Collider.material

Description

The material used by the collider.

If material is shared by colliders, it will duplicate the material and assign it to the collider.

// Expose properties in the inspector for easy adjustment.
var dynFriction: float;
var statFriction: float;

var coll: Collider;

function Start() {
    coll = GetComponent.<Collider>();

    coll.material.dynamicFriction = dynFriction;
    coll.material.staticFriction = statFriction;
}

no example available in C#