Overview
EN 27627-6:1993 is a European standard developed by CEN that specifies a precise method for the chemical analysis of hardmetals. This part of the standard focuses on the determination of chromium content, ranging from 0.01% to 2% by mass (m/m), using flame atomic absorption spectrometry (FAAS). The procedure is aligned with ISO 7627-6:1985, ensuring international compatibility and consistency in measurements. The standard also references ISO 7627-1 for general requirements on the field of application, sampling, apparatus, and test reports.
This method is crucial for quality control, material characterization, and ensuring compliance in the manufacturing and use of hardmetals, especially in powder metallurgy industries.
Key Topics
- Scope and Application: Targets chromium analysis in hardmetals between 0.01% and 2% content by mass. Suitable for powder metallurgy contexts and chemical analysis of metals.
- Principle: Relies on flame atomic absorption spectrometry to measure chromium by analyzing the absorption of specific wavelengths of light by chromium atoms in a flame.
- Sample Preparation: Requires controlled dissolution of the test portion using potassium pyrosulfate and perchloric acid, followed by dilution with ammonium citrate and addition of hydrogen peroxide. The sample size and preparation details ensure accurate chromium measurement.
- Calibration: Utilizes high purity chromium stock solutions to prepare calibration curves. Solutions are matched in matrix composition to the test samples to minimize interferences, ensuring reliable quantification.
- Measurement Parameters: Absorption is measured at a wavelength of 357.9 nm using N2O flame as the oxidant. Instrument sensitivity and dilution volumes depend on chromium concentration ranges.
- Accuracy and Reporting: Specifies permissible tolerance levels between triplicate measurements and procedures for rounding results. Chromium contents below 0.01% are reported as "
