Cover Image, Volume 50, Issue 14


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Piezoresistive metal-insulator composites are good candidates as functional materials for tactile sensor applications. Huge electrical resistance variations upon compressive or tensile stress has been achieved in a composite material based on nickel conductive filler in a polydimethylsiloxane (PDMS) insulating matrix. The conduction mechanism, enhanced by the spiky nanostructured morphology of the filler particles inside the composite, is based on a quantum tunneling effect as confirmed by theoretical models. An exhaustive investigation on the mechanical, electrical and thermal properties of the piezoresistive composite is presented by Stefano Stassi and Giancarlo Canavese on page 984.