Mechanical Strength of Agglomerates

P is the adhesion force between two spheres, 8 the agglomerate porosity, and K the coordination number of the primary particles building the agglomerate. For spherical primary particles K is approximately equal to n/e. 

On this basis, the tensile strength of agglomerates which are stabilized by viscoelasticaDy enhanced van der Waals forces can be estimated according to 

The viscosity and the elasticity both depend on the shear or strain rate y, the temperature Tand the plasticizer content w of the amorphous substance. 

The tensile strength of agglomerates stabilized by low-viscosity liquid bridges can be estimated according to Rumpf (1958) using Eq. 7.16  

Here S is the saturation of the porous agglomerate with liquid (ratio of liquid volume versus total void volume within the agglomerate), C a constant parameter (C = 6 for monosized spheres), y the stuface tension of the liquid, and 0 the liquid-solid contact angle (cf. Schubert (1975, 1979)). 

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