Zirconia toughened alumina ceramics are interesting materials for engineering and biomedical applications due to their high strength, hardness, fracture toughness and abrasion resistance, For the same reason final machining is rather costly, making n ear net shape manufacturing technologies such as ceramic injection molding even more attractive to produce ZTA components economically. ZTA containing 10 vol-% of zirconia reinforcement of different yttria content was produced from submicron size powders. Injection molding feedstocks were prepared using a commercial binder system, homogenized at high torque. The rheological properties of the feedstocks were investigated in order to optimize the recipes and predict the molding behavior, Molded test samples - bars and plates -were produced. The debinding process was characterized by thermal analysis, the sintering process was optimized by determination of the sintering kinetics, The sintered samples in this study were characterized by SEM, bending test, hardness test and fracture toughness investigation. To clarify the transformability of zirconia, polished and grinded ZTA samples were analyzed and evaluated by X-ray diffraction, Samples had a homogeneous and defect free microstructure. The bending strength ranged between 350-700 MPa and was noticed to decline gradually as the yttria content increased. The fracture toughness varied from 5.6 to 6.2 MPa·√m at optimum sintering temperatures.
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