Articles
  • Inter-granular phase formation and flexural strength of MgO partially stabilized zirconia by Al2O3 additions
  • Buyoung Kima, Seol Jeona, Chester J. Van Tyneb, Hyun Parkc and Heesoo Leea,*
  • a School of Materials Science and Engineering, Pusan National University, Busan 609-735, Korea b Department of Metallugical and Materials Engineering, Colorado School of Mines, Golden, CO 80401, USA c GCRC-SOP (Global Core Research Center for Ships and Offshore Plants), Pusan National University, Busan 609-735, Korea
Abstract
Phase transformation and inter-granular phase formation of 9 mol% MgO partially stabilized zirconia (Mg-PSZ) according to Al2O3 addition were investigated in terms of crystallography and morphology, and its flexural strength was measured. Sintered bulk specimens of 9 mol% Mg-PSZ ball-milled with Al2O3 (1, 5, 10 mol%) were evaluated by X-ray diffraction, transmission electron microscopy and EDS. Monoclinic phase in Mg-PSZ, which has a larger lattice than that of cubic and tetragonal phases, increased as a function of Al2O3 addition. The apparent density of Mg-PSZ was decreased with increasing Al2O3 addition, and flexural strength was also exibited the lowest value with 10 mol% Al2O3 addition. Mg-rich phase, forsterite (Mg2SiO4), and spinel (MgAl2O4) were observed along grain boundary of Mg-PSZ with Al2O3 additon by TEM-EDS. It was considered that destabilization of Mg-PSZ by Al2O3 addition led to decrease the apparent density, and countinuous intergranular phase formation caused the decrease of flexural strength.

Keywords: Magnesia partially stabilized zirconia (Mg-PSZ), Al2O3 addition, Destabilization, Flexural strength, Inter-granular phase.

This Article

  • 2016; 17(5): 459-463

    Published on May 31, 2016