Resin Transfer Molding
RTM is a low pressure moulding process, where a mixed resin and catalyst are injected into a closed mould containing a fibre pack or preform. When the resin has cured the mould can be opened and the finished component removed.
A wide range of resin systems can be used including polyester, vinylester, epoxy, phenolic and methyl methacylates etc, combined with pigments and fillers including aluminium trihydrates and calcium carbonates if required.
The fibre pack can be either, glass, carbon, arimid, or a combination of these. There are a large variety of weights and styles commonly available.
The Advantages and Benefits of using RTM:
- Mouldings can be manufactured to close dimensional tolerances
- Components will have good surface finish on both sides
- Selective reinforcement and accurate fibre management is achievable
- Ability to build-in fibre volume fraction loadings up to 65%
- Uniformity of thickness and fibre loading, resulting in uniform shrinkage
- Inserts may be incorporated into mouldings
- Tooling costs comparatively low compared to other manufacturing processes
- Uses only low pressure injection
- Low volatile emission during processing
- Ability to produce near net shape mouldings, reducing material wastage
- Process can be automated, resulting in higher production rates with less scrap
- Ability to mould complex structural and hollow shapes
- Low resultant voidage in moulded components
- Ability to achieve from 0.5mm to 90mm laminate thickness