Dear Shubrajit Bhaumik, often the added particles, tubes or wires represent reinforcements for the structure (for brittle materials like ceramics and concrete they are supposed to improve the tensile load properties of the Composite) and are harder, showing higher strength a.s.o. than the mosten weaker matrix material. Viewing These Composites as braking pats or grind Stones, depending on the orientation, it is to be expected that friction properties are increased as Long as wires and tubes are not parallel to the Motion direction. I can imagine that for protruding wires and tubes shear modulus and fracture toughness could Show some functional Impact on friction properties. Otherwise (for particles e.g.) more the embedding / Interface properties (particle break-out) and the volume Content will be important.
First of all one should be clear what type of friction, one is talking about. One should also emphasize that the friction is a dissipative phenomenon therefore it has no direct connection with elasticity properties.However , If we are talking about the dry friction between two surfaces in contact then the surface roughness enhanced by the inclusion of the nano-metric substances may be very important if they are out of hard brittle materials such as ''High Young modulus having critical Poisson ratio of 1/2- that means it is incompressible'' preferentially having sharp corners and edges.
No! if we are talking about their effects on the internal friction associated with the damping capacity of the matrix under the dynamics structural loading the answer to your question would be very complicated in nature. But it is clearly they lower the fracture toughness if they have sharp corners and edges, which act as stress risers under the cyclic loading ''fatigue' as well as under the applied steady loading ''fracture''.