ISO 6827:1981

Overview

ISO 6827:1981 - Aluminium and aluminium alloys: Determination of titanium content by the diantipyrylmethane photometric method - specifies a laboratory photometric procedure for measuring titanium (Ti) in aluminium and aluminium alloys. The method is applicable to products with titanium contents in the range 0.003 to 0.3 % (m/m). The standard defines principle, reagents, apparatus, sampling guidance, calibration, expression of results and test-report requirements.

Key topics and technical requirements

• Analytical principle: dissolution of the sample, chemical treatment to eliminate interferences (reduction of Fe(III) and V(V) with ascorbic acid in the presence of Cu(II)), formation of a yellow Ti–diantipyrylmethane complex and photometric measurement near 400 nm.
• Working range: suitable for Ti contents from 0.003% to 0.3% (mass); calibration with standard Ti solutions is required.
• Reagents and standards: includes commonly used acids and oxidants (HCl, H2SO4, HNO3, HF, H2O2), KMnO4, CuSO4, ascorbic acid and diantipyrylmethane reagent; preparation of Ti standard solutions (dilution series) and an aluminium compensation solution are specified.
• Apparatus: routine laboratory glassware plus a spectrophotometer (or electrophotometer with suitable filters) calibrated to the absorption maximum of the colored complex.
• Procedure essentials: sample digestion, oxidation, clarification (including treatment for silica residues), color development, measurement after a fixed reaction time (≈30 min), blank/compensation correction, and use of an external calibration curve to calculate Ti mass fraction.
• Reporting: test report must identify the sample, method reference, numerical results and any deviations or unusual observations.

Applications and typical users

• Quality control and chemical analysis in aluminium production and alloy manufacturing.
• Metallurgical and materials testing laboratories verifying Ti content in wrought or cast aluminium products and scrap.
• Inspection and certification bodies ensuring compliance with material specifications.
• R&D labs comparing photometric results with other analytical techniques (AAS, ICP) for method validation.

Practical value and SEO keywords

This ISO method provides a cost-effective, spectrophotometric route for routine titanium assays in aluminium matrices. Keywords: ISO 6827:1981, aluminium titanium determination, diantipyrylmethane photometric method, spectrophotometric titanium analysis, aluminium alloy quality control.

Related standards

ISO 6827 references general laboratory practice for sampling and reporting. Users commonly apply this method alongside standards for aluminium sampling and alternative elemental analysis methods (atomic absorption, ICP-OES) when broader elemental profiling or lower detection limits are required.