Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This is Part 87 of GB/T 223.
This part is developed in accordance with the rules given in GB/T 1.1-2009.
This part was proposed by China Iron and Steel Association.
This part is under the jurisdiction of the National Technical Committee on Iron and Steel of Standardization Administration of China (SAC/TC 183).
Iron, steel and alloy - Determination of calcium and magnesium - Inductively coupled plasma mass spectrometric method
1 Scope
This part of GB/T 223 specifies a method for the determination of the content of calcium and magnesium by inductively coupled plasma mass spectrometric method.
This part is applicable to the determination of calcium contents of mass fraction 0.0002%~0.0035% and magnesium contents of mass fraction 0.0003%~0.05% in iron, steel and alloy.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 6379.1 Accuracy (trueness and precision) of measurement methods and results - Part 1: General principles and definitions (GB/T 6379.1-2004, ISO 5725-1:1994, IDT)
GB/T 6379.2 Accuracy (trueness and precision) of measurement methods and results - Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method (GB/T 6379.2-2004, ISO 5725-2:1994, IDT)
GB/T 6682 Water for analytical laboratory use - Specification and test methods (GB/T 6682-2008, ISO 3696:1987, MOD)
GB/T 20066 Steel and iron - Sampling and preparation of samples for the determination of chemical composition (GB/T 20066-2006; ISO 14284: 1996, IDT)
3 Principle
The test portion is dissolved in a hydrochloric, nitric and hydrofluoric acid mixture. If necessary, use perchloric acid to fume. The diluted sample solution is introduced into an ICP-MS by peristaltic pump and the intensity of the mass spectrum signal from each element is measured simultaneously with the ICP-MS.
The calibration blank and the calibration solution are subjected matrix matching with the major elements in the sample under test and with the acid used for test portion decomposition. The internal standard solution is used to compensate apparatus drift and matrix effect.
4 Reagents
During the analysis, unless otherwise stated, use only high purity reagents containing less than 0.0001% mass fraction of calcium and magnesium or those of equivalent purity and grade 1 water specified in GB/T 6682. If the requirements cannot be met, the acid purification device (5.3) shall be used to purify the reagent.
4.1 Hydrochloric acid, ρ=1.19g/mL.
4.2 Nitric acid, ρ=1.42g/mL.
4.3 Hydrochloric acid, ρ=1.19g/mL.
4.4 Perchloric acid: ρ=1.67g/mL.
4.5 Calcium stock standard solution, 1,000μg/mL
Weigh 2.4972g of calcium carbonate (minimum 99.99% mass fraction) that has been baked at 110°C for 1h and cooled to room temperature in a dryer. Place it in a 400mL beaker, add 100mL of hydrochloric acid (1+1) to dissolve it, cool and transfer the solution to a 1,000mL volumetric flask, dilute to the scale with water and shake well.
This solution contains 1,000μg calcium per 1mL.
4.6 Magnesium stock standard solution, 1,000μg/mL
Weigh 1.6582g of magnesium oxide (minimum 99.99% mass fraction) that has been ignited at 850℃ for 30min and cooled to room temperature in a dryer. Place it in a 400mL beaker, add 100mL of hydrochloric acid (1+1), dissolve it by heating, cool to room temperature and transfer the solution into a 1,000mL volumetric flask, dilute to the scale with water and shake well.
This solution contains 1,000μg magnesium per 1mL.
4.7 Calcium and magnesium mixed standard solution
4.7.1 Calcium and magnesium mixed standard solution: 100μg/mL
Pipette 10mL of the calcium stock standard solution (4.5) and magnesium stock standard solution (4.6) into 100mL volumetric flasks respectively, add 10mL of hydrochloric acid (4.1), dilute to the scale with water and mix well.
This solution contains 100.0μg calcium and magnesium per 1mL.
4.7.2 Calcium and magnesium mixed standard solution, 10μg/mL
Pipette 10mL of calcium and magnesium mixed standard solution (4.7.1) into a 100mL volumetric flask, add 10mL of hydrochloric acid (4.1), dilute to the scale with water and mix well.
This solution contains 10.0μg calcium and magnesium per 1mL.
4.7.3 Calcium and magnesium mixed standard solution, 1μg/mL
Pipette 10mL of calcium and magnesium mixed standard solution (4.7.2) into a 100mL volumetric flask, add 10mL of hydrochloric acid (4.1), dilute to the scale with water and mix well.
This solution contains 1.0μg calcium and magnesium per 1mL.
4.8 Scandium internal standard solution
4.8.1 Scandium stock standard solution, 1,000μg/mL
Weigh 1.5338g of scandium trioxide (minimum 99.99% mass fraction) that has been ignited at 800°C for 1h and cooled to room temperature. Place it in a 400mL beaker, add 100mL of nitric acid (1+1) to dissolve it, and add hydrogen peroxide dropwise until it is completely dissolved. Boil to remove the hydrogen peroxide, cool the solution to room temperature, transfer it into a 1,000mL volumetric flask, add 100mL of nitric acid (1+1), dilute to the scale with water and mix well.
This solution contains 1,000μg scandium per 1mL.
4.8.2 Scandium internal standard solution, 10.0μg/mL
Pipette 10mL of scandium stock standard solution (4.8.1) into a 1,000mL volumetric flask, add 100mL of nitric acid (1+1), dilute to the scale with water and mix well.
This solution contains 10.0μg scandium per 1mL.
4.8.3 Scandium internal standard solution, 1.0μg/mL
Pipette 10mL of scandium internal standard solution (4.8.2) into a 1,000mL volumetric flask, dilute it to the scale with water and mix well.
This solution contains 1.0μg scandium per 1mL.
4.9 Mass calibration standard solution (magnesium, rhodium, indium, cerium, lead and uranium)
10.0μg/L.
4.10 Mass spectrometer cleaning solution
Add about 400mL of water to a 500mL plastic (e.g. polyethylene plastic) bottle, then 15mL of hydrochloric acid (4.1), 5mL of nitric acid (4.2) and 2.5mL of hydrofluoric acid (4.3) and dilute the solution to about 500mL with water.
The mass of acid shall be checked by mass spectrometer scanning before using the acid. If any peak of related elements appears, the acid shall be replaced or purified, and the same element shall be re-checked.
Foreword i 1 Scope 2 Normative references 3 Principle 4 Reagents 5 Apparatus 6 Sampling and preparation of samples 7 Test procedures 8 Calculation of result 9 Precision 10 Test report Annex A (Informative) Possible potential mass spectrometry interference on calcium and magnesium Annex B (Informative) Samples and raw data for precision test
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This is Part 87 of GB/T 223.
This part is developed in accordance with the rules given in GB/T 1.1-2009.
This part was proposed by China Iron and Steel Association.
This part is under the jurisdiction of the National Technical Committee on Iron and Steel of Standardization Administration of China (SAC/TC 183).
Iron, steel and alloy - Determination of calcium and magnesium - Inductively coupled plasma mass spectrometric method
1 Scope
This part of GB/T 223 specifies a method for the determination of the content of calcium and magnesium by inductively coupled plasma mass spectrometric method.
This part is applicable to the determination of calcium contents of mass fraction 0.0002%~0.0035% and magnesium contents of mass fraction 0.0003%~0.05% in iron, steel and alloy.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 6379.1 Accuracy (trueness and precision) of measurement methods and results - Part 1: General principles and definitions (GB/T 6379.1-2004, ISO 5725-1:1994, IDT)
GB/T 6379.2 Accuracy (trueness and precision) of measurement methods and results - Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method (GB/T 6379.2-2004, ISO 5725-2:1994, IDT)
GB/T 6682 Water for analytical laboratory use - Specification and test methods (GB/T 6682-2008, ISO 3696:1987, MOD)
GB/T 12806 Laboratory glassware - One-mark volumetric flasks (GB/T 12806-2011, ISO 1042:1998, NEQ)
GB/T 12808 Laboratory glassware - One-mark pipettes
GB/T 20066 Steel and iron - Sampling and preparation of samples for the determination of chemical composition (GB/T 20066-2006; ISO 14284: 1996, IDT)
3 Principle
The test portion is dissolved in a hydrochloric, nitric and hydrofluoric acid mixture. If necessary, use perchloric acid to fume. The diluted sample solution is introduced into an ICP-MS by peristaltic pump and the intensity of the mass spectrum signal from each element is measured simultaneously with the ICP-MS.
The calibration blank and the calibration solution are subjected matrix matching with the major elements in the sample under test and with the acid used for test portion decomposition. The internal standard solution is used to compensate apparatus drift and matrix effect.
4 Reagents
During the analysis, unless otherwise stated, use only high purity reagents containing less than 0.0001% mass fraction of calcium and magnesium or those of equivalent purity and grade 1 water specified in GB/T 6682. If the requirements cannot be met, the acid purification device (5.3) shall be used to purify the reagent.
4.1 Hydrochloric acid, ρ=1.19g/mL.
4.2 Nitric acid, ρ=1.42g/mL.
4.3 Hydrochloric acid, ρ=1.19g/mL.
4.4 Perchloric acid: ρ=1.67g/mL.
4.5 Calcium stock standard solution, 1,000μg/mL
Weigh 2.4972g of calcium carbonate (minimum 99.99% mass fraction) that has been baked at 110°C for 1h and cooled to room temperature in a dryer. Place it in a 400mL beaker, add 100mL of hydrochloric acid (1+1) to dissolve it, cool and transfer the solution to a 1,000mL volumetric flask, dilute to the scale with water and shake well.
This solution contains 1,000μg calcium per 1mL.
4.6 Magnesium stock standard solution, 1,000μg/mL
Weigh 1.6582g of magnesium oxide (minimum 99.99% mass fraction) that has been ignited at 850℃ for 30min and cooled to room temperature in a dryer. Place it in a 400mL beaker, add 100mL of hydrochloric acid (1+1), dissolve it by heating, cool to room temperature and transfer the solution into a 1,000mL volumetric flask, dilute to the scale with water and shake well.
This solution contains 1,000μg magnesium per 1mL.
4.7 Calcium and magnesium mixed standard solution
4.7.1 Calcium and magnesium mixed standard solution: 100μg/mL
Pipette 10mL of the calcium stock standard solution (4.5) and magnesium stock standard solution (4.6) into 100mL volumetric flasks respectively, add 10mL of hydrochloric acid (4.1), dilute to the scale with water and mix well.
This solution contains 100.0μg calcium and magnesium per 1mL.
4.7.2 Calcium and magnesium mixed standard solution, 10μg/mL
Pipette 10mL of calcium and magnesium mixed standard solution (4.7.1) into a 100mL volumetric flask, add 10mL of hydrochloric acid (4.1), dilute to the scale with water and mix well.
This solution contains 10.0μg calcium and magnesium per 1mL.
4.7.3 Calcium and magnesium mixed standard solution, 1μg/mL
Pipette 10mL of calcium and magnesium mixed standard solution (4.7.2) into a 100mL volumetric flask, add 10mL of hydrochloric acid (4.1), dilute to the scale with water and mix well.
This solution contains 1.0μg calcium and magnesium per 1mL.
4.8 Scandium internal standard solution
4.8.1 Scandium stock standard solution, 1,000μg/mL
Weigh 1.5338g of scandium trioxide (minimum 99.99% mass fraction) that has been ignited at 800°C for 1h and cooled to room temperature. Place it in a 400mL beaker, add 100mL of nitric acid (1+1) to dissolve it, and add hydrogen peroxide dropwise until it is completely dissolved. Boil to remove the hydrogen peroxide, cool the solution to room temperature, transfer it into a 1,000mL volumetric flask, add 100mL of nitric acid (1+1), dilute to the scale with water and mix well.
This solution contains 1,000μg scandium per 1mL.
4.8.2 Scandium internal standard solution, 10.0μg/mL
Pipette 10mL of scandium stock standard solution (4.8.1) into a 1,000mL volumetric flask, add 100mL of nitric acid (1+1), dilute to the scale with water and mix well.
This solution contains 10.0μg scandium per 1mL.
4.8.3 Scandium internal standard solution, 1.0μg/mL
Pipette 10mL of scandium internal standard solution (4.8.2) into a 1,000mL volumetric flask, dilute it to the scale with water and mix well.
This solution contains 1.0μg scandium per 1mL.
4.9 Mass calibration standard solution (magnesium, rhodium, indium, cerium, lead and uranium)
10.0μg/L.
4.10 Mass spectrometer cleaning solution
Add about 400mL of water to a 500mL plastic (e.g. polyethylene plastic) bottle, then 15mL of hydrochloric acid (4.1), 5mL of nitric acid (4.2) and 2.5mL of hydrofluoric acid (4.3) and dilute the solution to about 500mL with water.
The mass of acid shall be checked by mass spectrometer scanning before using the acid. If any peak of related elements appears, the acid shall be replaced or purified, and the same element shall be re-checked.
Contents of GB/T 223.87-2018
Foreword i
1 Scope
2 Normative references
3 Principle
4 Reagents
5 Apparatus
6 Sampling and preparation of samples
7 Test procedures
8 Calculation of result
9 Precision
10 Test report
Annex A (Informative) Possible potential mass spectrometry interference on calcium and magnesium
Annex B (Informative) Samples and raw data for precision test
