Overview
SIST EN ISO 25239-5:2020 establishes quality and inspection requirements for friction stir welding (FSW) of aluminium and its alloys. Published by SIST in 2020 and identical to EN ISO 25239-5:2020, this international standard provides manufacturers with a structured approach to confirm their capability to produce welded aluminium components of specified quality using FSW. It defines general quality requirements applicable across industries and does not assign requirements to a particular product group. The standard applies to FSW of aluminium but specifically excludes friction stir spot welding, which is covered by the ISO 18785 series.
Key Topics
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Qualification of Personnel
- Specifies that welding operators must be qualified in accordance with ISO 25239-3.
- Inspection and testing personnel should be suitably competent and preferably qualified according to ISO 9712 or equivalent.
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Equipment Requirements
- Emphasizes the use of suitable, well-maintained FSW equipment capable of producing welds that meet acceptance criteria.
- Requires reproducibility testing after equipment installation, repair, or relocation to ensure consistent weld quality.
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Welding Procedure Specifications (WPS)
- Production welding must follow a qualified Welding Procedure Specification.
- Manufacturers are responsible for ensuring correct use and traceability of the WPS.
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Pre-weld and Post-weld Activities
- Includes guidelines for joint preparation, pre-weld cleaning, and temperature control.
- If needed, postweld heat treatments must be documented and compatible with component specification.
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Inspection and Testing
- Covers inspection and testing at several stages: before, during, and after welding.
- Details non-destructive and destructive testing methods including visual, penetrant, radiographic, ultrasonic, tensile, bend, hardness, and fracture tests.
- Provides acceptance criteria for weld imperfections, referencing ISO 6520-1 and others as appropriate.
- Addresses correction of non-conforming weld geometries and repair protocols.
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Identification and Traceability
- Continual identification and traceability of the welds, WPS, and operators throughout the production process is required.
Applications
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Manufacturing of Aluminium Structures
- Supports quality assurance in the FSW of parts for sectors such as transportation (railcar bodies, ship hulls), aerospace, construction, and consumer products.
- Relevant for serial production as well as custom manufacturing where FSW is used for joining aluminium alloys.
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Quality Management Systems
- Provides a framework for welding quality management systems to demonstrate compliance in audits and certifications.
- Helps manufacturers meet customer and regulatory requirements for welded aluminium assemblies.
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Process Improvement and Training
- Encourages best practices in FSW operations, from equipment maintenance to documentation and inspection.
- Supports the training and qualification of welding and inspection staff, crucial for maintaining high production standards.
Related Standards
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ISO 25239 Series: This standard is part of a series covering:
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Inspection and Testing Standards:
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Imperfection Classification:
- ISO 6520-1: Classification of weld geometric imperfections
- ISO 10042: Quality levels for arc-welded joints in aluminium
By following SIST EN ISO 25239-5:2020, manufacturers can systematically ensure the quality and traceability of friction stir welded aluminium products, meeting both industry and customer expectations for safety and performance.