Advanced composite materials are one of the main keys to lightweight, energy efficient structures for Next Generation Aircraft. Unfortunately, there is a serious technical and economic barrier to their cost effective application in areas where accuracy is critical, due to the uncontrolled and largely unpredictable distortion which occurs during the moulding stage. There are many factors affecting this phenomenon, but the net result is often several remakes of tooling to attempt to correct for distortion or spring back, a high scrap rate (often over 40%) and costly assembly problems, since composites are elastic and cannot be bent to shape. The purpose of this research project is to develop an analytical method and associated database for predicting distortion phenomena and to create a materials and processing model to ensure that the production moulding process can be specified and controlled to achieve consistent high precision and reduce scrap rates to less than 5%. The overall aim is to reduce time to market for prototypes and production mouldings, with right first time, predictable component accuracy saving typically three to six months lead time. Also to achieve repeatable, high accuracy in series production mouldings to avoid scrap, reduce rework and achieve closer fit of assemblies. The target is to reduce factory floor costs of producing composite parts by at least 30%. (P1 has conducted tests on assembly cost savings which concur with this figure). This will, in turn, make the composites option commercially more viable to other transport sectors and to general industry. Specific objectives are: a) Obtain a scientific understanding of materials and processing factors affecting composite part accuracy b) Quantify the significant parameters, their interactions and control tolerance levels c) To create a prototype knowledge based Finite Element (FE) an package to predict tooling geometry corrections and processing boundaries to achieve accurate complex 3D shapes The project addresses Brite Euram areas 3A.2.2 and 3A.2.5 to reduce lead time and scrap rates by bringing a scientific knowledge based Computer Aided Design/Computer Aided Engineering (CAD/CAE) approach to tooling and component specification. It also addresses areas 2.1 and 2.2 both short and medium terrn priorities. This project is fully supported by the Euromart Consortium. The project brings together several partners from five EEC countries, covering FE software development, prepreg material manufacture, composite tool manufacture, component moulders and users in aerospace, communications and space sector industries. Two research organisations with specific complementary skills in composites numerical analysis and characterisation support the industrial partners.
Funding SchemeCSC - Cost-sharing contracts
KT1 1HN Kingston Upon Thames
581 88 Linkoeping
DE75 7SW Heanor - Derbyshire
7500 AE Enschede