Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : EDS

Characterization of Nb2O5-Ni Coating Prepared by DC Sputtering

Hiyam M. Jedy; Rana A. Anaee; Abdullah A. Abdulkarim

Engineering and Technology Journal, 2021, Volume 39, Issue 4A, Pages 565-572
DOI: 10.30684/etj.v39i4A.1902

The Nb2O5-Ni coating was processed using DC sputtering on structural steel and study characterization of composite coating SEM/EDS inspection indicated clearly perfect incorporation of Nb2O5 within the nickel rich. Increasing in surface roughness and decreasing in average diameters of particles were obtained for coated surface compared with uncoated surface from AFM analysis, in addition, microhardness test and thickness test showed that increasing of the hardness value to 163 HV for Nb2O5 - Ni composite coating compared to 132 HV for uncoated samples, the hardness for Ni coating also increasing to155 HV and the thickness for Nb2O5-Ni composite coatings increased significantly compared to uncoated samples.

Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

Abeer F. Al-Attar; Saad B. H. Farid; Fadhil A. Hashim

Engineering and Technology Journal, 2020, Volume 38, Issue 4A, Pages 491-500
DOI: 10.30684/etj.v38i4A.351

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 ( and it was 0.214( of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.