Overview
ISO 1268-11:2005 - "Fibre‑reinforced plastics - Methods of producing test plates - Part 11" - defines a standardized method for injection moulding of BMC and other long‑fibre moulding compounds to produce small test plates (60 mm × 60 mm). It specifies two two‑cavity ISO mould types (Type D1 - 2.0 mm thickness, Type D2 - 4.0 mm thickness) and associated moulding practice to ensure reproducible, comparable specimens for mechanical and thermal testing.
Key topics and technical requirements
- Mould geometry: Two‑cavity D1 and D2 ISO moulds producing 60 × 60 mm plates with tight dimensional tolerances; interchangeable cavity plates and gate inserts are recommended.
- Thicknesses: Preferred plate depths - 2.0 ± 0.1 mm (D1) and 4.0 ± 0.1 mm (D2).
- Weld lines: Moulds may accept inserts to study weld‑line effects on mechanical properties (Annex B).
- Machine type: Use reciprocating‑screw injection‑moulding machines with adequate control of process parameters.
- Injection velocity: Typical recommended range ~ 150 ± 50 mm/s for these moulds (unless otherwise specified).
- Hold pressure: Determined empirically by increasing pressure until sink marks/voids are eliminated and flash is minimal; maintain until gate cures.
- Temperature measurement: Procedures for measuring mould cavity temperature (surface readings at several points) and material temperature (free‑shot method with a rapid‑response needle thermometer or validated sensor).
- Moulding best practice: Conditioning of compound before moulding, run‑in to steady state, discard initial mouldings, and cleaning/emptying on material change.
- Instrumentation: Provision for pressure sensor in cavity (used for shrinkage measurement per ISO 2577) and guidelines on heating uniformity and surface finish (polishing direction relative to test loading).
Practical applications and users
This standard is intended for:
- Materials and composite engineers producing standardized test specimens from BMC (bulk moulding compound) and long‑fibre moulding compounds.
- Test laboratories performing mechanical, thermal or shrinkage testing where reproducibility is critical.
- Injection‑moulding tool designers and manufacturers building ISO D1/D2 moulds and gate inserts.
- R&D and quality control teams assessing weld‑line effects, dimensional stability, and comparative material performance.
Benefits include improved comparability of test data, controlled specimen morphology (fibre orientation, cure), and standardized procedures for temperature and pressure measurement.
Related standards
Keywords: ISO 1268-11:2005, fibre‑reinforced plastics, injection moulding, BMC, long‑fibre moulding compounds, small plates, Type D1, Type D2, test specimens, weld lines, moulding conditions.
Open preview (PDF)Fibre-reinforced plastics — Methods of producing test plates — Part 11: Injection moulding of BMC and other long-fibre moulding compounds — Small plates
