Influence of Sintering Temperature on Pore Structure and Electrical properties of Technologically Modified MgO-Al2O3 Ceramics

  • Halyna Klym Lviv Polytechnic National University
  • Ivan Hadzaman Drohobych Ivan Franko State Pedagogical University
  • Oleh Shpotyuk Lviv Institute of Materials of Scientific Research Company “Carat”
Keywords: ceramics, porous structure, electrical properties, humidity sensitivity, capillary condensation

Abstract

Technologically modified spinel ceramics are prepared from Al2O3 and 4MgCO3×Mg(OH)2×5H2O powders at 1200, 1300 and 1400 oC. The influence of sintering temperature on porous structure and exploitation properties of obtained humidity-sensitive MgO-Al2O3 ceramics are studied. It is shown that increasing of preparing temperature from 1200 to 1400 oC result in transformation of pore size distribution in ceramics from tri- to bi-modal including the open macro- and mesopores with sizes from tem to hundreds nm and nanopores until to a few nm. The studied ceramic elements with electrical resistances ~ 10-2-102 MОhm are high humidity sensitive in the region of 30-95 % with minimal hysteresis in adsorption-desorption cycles. It is established that increasing of humidity sensitivity in ceramics are related to achievement near to optimum pore size distribution and quantity of pores in the all regions. Prolonged degradation transformation in ceramics at higher temperature and relative humidity result in lose sensitivity up to 40-50 %.

DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5189

Author Biography

Halyna Klym, Lviv Polytechnic National University

Ph.D. in Physics

Department of Specialized Computer Systems,

Institute of Computer Technology, Automatic and Metrolog, Lviv Polytechnic Natioal University

Published
2015-03-25
Section
CERAMICS AND GLASSES