask pour water up to the mark and mix. The optical density of the solutions measured after 20−30 min on a photoelectrocolorimeter with a blue filter at a wavelength of 390 nm.
Solution comparison is the solution in the flask containing carbonyl iron, not titanium that has undergone all stages of analysis, to which add the same reagents as the sample.
On the found values of optical density of the solutions and their corresponding titanium concentration to build a calibration curve.
(Changed edition, Rev. N 1, 2)
.
3.2. Construction of calibration curve for titanium from 0.1 to 0.6%
Aliquote parts of carbonyl iron 12.5 cmplaced in seven volumetric flasks with a capacity of 100 cm.
In six volumetric flasks poured consistently 2,5; 5,0; 7,5; 10; 12,5 and 15.0 cmstandard solution B titanium, which corresponds to 10; 20; 30; 40; 50; 60 micrograms of titanium in relation to the original mounting of cast iron 0.5 g and aliquote parts of a solution of 5 cm.
In each flask pour 5 cmof a 10% ascorbic acid solution, mix and leave for 5−7 min until complete recovery of ferric iron and pentavalent vanadium. Then add 15 cmof hydrochloric acid diluted 1:1. All flasks is poured 10 cmof diantipyrylmethane solution with a mass fraction of 5%.
In each flask pour water up to the mark and mix. The optical density of the solutions measured after 45 min on a photoelectrocolorimeter with a blue color filter at a wavelength of 390 nm.
A solution of comparison is the solution of the seventh flask containing carbonyl iron, carried through all the stages of analysis, to which add the same reagents as the sample, but not containing titanium.
On the found values of optical density of the solutions and their corresponding titanium concentration to build a calibration curve
.
3.3. Construction of calibration curve for the mass fraction of titanium from 0.6 to 1.5%
Aliquote parts of a solution of carbonyl iron for 5 cmis placed at eleven volumetric flasks with a capacity of 100 cm.
In ten volumetric flasks poured consistently 6,0; 7,0; 8,0; 9,0; 10,0; 11,0; 12,0; 13,0; 14,0 and 15.0 cmstandard solution B titanium, which corresponds to 60; 70; 80; 90; 100; 110; 120; 130; 140; 150 micrograms of titanium in relation to the original mounting of cast iron 0.2 g and aliquote parts of a solution of 5 cm.
In each flask pour 2 cmof a 10% ascorbic acid solution, mix and leave for 5−7 min until complete recovery of ferric iron and pentavalent vanadium. Then add 15 cmof hydrochloric acid diluted 1:1. All flasks is poured 10 cmof diantipyrylmethane solution with a mass fraction of 5%.
In each flask pour water up to the mark and mix.
Measure the optical density of solutions after 20−30 min on a photoelectrocolorimeter with a blue color filter at a wavelength of 390 nm.
A solution of comparison is the solution in the flask containing carbonyl iron, carried through all the stages of analysis, to which add the same reagents as the sample, but not containing titanium.
On the found values of optical density of the solutions and their corresponding titanium concentration to build a calibration curve.
(Changed edition, Rev. N 1, 2).
4. PROCESSING OF THE RESULTS
4.1. Mass fraction of titanium in the percentage found by the calibration schedule.
4.2. Allowable absolute discrepancies in the results of parallel measurements at p = 0.95 does not exceed the values given in the table.
Mass fraction of titanium, % |
The absolute allowable difference, % |
From 0.01 to 0.02 incl. |
0,005 |
SV. 0,2* «0,05 « |
0,008 |
«0,05» 0,10 « |
0,010 |
«To 0.10» to 0.20 « |
0,03 |
«To 0.20» to 0.50 « |
0,04 |
«0,5» 1,0 « |
0,05 |
«1,0» 1,5 « |
0,07 |
_________________
* Consistent with the original. — Note «CODE.
(Changed edition, Rev. N 2).