Properties of porous zirconia ceramics fabricated by using various pore-forming agents

The present work proposes a new method for fabrication partially stabilized porous zirconia ceramics using monoclinic zirconia as raw material, yttrium nitrate and magnesium compounds as pore-forming agents and stabilizers. Effects of different pore-forming agents, firing temperatures and firing time on properties of samples were investigated. Thermal decomposition of yttrium nitrate and magnesium compounds creates a large number of pores, and thus porous zirconia ceramics were fabricated. ZrO2 can be partially stabilized by Y2O3 and MgO derived from the precursors. The porous ZrO2 ceramics obtained by using Y(NO3)3·6H2O and 4MgCO3·Mg(OH)2·6H2O as pore-forming agents had relatively high stabilization ratio, uniform pores and high strength. The optimum firing temperature and firing time are 1400 °C and 3 h, and the samples have the stabilization ratio of 45.7%, high cold crushing strength (26 MPa), uniform pores, and apparent porosity is about 40%.