Structural and electrical properties of sintered MgTiO3 ceramics

Abstract

Ceramics for electronics play an important role in several industrial sectors. The most common way of producing these ceramics is through sintering processes from powders. The powders can be treated by mechanical activation; during this process they are subjected to grinding and the grain size is reduced. Crystal structure is distorted and changed; in some systems, the process leads to chemical reaction and formation of new compound. In this paper we explain the influence of mechanical activation on sintering kinetics in system MgCO3-TiO2. Mechanical activation of the starting powder mixture was performed by milling during different time intervals within 120 min in a planetary ball mill device with ZrO balls and vessels; ball to powder mass ratio was 40:1. Powders were compacted and sintered isothermally at 1100°C for 180 min. X-ray powder diffraction was used for observing the evolution of magnesium-titanate phase during milling. For specimens synthesized in such manner, microwave dielectric properties were measured, namely dielectric loss (tg δ), specific electric resistance (ρ) and relative dielectric permittivity (εr).