ISO 1268-3:2000

Overview

ISO 1268-3:2000 is an international standard established by the International Organization for Standardization (ISO) that defines a consistent method for producing test plates using wet compression moulding of fibre-reinforced plastics (FRP). Part of the ISO 1268 series, this third part focuses specifically on the wet compression moulding technique that ensures reproducible manufacturing of test plates. These plates are used to characterize fibre reinforcements such as mats and fabrics, enabling standardized testing of physical and mechanical properties.

The standard supports quality control and product development by providing detailed procedures, ensuring comparability of test results globally. It includes specifications on materials, apparatus, processing parameters, and validation methods, all tailored for wet compression moulding of fibre-reinforced plastic composites.

Key Topics

• Wet Compression Moulding Process
  A method using heated or ambient flat mould plates that compress resin-impregnated reinforcement materials. This ensures uniform resin flow and curing under controlled pressure to form test plates.

• Materials

  • Reinforcement typically involves textile glass mats or fabrics.
  • Unsaturated polyester resin (UP resin) with adequate viscosity (above 1000 mPa·s) is used, often filled to enhance flow and reduce shrinkage.
  • The inclusion of accelerators, initiators, colorants, and mold release agents is described to optimize curing and handling.

• Plate Dimensions and Reinforcement Content
  Standard plate sizes are circular (300 mm diameter) or square (300 mm x 300 mm) with a recommended thickness of 4 mm.
  Reinforcement content varies with reinforcement type-20% to 40% by mass for mats, and 40% to 60% for fabrics-adjusted based on filler content in the resin.

• Equipment Specifications

  • Moulds with parallel flat plates capable of maintaining thickness uniformity within ±0.3 mm.
  • Presses capable of applying pressures from 1 to 10 bar with adjustable closing speeds to optimize resin flow and cure.

• Procedure and Quality Control
  Detailed steps guide layer preparation, resin calculation, moulding, and trimming.
  Verification procedures include calcination for fiber content, visual inspection for impregnation quality, and thickness measurement to ensure plate uniformity.

• Reporting Requirements
  The standard specifies essential data for documenting plate preparation-materials, equipment, process parameters, plate characteristics, and deviations-to enable reproducibility.

Applications

ISO 1268-3:2000 is essential in industries where fibre-reinforced plastics are utilized and testing of reinforcement characteristics is critical, including:

• Composite Material Research and Development
  Developing new fibre-reinforced plastics with controlled reinforcement properties and resin matrices.

• Quality Control Testing
  Producing standardized test plates for tensile, flexural, impact, and water absorption tests, ensuring consistent product performance evaluation.

• Manufacturing Process Optimization
  Guiding process engineers in replicable wet compression moulding setups for prototype and batch testing.

• Supplier and Material Certification
  Assisting in material characterization and supplier compliance through reproducible sample preparation.

Related Standards

ISO 1268-3:2000 is part of the ISO 1268 series covering various methods to produce fibre-reinforced plastic test plates:

• ISO 1268-1: General Conditions – Provides overarching conditions for all test plate production methods.
• ISO 1268-2: Contact and Spray-Up Moulding – Details alternative manual methods for sample preparation.
• ISO 1268-4: Moulding of Prepregs – Focuses on pre-impregnated reinforcement materials.
• ISO 1268-5: Filament Winding
• ISO 1268-6: Pultrusion Moulding
• ISO 1268-7: Resin Transfer Moulding
• ISO 1268-9: Moulding of Glass Mat Thermoplastics (GMT)
• Part 8 related to compression moulding of sheet moulding compounds (SMC), bulk moulding compounds (BMC), and dough moulding compounds (DMC) is under preparation.

Supporting standards referenced include:

• ISO 62 (Water Absorption Test)
• ISO 178 (Flexural Properties Test)
• ISO 179 (Impact Strength Test)
• ISO 527-4 (Tensile Properties Test)
• ISO 1172 (Calcination methods for textile-glass content)
• ISO 1183 (Density determination methods)
• ISO 2555 (Viscosity measurement via Brookfield method)

Conclusion

ISO 1268-3:2000 offers a comprehensive and standardized approach to producing fibre-reinforced plastic test plates via wet compression moulding. Its focus on reproducibility, material specification, and quality verification empowers manufacturers and researchers to characterize reinforcement performance accurately and consistently. Adherence to this standard facilitates better comparability of test data worldwide, essential for advancing composite material technology and ensuring reliable product development.