Fabrics

A preform out of a fabric?

For load bearing parts one would like to use fabrics. Preforming a fabric is actually less of a challenge than making a preform out of a roving.

To form the shape of the preform a mould is needed. Also in this case the mould is made of polyester or perforated steel. Through the application of air suction the fabric is held in place. By applying a binder the fabric is fixed in the desired form.

Glass fabrics

For glass fabrics we have developed a UV curing binder. This is actually a resin. It is applied through a spraynozzle. For this a paint spraying nozzle can be used. Just so that a atomised stream of resin is formed.

We use 5% (weight) of binder to produce a firm preform.

Although the glassfibre is held in place through air suction a PE film is placed on top of the preform. This will give additional pressure on the fabric so it will even better conform to the contour of the preform mould.  Through the clear film the UV light is passed thus starting the curingprocess.

After 3 seconds of exposure to the UV light the resin cures. The air suction can be removed and the PE film as well.

The preform is ready.

Carbon fibre fabrics

For the production of carbon fibre preforms we have actually 3 different types of binder. First an adaptation of the UV curing binder, secondly a thermoplastic powder and thirdly a thermoplastic binder woven into the carbon-fibre fabric. Which binder is preferred depends on the level of preforming that is desired.

The basis is the same as with glass fibre: a preform mould and air suction.  The latter binders are “cured” with heat and obviously the UV curing binder with UV light.

Application of the UV curing binder is a resin which is applied with a spraynozzle. The powder is also blown on.

We have a limited set of different carbon-fibre fabrics with the thermoplastic binder.