Microstructure, strain fields and flow stress in deformed metal matrix composites

An experimental study of local orientations around whiskers in deformed metal matrix composites has been used to determine the strain gradients existing in the material following tensile deformation. These strain fields have been represented as arrays of geometrically necessary dislocations, and the material flow stress predicted using a standard dislocation hardening model. Whilst the correlation between this and the measured flow stress is reasonable, the experimentally determined strain gradients are lower by a factor of 5-10 than values obtained in previous estimates made using continuum plasticity finite element models. The local orientations around the whiskers contain a large amount of detailed information about the strain patterns in the material, and a novel approach is made to representing some of this information and to correlating it with microstructural observations. © 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.

INFLUENCE OF MICROSTRUCTURE ON THE TOUGHNESS OF CARBON FIBRE/PLASTIC COMPOSITES.

A preliminary study is presented of the relationship between the microstructural aspects of failure and the fracture energy G//1//C for cracking parallel to the fibres in long-fibre/thermoplastic matrix composites. Fracture energies are measured by a new technique, and fracture surfaces generated by the test are examined by scanning electron microscopy.

INFLUENCE OF MICROSTRUCTURE ON THE TOUGHNESS OF CARBON FIBRE/PLASTIC COMPOSITES.

A preliminary study is presented of the relationship between the microstructural aspects of failure and the fracture energy G//l//C for cracking parallel to the fibres in long-fibre/thermoplastic matrix composites. Fracture energies are measured by a new technique, and fracture surfaces generated by the test are examined by scanning electron microscopy.