ISO 8605:2024

Overview - ISO 8605:2024 (Sheet moulding compound, SMC)

ISO 8605:2024 defines requirements and specifications for sheet moulding compound (SMC) used to produce composite parts by hot moulding. This third edition updates and broadens the 2001 version: it adds fibre type and shrinkage codes, a formal designation system, expanded test properties, and guidance on sampling position. The standard covers SMC reinforced mainly with glass fibres (GF) or carbon fibres (CF) but is also applicable to other fibre types (for example, natural fibres). Typical SMC thicknesses are generally between 1 mm and 25 mm.

Key topics and technical requirements

• Scope & definitions: Clear definitions for SMC and related terms used in composite manufacture and testing.
• Classification:
  • By composition (resin/matrix, reinforcement, fillers, additives, mode of reinforcement).
  • By shrinkage behaviour (general-purpose, low-shrinkage, low-profile, Class A).
• Resin types: Unsaturated polyester (UP), epoxy (EP), polyurethane (PU), vinyl ester (VE), phenolic (P) - referenced to relevant resin standards.
• Properties and tests:
  • Properties to describe SMC for acceptance (physical, chemical, appearance).
  • Properties for moulded specimens (mechanical, physical, electrical).
  • References to established test methods for tensile, flexural, impact, density, cure, shrinkage, moisture uptake and electrical characteristics.
• Sampling and conditioning: Procedures for representative sampling and conditioning of SMC before testing.
• Shelf life, packing, packaging and labelling: Requirements to support traceability, storage and transport.
• Designation and documentation: Standardized naming and documentation of SMC grades for procurement and quality control.

Practical applications and who uses ISO 8605:2024

ISO 8605:2024 is intended for organizations involved in the manufacture, specification, testing and procurement of SMC for composite parts produced by hot moulding. Typical users include:

• SMC manufacturers and formulators (material development and quality control)
• Automotive and transportation OEMs (body panels, structural components)
• Electrical and electronics manufacturers (insulating housings, enclosures)
• Aerospace, marine and consumer-goods designers specifying composite materials
• Testing laboratories and certification bodies conducting acceptance and performance tests
• Purchasing and compliance teams using standardized designations and test criteria

Adoption of ISO 8605 helps ensure consistent material properties, reliable production outcomes and clearer supplier specifications for SMC-based composite parts.

Related standards (examples)

ISO 8605 references several established test and material standards, including:

• ISO 527-4 (tensile properties of fibre-reinforced composites)
• ISO 12115 (flowability, maturation and shelf life of thermosetting moulding compounds)
• ISO 14125 (flexural properties)
• ISO 2577 / EN 1842 (shrinkage determination)
• IEC standards for electrical and flammability testing

Keywords: ISO 8605:2024, sheet moulding compound, SMC requirements, fibre-reinforced plastics, glass fibre SMC, carbon fibre SMC, composite parts, hot moulding.