Overview
ISO 3522:2007 - Aluminium and aluminium alloys - Castings - Chemical composition and mechanical properties - establishes standardized rules for specifying chemical composition limits and mechanical properties of aluminium casting alloys. The standard covers designation and temper codes, sampling and testing procedures for separately cast test bars, and rules for determining compliance. It is the fourth edition and includes a technical revision to Table 1 for AlSi9Cu3(Fe).
Key topics and technical requirements
- Chemical composition
- Specifies how alloy compositions are written (Annex A) and lists composition limits in Table 1.
- Analysis is normally by emission spectrometry; sampling should be taken from the melt and cast into a metallic die. Guidance is provided for remelting samples to avoid segregation effects.
- Designation and temper codes
- Defines alloy, temper and casting-process designations (e.g., ISO AC‑AlSi7Mg‑K‑T6) and abbreviations for casting methods (S, K, D, L) and tempers (F, O, T1, T4, T5, T6, T64, T7).
- Mechanical properties and test methods
- Minimum mechanical properties are given for separately cast test bars for sand, chill, investment and pressure die-cast conditions (see Tables 2, 3, 4 and B.1).
- Tensile tests per ISO 6892; Brinell hardness tests per ISO 6506-1. Test-bar geometries referenced to ISO 2378 and ISO 2379.
- Test-piece rules, retests and re-heat-treatment
- Requirements for casting test bars at the same time/from the same melt as production castings; dimensional minima for different casting types.
- Rules for invalid tests, permitted retests (two retests for non‑conformance), and allowed re-heat-treatment cycles (max two) for samples and castings.
- Rounding and compliance
- Clear rounding rules for reporting analysis and mechanical results to determine compliance.
Applications and who uses it
ISO 3522:2007 is used by:
- Foundries and aluminium casting manufacturers - to specify alloys and validate melt quality.
- Quality control and testing laboratories - for sampling, tensile and hardness testing protocols.
- Design and procurement engineers - to select cast aluminium alloys with standardized composition and mechanical property expectations.
- Specification writers and certification bodies - to ensure contractual compliance for cast components in automotive, aerospace, marine and general engineering applications.
Practical benefits include consistent alloy designation, reproducible test methods for aluminium casting alloys, and clear acceptance criteria for chemical and mechanical conformity.
Related standards
- ISO 2378 - Aluminium alloy chill castings - Reference test bar
- ISO 2379 - Aluminium alloy sand castings - Reference test bar
- ISO 6506-1:2005 - Brinell hardness test - Test method
- ISO 6892 - Tensile testing - Ambient temperature method
For full tables of alloy limits, test values and informative comparisons (Annexes B–D), consult the ISO 3522:2007 document.
Open preview (PDF)Aluminium and aluminium alloys — Castings — Chemical composition and mechanical properties