synthesis of advanced zta for orthopedic application by sol-gel method

the demand for ceramic products for orthopedic applications is increasing due to the lowest rate of wear. a fourth-generation ceramic (biolox delta; ceramtec.) consists of 82 wt. % al2o3, 17 wt. % (1.3 yttria stabilized zro2), 0.5 wt. % strontium oxide, and 0.5 wt. % chromium oxide. it has good mechanical properties compared to the other generations of ceramics (biolox forte and pure alumina), which may increase the range of movement and decrease the rate of dislocation. this ceramic composite (delta) has a smaller grain size (0.6 μm) than previous alumina composites (1.8 μm). so, this paper tries to obtain the smallest grain size on the scale of nanometers to improve biolox properties and good distribution for its components. by the sol-gel method, the biolox delta was prepared from the gel precursor and sintering at 1100 °c for 2 h in the oven. the heat-up rate was 5 °c/min. as-obtained particles were characterized before and after sintering temperature using x-ray diffraction (xrd), energy dispersive x-ray analysis (edx), and scanning electron microscopy (sem). the dried powder which was obtained consists of phases, γ-al2o3, θ-al2o3, and δ-al2o3, while zro2 is found as (t + m) zro2 after calcination and the obtained average grain size was (10.94 nm).