Conventional abrasive - Chemical analysis of silicon carbide
1 Scope
This standard specifies the determination methods of silicon dioxide, free silicon, free carbon, loss on acid treatment, total carbon, silicon carbide, ferric oxide, aluminium oxide, calcium oxide and magnesium oxide in silicon carbide abrasives and crudes.
This standard is applicable to the determination of chemical composition of abrasives and crudes with silicon carbide content of not less than 95 %.
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 (including any amendments) applies.
GB/T 4676 Abrasive grains - Sampling and splitting (GB/T 4676-2003, ISO 9138: 1993, MOD)
3 Analysis of surface impurities
This clause is applicable to the analysis of surface impurities in the original particle size state of abrasive or after the crude is crushed to a certain particle size.
3.1 Preparation of sample
3.1.1 Abrasives with original particle size state
Take the sample according to GB/T 4676 and divide it to 50 g ~ 60 g, dry it in an oven at (110 ± 5) ℃ for 1 h, take it out, put it in a desiccator, and then cool it for later use.
3.1.2 Crudes
Take statistically representative crudes according to GB/T 4676, crush them until they can completely pass through a 2 mm sieve, mix well, and divide them into 50 g ~ 60 g by quartering. Continue to grind with a steel mortar until all pass through a 355 μm sieve. Attract out the iron brought in during the crushing by a magnet with an attraction of 9.8 N ~ 14.7 N. Mix well, put it into a specimen bag, dry it in the oven at 105 ℃ ~ 110 ℃ for 1 h, take it out, put it into the desiccator, and cool it for later use.
If there are strict requirements for the determination of ferric oxide, separate samples shall be prepared for the determination of ferric oxide according to the following methods: take statistically representative crudes, crush them until they all pass through the 2 mm sieve, mix well, and divide them into 50 g ~ 60 g by quartering. Then grind it by a corundum mortar until all pass through a 500 μm sieve, mix well, and divide it into 20 g ~ 25 g by quartering. Continue to grind it by the corundum mortar until all pass through the 355 μm sieve, mix well, put it into a sample bag, dry it in the oven at 105 ℃ ~ 110 ℃ for 1 h, take it out, put it into the desiccator, and cool it for later use.
3.2 Determination of silicon dioxide
3.2.1 Spectrophotometry
3.2.1.1 Principle
Treat the specimen with sodium chloride - hydrochloric acid - hydrofluoric acid to dissolve silicon dioxide, add ammonium molybdate to generate silicomolybdic heteropoly acid, and then use 1, 2, 4- acid reducing agent to reduce the silicomolybdic heteropoly acid to molybdenum blue, and determine its absorbance at the wavelength of 700 nm.
3.2.1.2 Reagents or materials
Unless otherwise specified, only the recognized analytical reagents and distilled water or deionized water or water with equivalent purity shall be used during the analysis.
3.2.1.2.1 Hydrochloric acid: (1+1), (1+4).
3.2.1.2.2 Aqueous ammonia (1+4): Dilute concentrated aqueous ammonia (with the density of 0.90 g/cm3) with water at a volume ratio of 1:4 and it shall be freshly prepared.
3.2.1.2.3 Hydrofluoric acid: (1+1).
3.2.1.2.4 Sodium chloride solution (10%).
Foreword i
1 Scope
2 Normative references
3 Analysis of surface impurities
3.1 Preparation of sample
3.2 Determination of silicon dioxide
3.3 Determination of free silicon
3.4 Determination of free carbon
3.5 Determination of loss on acid treatment (LAT)
3.6 Determination of silicon carbide
3.7 Determination of ferric oxide
3.8 Determination of aluminium oxide
3.9 Determination of calcium oxide and magnesium oxide
3.10 Determination of ferric oxide, aluminium oxide, calcium oxide and magnesium oxide by inductively coupled plasma-atomic emission spectrometry (ICP-AES)
4 Determination of silicon carbide in abrasives and crudes (indirect method)
4.1 Principle
4.2 Preparation of sample
4.3 Determination of total carbon
4.4 Determination of free carbon
4.5 Test data processing
4.6 Allowable error
5 Other methods of analysis
6 Test report
Annex A (Informative) Structural changes between this standard and ISO 9286: 1997
Conventional abrasive - Chemical analysis of silicon carbide
1 Scope
This standard specifies the determination methods of silicon dioxide, free silicon, free carbon, loss on acid treatment, total carbon, silicon carbide, ferric oxide, aluminium oxide, calcium oxide and magnesium oxide in silicon carbide abrasives and crudes.
This standard is applicable to the determination of chemical composition of abrasives and crudes with silicon carbide content of not less than 95 %.
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 (including any amendments) applies.
GB/T 4676 Abrasive grains - Sampling and splitting (GB/T 4676-2003, ISO 9138: 1993, MOD)
3 Analysis of surface impurities
This clause is applicable to the analysis of surface impurities in the original particle size state of abrasive or after the crude is crushed to a certain particle size.
3.1 Preparation of sample
3.1.1 Abrasives with original particle size state
Take the sample according to GB/T 4676 and divide it to 50 g ~ 60 g, dry it in an oven at (110 ± 5) ℃ for 1 h, take it out, put it in a desiccator, and then cool it for later use.
3.1.2 Crudes
Take statistically representative crudes according to GB/T 4676, crush them until they can completely pass through a 2 mm sieve, mix well, and divide them into 50 g ~ 60 g by quartering. Continue to grind with a steel mortar until all pass through a 355 μm sieve. Attract out the iron brought in during the crushing by a magnet with an attraction of 9.8 N ~ 14.7 N. Mix well, put it into a specimen bag, dry it in the oven at 105 ℃ ~ 110 ℃ for 1 h, take it out, put it into the desiccator, and cool it for later use.
If there are strict requirements for the determination of ferric oxide, separate samples shall be prepared for the determination of ferric oxide according to the following methods: take statistically representative crudes, crush them until they all pass through the 2 mm sieve, mix well, and divide them into 50 g ~ 60 g by quartering. Then grind it by a corundum mortar until all pass through a 500 μm sieve, mix well, and divide it into 20 g ~ 25 g by quartering. Continue to grind it by the corundum mortar until all pass through the 355 μm sieve, mix well, put it into a sample bag, dry it in the oven at 105 ℃ ~ 110 ℃ for 1 h, take it out, put it into the desiccator, and cool it for later use.
3.2 Determination of silicon dioxide
3.2.1 Spectrophotometry
3.2.1.1 Principle
Treat the specimen with sodium chloride - hydrochloric acid - hydrofluoric acid to dissolve silicon dioxide, add ammonium molybdate to generate silicomolybdic heteropoly acid, and then use 1, 2, 4- acid reducing agent to reduce the silicomolybdic heteropoly acid to molybdenum blue, and determine its absorbance at the wavelength of 700 nm.
3.2.1.2 Reagents or materials
Unless otherwise specified, only the recognized analytical reagents and distilled water or deionized water or water with equivalent purity shall be used during the analysis.
3.2.1.2.1 Hydrochloric acid: (1+1), (1+4).
3.2.1.2.2 Aqueous ammonia (1+4): Dilute concentrated aqueous ammonia (with the density of 0.90 g/cm3) with water at a volume ratio of 1:4 and it shall be freshly prepared.
3.2.1.2.3 Hydrofluoric acid: (1+1).
3.2.1.2.4 Sodium chloride solution (10%).
Contents of GB/T 3045-2017
Foreword i
1 Scope
2 Normative references
3 Analysis of surface impurities
3.1 Preparation of sample
3.2 Determination of silicon dioxide
3.3 Determination of free silicon
3.4 Determination of free carbon
3.5 Determination of loss on acid treatment (LAT)
3.6 Determination of silicon carbide
3.7 Determination of ferric oxide
3.8 Determination of aluminium oxide
3.9 Determination of calcium oxide and magnesium oxide
3.10 Determination of ferric oxide, aluminium oxide, calcium oxide and magnesium oxide by inductively coupled plasma-atomic emission spectrometry (ICP-AES)
4 Determination of silicon carbide in abrasives and crudes (indirect method)
4.1 Principle
4.2 Preparation of sample
4.3 Determination of total carbon
4.4 Determination of free carbon
4.5 Test data processing
4.6 Allowable error
5 Other methods of analysis
6 Test report
Annex A (Informative) Structural changes between this standard and ISO 9286: 1997
