Today, advanced composites use either layers of plies impregnated with resin (pre-pregs) to form a laminate, or the use Liquid Composites Moulding (e.g. RTM) of dry textiles. Pre-preg composites give superior mechanical properties due to toughened resins and high fibre content. However, they suffer from high material costs, limited shapeability, complex, expensive and time consuming manufacturing, and limited materials shelf life.
Infusion technologies can overcome these limitations, but are not fully industrialised and rely on costly prototype testing due to the lack of simulation tools.
Current infusion simulation technologies are approximate and only suited to small scale components, based on adaptations of Resin Transfer Moulding simulation. They are not accurate for large, thick and complex aerospace composites, where one sided tooling and vacuum membranes cause complex 3D heat/flow processes.
The INFUCOMP project will develop the full simulation chain from preform design to manufacture (infusion), process/part optimisation and final part defects/mechanical performance prediction with a focus on the infusion step. The project covers all popular Liquid Resin Infusion (LRI) methods currently used in the Aerospace industry. Although focus is on aerospace applications, the work will be very relevant to other industries.
The proposed technologies will allow economical manufacture of high performance, integrated, large scale composite structures, and thus positively contributing to their increased use. Benefits include lower cost, improved performance, greater payloads and fuel/emissions reductions.
The consortium members are from eight different CEC countries, and consists of aircraft and material manufacturers, suppliers, researchers and commercial software specialists. All have a recognised track record in their field.
Virtual prototyping empowers aerospace engineering
EU-funded researchers are developing a simulation chain for the aerospace industry. Beginning with design, it ends with the manufacture of large-scale structures from advanced composite materials.
For the manufacture of large-scale structures and components, the aerospace industry has been using pre-impregnated composite materials, tape laying technologies and autoclave curing. The combination of these technologies allows toughened resins to be uniformly dispersed in a well-controlled fibre system, ensuring strength and fatigue resistance at a high material cost.
To date, the scientists have investigated alternative manufacturing methods based on liquid resin infusion (LRI) technologies, in which the resin is infused only after all dry textiles are assembled. Despite the many advantages, including lower material costs, LRI of large structures requires time-consuming 'trial and error' testing. The EU-funded 'Simulation based solutions for industrial manufacture of large infusion composite parts' (INFUCOMP) project aimed to solve this issue.
To help achieve more rapid manufacturing of high quality parts at a lower cost, the project team has built end-to-end virtual prototyping solutions from preform design to manufacturing. An ambitious set of computer-aided engineering (CAE) tools has been developed that build on existing capabilities of infusion simulation codes. Specifically, INFUCOMP researchers have extended PAM-RTM — an existing simulation software — to provide a simulation chain for LRI composites.
With the INFUCOMP tools covering fabric modelling, drape, assembly, infusion, cost and final performance predictions, costly and time-consuming prototype testing will be avoided. The capabilities of the new CAE tools have been validated on representative aircraft components manufactured using RTI technologies employed by four industrial partners.
The lower cost promised for the manufacture of high performance, large-scale components should contribute positively to the increased use of LRI technologies. More importantly, although the INFUCOMP project focused on aerospace applications, the new CAE tools are expected to be of great value to other industries, including automotive engineering.