Typical Equations Used to Predict Moduli of Particulate Composites

APPENDIX A. TYPICAL EQUATIONS USED TO PREDICT MODULI OF PARTICULATE COMPOSITES 

In each case, and refer to Young s moduli for the filled and unfilled resin, respectively, G, and Gp are the corresponding shear moduli, ty is the volume fraction of filler, and S is the relative sedimentation volume of the filler S is defined as the ratio of the apparent to true volume of the filler. In all cases the ratio EJEp may be considered as equivalent to GJGp. 

Filers 1941) (sometimes quoted as the Eilers-Van Dyck equation) 

The value of S is commonly taken to be in the range 1.2 to 1.3, the theoretical value for close-packed uniform spheres being 1.35 (Nielsen, 1967a).  

Many equations for composite moduli can be put in this form. 

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