Abnormal Behavior of ZrO[2]-MgO Porous Ceramic Composite under Compression

Abstract

In this work ZrO[2]-MgO porous ceramic composite fine crystalline structure was studied, its microstructure and mechanical properties after sintering at 1600°С. Pores had a bimodal size distribution with the mean sizes of about 30 and 100 [mu]m. It was shown that the introduction of organic pore-forming particles into the initial powder composition of ZrO[2]-MgO allows producing ceramics with a bimodal pore structure, the material strength is mainly determined by microstresses, and in general, such porous ceramics show uncharacteristic behavior under compression, which is confirmed by plot of the Hall-Petch dependence of microstresses on the average crystallite size with the coefficient K=0.38 MPa m{1/2}, corresponding to plastic materials.