Abstract
An analytical method proposed in the preceding paper, has been applied to calculate the effective elastic moduli of composites in which fillers are oriented uniaxially, plane-randomly or space-randomly. The shapes of fillers are considered to be fibres or disks with various aspect ratios. (In them spheres are included as one of the special cases.)
The main results found on the Young's moduli of Glass-Epoxy systems are as follows:
(1) The degree of reinforcement with fibres or disks increases logarithmically with the aspect ratio of these fillers. The“critical aspect ratio”for disks is larger than that for fibres, and generally that ratio for plastic-composites is larger than that for metallic-composites.
(2) In the finite range of aspect ratio, fibres are more effective than disks to increase the Young's moduli in the reinforcing direction, when these fillers are oriented uniaxially. Continuous fibres are almost equally effective as disks with infinite aspect ratio. (These are usually called FRP and layered composite.)
(3) When fillers are oriented space-randomly, in the range of aspect ratio more than 10, disks are more effective than fibres on Young's moduli and Poisson's ratio of composites.
(4) The usefulness of approximate solutions in which interactions among fillers are neglected (the case that the elastic moduli of composites are expressed in linear functions of volume fraction of fillers; 1+δv), should be examined for each shape and for each orientation distribution of fillers.
