STRUCTURE AND PROPERTIES OF CERAMIC COMPOSITES BASED ON ZRO2

Monodisperse fine powders of high purity obtained by sol-gel method ar e used for production of high technical data ceramics. The fiber reinf orcement is used for hardening of composite materials. It was of inter est to study production possibility of reinforced composite material b ased on ZrO2 obtained by sol-gel method with filler from fibers of par tially stabilized zirconia. ZrO2 powders were obtained by precipitatio n of its hydrated gel from aqueous zirconium oxychloride solution by a mmonium hydroxide followed by thermal treatment. For composite reinfor cement ceramic partially stabilized (8 mole Y2O3) ZrO2 fibers 0.16-0.6 7 mm in length and 5-7 mu m in diameter were used. Content of the fibe rs in composite was 20 wt.%. From powders and their mixtures with fibe rs, the samples were pressed as disks, beams and cylinders, and anneal in air at 1100-1600 degrees C temperature range. The investigation ha s shown that the fibers of partially stabilized zirconia change the co mposite structure, increase the content of tetragonal modification tha t promotes its hardening. Treatment temperature of precursor determine s physical chemical properties of compositions with fibers. Their high specific surface and reaction ability provides a workability of formi ng and sintering processes into strong composite material. The ceramic s was increased by 2.5-3 times as strength after fibrous filler introd uction into ZrO2 hydrogel matrix.