کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1475173 | 991110 | 2011 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Sintering behavior and mechanisms of NiO-doped 8 mol% yttria stabilized zirconia Sintering behavior and mechanisms of NiO-doped 8 mol% yttria stabilized zirconia](/preview/png/1475173.png)
Sintering behavior and densification mechanisms of NiO-doped YSZ were investigated by using a dilatometer, combined with XRD, SEM and HRTEM characterization. The solubility of NiO in YSZ is found to be 0.5–1 mol% at 1500 °C by XRD, and TEM reveals that, beyond solubility limit, the undissolved NiO exists in the form of nano and/or micro-sized crystals depending on the doping amount. The sintering model was used to address the enhanced sintering of YSZ as a result of small additions of NiO. Lattice diffusion is examined to be the rate-determining mechanism for the intermediate-stage sintering of both undoped and NiO-doped YSZ. However, the apparent activation energy for densification of YSZ is reduced by ∼70 kJ/mol upon NiO doping. It is concluded that the dissolved NiO contributes to the lowering of the activation energy and therefore the enhanced lattice diffusivity.
Journal: Journal of the European Ceramic Society - Volume 31, Issue 14, November 2011, Pages 2621–2627