Model for the consolidation of aligned thermoplastic powder impregnated composites

• This paper describes the role of surface energy effects, externally applied pressure, resin flow and fiber bed elasticity on the consolidation of thermoplastic-matrix composites manufactured by the powder impregnation route. Surface energy effects in the spreading of polymer droplets on fiber surfaces are discussed; then a model for the consolidation process is developed, relating the variables mentioned above. Consolidation experiments on powder-impregnated composites of the FIT type (Fibres Impregnees de Thermoplastique) were carried out using a mold attached to a servo-hydraulic testing machine. The model accurately predicts variations in void content during consolidation of carbon fiber/PEEK (CF/PEEK) and carbon fiber/PEI (CF/PEI) laminates. It was found that, at the pressures needed to achieve rapid consolidation, surface energy has a negligible influence on impregnation rate, but its effects on the void topology can be considerable. It was also shown that, when laminates of low void content are required, a minimum pressure is needed to overcome the effect of fiber bed elasticity.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Teknisk mekanik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Applied Mechanics (hsv//eng)

Keyword

Composite materials

Consolidation

Elasticity

Fibers

Flow of fluids

Impregnation

Interfacial energy

Laminates

Mathematical models

Polymers

Pressure effects

Topology

Fiber bed elasticity

Fibres impregnees de thermoplastique

Powder impregnation

Resin flow

Servo hydraulic testing machine

Surface energy effects

Thermoplastic matrix composites

Void content

Thermoplastics

Publication and Content Type

ref (subject category)

art (subject category)