Mechanical activation is commonly used as a pre-sintering process in order to enhance the reactivity of materials, reduce the particle size, increase diffusion rates, accelerate the reaction, and lower the sintering temperature. The mechanical activation can affect the final electrical and mechanical characteristics. In this paper we consider the influence of the mechanical activation on the permittivity and the loss tangent. We outline methods for evaluation of these parameters, with emphasis on our coaxial-chamber technique for measurements in the VHF band
