EN ISO 4829-2:2016 PDF

Overview

EN ISO 4829-2:2016 (CEN adoption of ISO 4829-2:2016) specifies a laboratory spectrophotometric method - the reduced molybdosilicate method - for the determination of total silicon in steels. It is intended for silicon mass fractions in the narrow range 0.01 % to 0.05 %. The standard defines the principle, required reagents and apparatus, sample dissolution and treatment, color development, spectrophotometric measurement and expression of results.

Key Topics

• Scope and applicability: Total silicon determination in steels with Si between 0.01 % and 0.05 % (mass fraction).
• Analytical principle: Dissolution of the test portion (acid attack), fusion of acid‑insoluble residue, formation of an oxidized molybdosilicate complex and selective chemical reduction to a blue complex measured spectrophotometrically (≈810 nm).
• Interference control: Use of oxalic acid and controlled sulphuric acid concentration to prevent interference from elements such as phosphorus, arsenic and vanadium.
• Reagents and contamination control: Use of analytical-grade reagents and ISO 3696 Grade 2 water (ion-exchange demineralized water is not permitted due to colloidal silica risk). Freshly prepared solutions and storage in polypropylene or PTFE containers are recommended to avoid contamination.
• Equipment and glassware: Standard laboratory volumetric apparatus (referenced ISO glassware standards) and spectrophotometer suitable for the specified wavelength.
• Calibration and results: Preparation of silicon standards and calibration curve procedures, plus instructions for expressing results and reporting. Precision and interlaboratory information are included in the standard.

Applications

• Quality control and acceptance testing of steel products where low silicon levels must be monitored (e.g., electrical steels, specialty alloys).
• Chemical analysis laboratories in steel mills and third‑party testing labs performing composition verification for specifications and certifications.
• R&D and process control teams monitoring melt chemistry, raw material qualification, and trace-level silicon effects on properties.
• Failure analysis and metallurgical investigations where accurate low-level silicon data are required.

Who Should Use This Standard

• Metallurgical and analytical chemists
• Steelworks laboratory personnel and quality managers
• Third‑party testing and certification bodies
• Material engineers and researchers working with low‑silicon steels

Related Standards

• EN ISO 4829-1 / ISO 4829-1 - covers higher silicon contents (0.05 % to 1.0 %)
• Normative references cited in the document: ISO 648, ISO 1042, ISO 3696, ISO 14284
• EN 24829-2:1990 - the earlier version superseded by EN ISO 4829-2:2016

Keywords: EN ISO 4829-2:2016, silicon determination, reduced molybdosilicate spectrophotometric method, steel analysis, spectrophotometry, silicon 0.01–0.05%.