Effect of ultrasonic vibration on the structure and composition of the interface regions in Ва–W–Ti–O ceramics

A study of Ba–W–Ti–O ceramics has shown that the structure and composition of their interface regions differ from those in the grain bulk owing to the diffusion of tungsten atoms to the grain surface during sintering. They are determined by the conditions of compacting of dry nanopowders (compaction pressure and power of ultrasonic action) and vary in a nonmonotonic way. Increasing the pressure during dry static compacting and exposure to ultrasound result in the formation of a complex structure of fragments and boundaries between them, increase the acoustic density and lead to a decrease in the intergranular boundary thickness to the values that are sometimes comparable to the lattice constant of the boundary material.