J. Helsing, IMPROVED BOUNDS ON THE CONDUCTIVITY OF COMPOSITES BY TRANSLATION IN AVARIATIONAL PRINCIPLE, Journal of applied physics, 74(8), 1993, pp. 5061-5063
The problem of combining different methods of deriving bounds on the c
onductivity of composite materials is addressed. We combine the transl
ation method and the Hashin-Shtrikman variational principle and apply
the combined method to a composite where the two methods, separately,
give bounds that partly improve on each other; an equiaxed polycrystal
. As a result we get a lower bound which improves on all previously kn
own bounds for this composite.