Overview
ISO 9286:2021 - "Abrasive grains and crude - Chemical analysis of silicon carbide" specifies standardized methods for the chemical analysis of silicon‑carbide (SiC) abrasive grains and crude. The document focuses on determining surface impurities of abrasive grains and the SiC content of crushed crude when the silicon carbide fraction is greater than 95% (mass fraction). This second edition (2021) updates sampling, sample preparation and multiple analytical techniques for reliable quality control and material characterisation.
Key topics and technical requirements
- Scope and applicability: Analysis applies to SiC abrasive grains and crudes; crude analysis limited to SiC content >95% (mass fraction).
- Sampling and sample splitting: Sampling shall follow ISO 9138 (Abrasive grains - Sampling and splitting) to ensure representative test portions.
- Sample preparation: Drying at (110 ± 5) °C until constant mass; specific crushing and sieving steps for fine, coarse and crude samples (progressive reduction to specified grain sizes; corrections if steel mortar introduces iron contamination).
- Surface impurity analyses: Procedures for determining surface carbon (Csurf/free), silicon dioxide (SiO2 surf) and surface silicon (Sisurf) are included.
- Analytical methods referenced:
- Gravimetric and infrared (IR) methods for carbon determination
- HF/KF dissolving reactions and hydrofluoric acid loss tests for SiO2
- Molybdenum blue spectrophotometry for phosphate-type determinations
- Hydrogen gas volumetric and silver displacement methods for surface silicon
- Atomic absorption spectrometry (AAS) and inductively coupled plasma (ICP) for surface metals (Fe, Al, Ca, Mg)
- Loss on acid treatment (LAT) and calculations: Methods to calculate residual SiC from LAT results, analysed impurities and carbon measures.
- Reporting: Requirements for test reports and expression of results are specified.
Practical applications
- Quality control and specification verification for SiC abrasive manufacturers, suppliers and processing mills.
- Incoming material inspection in industries using SiC abrasives (grinding wheels, coated abrasives, metallurgical applications).
- Laboratory testing protocols for materials testing labs, R&D groups developing abrasive products and certification bodies.
- Procurement and compliance checks where accurate SiC content, surface contamination, and metal impurity levels impact product performance.
Who should use ISO 9286:2021
- Abrasive producers, quality managers, analytical chemists, test laboratories, and purchasing/specification engineers who require standardized chemical analysis of silicon carbide and reproducible impurity data.
Related standards
- ISO 9138 - Abrasive grains: sampling and splitting (normative reference used by ISO 9286)
- Other ISO standards on abrasive testing and grain classification (refer to ISO/TC 29 publications)
Using ISO 9286:2021 helps ensure consistent, comparable chemical data for silicon carbide abrasives - supporting product quality, process control and regulatory compliance.
