Overview
ISO 10280:2025 specifies a diantipyrylmethane spectrophotometric method for the determination of titanium in steel and iron. The method applies to titanium mass fractions from 0.002 % to 0.80 %. This second edition updates the original 1991 standard and describes sample preparation, reagents, instrumentation and calculation procedures needed for accurate spectrophotometric measurement of the yellow titanium–diantipyrylmethane complex.
Key topics and technical requirements
- Scope and applicability: Titanium determination in steel and cast iron over the range 0.002–0.80 % (mass fraction).
- Analytical principle: Dissolve the test portion in hydrochloric, nitric and sulphuric acids; fuse insoluble residue with potassium hydrogen sulphate (KHSO4); form a yellow complex with 4,4'-diantipyrylmethane; measure absorbance at about 385 nm.
- Reagents: Uses analytical-grade reagents including HCl, HNO3, H2SO4, HF, KHSO4, Na2CO3, tartaric and ascorbic acids, and diantipyrylmethane. Standard titanium solutions (1 g/L and 50 mg/L) and a high-purity iron reference are specified.
- Apparatus and instrument performance:
- Volumetric glassware class A (ISO 648, ISO 1042).
- Spectrophotometer capable of ~385 nm measurement with wavelength accuracy ±2 nm.
- Repeatability requirement: absorbance repeatable to ±0.003 in the 0.05–0.85 range.
- Sample handling: Test-portion masses depend on expected Ti content (1.00 g for low range, 0.50 g for higher range); sampling and preparation follow ISO 14284.
- Procedure controls: Includes blank tests, fusion and dissolution steps, colour development timing (30–60 min depending on temperature), preparation of calibration curves and duplicate aliquots for coloured and compensating solutions.
- Quality and reporting: Calibration, reagent blanks, precision data and test-report requirements are specified; precision data have been re-evaluated in this edition.
Applications and users
Who benefits from ISO 10280:2025:
- Metallurgical and chemical analysis laboratories conducting routine or certificate testing of steel and cast iron.
- Steelmakers, foundries and quality control teams verifying titanium content for properties like grain refinement and alloy specification.
- Third‑party inspection and certification bodies requiring standardized, traceable methods.
- R&D and materials characterization groups assessing titanium-related alloying effects.
Practical uses include compliance testing, product certification, process control, and failure analysis where accurate titanium quantification is required.
Related standards
- ISO 14284 - Sampling and preparation of samples for chemical composition determination (steel and iron)
- ISO 3696 - Water for analytical laboratory use
- ISO 648 / ISO 1042 - Laboratory glassware (pipettes, volumetric flasks)
ISO 10280:2025 is essential for standardized, reproducible spectrophotometric determination of titanium in iron and steel and integrates with other ISO methods for compositional analysis. Keywords: ISO 10280:2025, titanium determination, diantipyrylmethane spectrophotometric method, titanium in steel, spectrophotometric titanium analysis.
Open preview (PDF)Steel and iron — Determination of titanium content — Diantipyrylmethane spectrophotometric method