France-Australia Technical Arrangement TA 1/99 - Work Package 2: Ab Initio Estimation of Composite Properties
Abstract
Substantial savings could be made in the cost of airworthiness certification of composite aircraft structure if material properties could be predicted solely on the basis of the properties of the constituent fibres and resin. The feasibility of this approach was tested by surveying the literature on the prediction of compression strength. The literature is extensive and indicates that the compression failure process is well understood. The critical factors controlling compression behaviour are the shear stiffness and strength of the composite, not just the resin alone, and misalignment between the load bearing fibres and the loading axis. Relations do exist that characterise the key failure features, including compression strength, however all of these models require some data that must be obtained by testing the composite. In particular the shear stress/shear strain behaviour of resins changes in the presence of fibres so this must be measured experimentally. Gross and local fibre orientation must also be measured. It was concluded that the prediction of compression strength on the basis of fibre and resin properties alone awaits substantial improvements in understanding of the effect of fibres on the shear behaviour of resins and techniques to quantify fibre misalignment.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2005
- Accession Number
- ADA438069
Entities
People
- Paul J. Callus
Organizations
- Defence Science and Technology Group