Overview
ISO 21339:2023 specifies an inductively coupled plasma atomic emission spectrometric (ICP‑AES) method for the quantitative determination of aluminium (Al) and vanadium (V) in 6Al‑4V titanium alloys. The standard applies to 6Al‑4V grades described in ISO 23515 and covers aluminium in the range 4.70 % to 7.00 % and vanadium 3.00 % to 5.00 % (mass fraction). The procedure uses acid dissolution (nitric + hydrofluoric acids), matrix-matched calibration and optional internal standards for accurate ICP‑AES analysis.
Key topics and requirements
- Scope and applicable range: Targets composition control of 6Al‑4V alloys (Al 4.70–7.00 %, V 3.00–5.00 %).
- Principle: Sample dissolution in HNO3 and HF, dilution, nebulization into ICP and measurement of emission intensities for Al and V (and internal standard if used).
- Reagents and standards: Use analytical-grade reagents and Grade 2 water (ISO 3696). Standard solutions (1 g/L) for Al and V are described; internal standards allowed (indium, cobalt or strontium).
- Apparatus: Class A volumetric glassware (ISO 648/1042); plastic beakers/flasks; ICP‑AES with a hydrofluoric‑acid‑resistant nebulizer. Instrument must be capable of measuring analyte lines and the internal standard (simultaneous or adapted sequential spectrometers).
- Sampling and sample prep: Typical test sample is millings/drillings (≤ 5 mm), dry and clean. Test portion commonly 0.10 g (user may vary if validated). Dissolve with nitric and hydrofluoric acid and dilute to volume.
- Calibration and measurement: Use matrix-matched calibration solutions (includes titanium carrier), perform duplicate determinations under repeatability conditions (single run allowed by agreement), and follow instrument optimization/background correction.
- Quality and reporting: The standard defines expression of results, precision data (inter‑laboratory information included), and test report requirements.
Practical applications and users
ISO 21339:2023 is designed for laboratories and organizations requiring reliable compositional analysis of 6Al‑4V titanium alloy, including:
- Metallurgical and chemical testing laboratories (ICP‑AES labs)
- Aerospace and defense manufacturers (material certification and incoming inspection)
- Medical device and implant producers (alloy verification)
- Metal suppliers and material quality‑control teams
- Certification bodies and conformity assessment labs
Keywords: ISO 21339:2023, 6Al‑4V, titanium alloy analysis, ICP‑AES, aluminium determination, vanadium determination, alloy composition testing, metal quality control.
Related standards
- ISO 23515 - designation of titanium alloys (applies to 6Al‑4V grades)
- ISO 3696 - water for analytical laboratory use
- ISO 648, ISO 1042 - laboratory volumetric glassware requirements
This standard supports accurate, reproducible Al and V measurement in 6Al‑4V using ICP‑AES, enabling consistent material verification across industry laboratories.