Overview
ISO/ASTM 52948:2026 is an international standard developed by ISO and ASTM that specifies a comprehensive classification system for imperfections in metallic parts produced by additive manufacturing using powder bed fusion (PBF). This includes both laser beam powder bed fusion (PBF-LB) and electron beam powder bed fusion (PBF-EB) processes. The standard addresses the most probable causes of various imperfections and provides illustrative examples, enhancing understanding and communication about quality issues in additive manufacturing of metals.
While it offers an in-depth categorization of imperfections and their causes, ISO/ASTM 52948:2026 does not specify acceptance criteria or quantitative scales for imperfections. Instead, it serves as a foundational reference for quality control, inspection, and process optimization in the metal additive manufacturing (AM) industry.
Key Topics
- Additive manufacturing imperfections: The document details types of imperfections that may occur in PBF processes, offering terminology and standardized descriptions.
- Classification of imperfections: Six main classes are defined:
- Cracks
- Porosity
- Inclusions
- Lack of fusion
- Shape, dimensional, and surface imperfections
- Other imperfection types
- Probable causes: Each imperfection is linked to likely causes in the manufacturing process, supporting root cause analysis and quality improvement.
- Illustrations and examples: Visual references and diagrams aid in the identification and understanding of imperfections.
- Terminology and definitions: The standard aligns with established vocabularies, ensuring consistent language in communication and reporting.
Applications
ISO/ASTM 52948:2026 is an essential tool for organizations and professionals involved in the additive manufacturing of metallic components using powder bed fusion technologies. Key practical applications include:
- Quality control and inspection: Enables manufacturers to identify, categorize, and trace imperfections, improving inspection processes and non-destructive testing (NDT).
- Process optimization: By linking imperfections to probable causes, the standard helps engineers and operators adjust process parameters and maintenance protocols to minimize defects.
- Training and education: The standardized classification supports operator training and enhances understanding among engineers, technicians, and quality assurance teams.
- Communication and reporting: Establishes a common language that facilitates clearer communication between suppliers, customers, and regulators regarding the quality of additive manufactured metal parts.
- Foundation for acceptance criteria development: While the standard does not set acceptance limits, it is a valuable basis for developing internal or customer-specific criteria.
- R&D and innovation: Supports research in defect analysis and the development of new detection technologies and quality improvement methods for additive manufacturing.
Related Standards
Organizations implementing ISO/ASTM 52948:2026 may benefit from familiarity with related standards and guidelines, including:
- ISO/ASTM 52900 - Additive manufacturing – General principles – Fundamentals and vocabulary
- ISO 3252 - Powder metallurgy – Vocabulary
- ASTM B243 - Standard Terminology of Powder Metallurgy
- ISO/ASTM TR 52905 - Guidelines for non-destructive testing of additively manufactured metal parts
- ASTM E3166 - Guidance on non-destructive testing for additively manufactured parts
- ISO/ASTM 52911-1 - Technical considerations for post-processing and minimization of cracks and other defects
Practical Value
By following ISO/ASTM 52948:2026, manufacturers and quality professionals gain a structured approach to identifying and understanding imperfections in PBF additive manufacturing of metals. This enhances product reliability, supports compliance with customer and regulatory requirements, and drives continuous improvement throughout the additive manufacturing process.
Keywords: additive manufacturing, powder bed fusion, metallic parts, imperfections, PBF-LB, PBF-EB, defect classification, ISO, ASTM, process optimization, quality control, non-destructive testing, metal AM standards.