Coating of spinel layers on alumina by electrostatic spray deposition (ESD) için kapak resmi
Coating of spinel layers on alumina by electrostatic spray deposition (ESD)
Başlık:
Coating of spinel layers on alumina by electrostatic spray deposition (ESD)
Yazar:
Demirkol, İrem, author.
Yazar Ek Girişi:
Fiziksel Tanımlama:
xiv, 77 leaves: charts;+ 1 computer laser optical disc.
Özet:
MgAl2O4 spinel layer was coated on dense alumina pellets by advantageous ESD among the other deposition methods in terms of providing a simple, inexpensive setup and good control of the layer morphology. The main goals are successfull deposition of spinel layers on alumina pellets by ESD, to investigate the effect of ESD parameters (working distance, flow rate of precursors, applied voltage) on coating microstructure by conducting full factorial design experiments and to determine the best experimental conditions for a porous layer. Besides, MgCr2O4 layer was coated on dense alumina and MgAl2O4 layer was deposited on bisque-fired alumina pellet to extend the scope of the work. Alumina powders were compressed and sintered, respectively to obtain pellets. MgAl2O4 spinel precursor solution was sprayed on the alumina pellets by changing the parameters accordingly the full factorial design. MgAl2O4 and MgCr2O4 solutions were also sprayed on the bisque-fired and the dense alumina pellets with the parameters given the best porous layer. Elemental analysis of the residues obtained after evaporation of the solutions by energy dispersive X-ray spectroscopy (EDX), both unheated and post-heated residual powders of solutions by X-ray diffraction (XRD) and surface morphologies of coated pellets by scanning electron microscopy (SEM-EDS) were analyzed. Spinel layers on alumina pellets were successfully coated by ESD, which could provide variable surface morphologies. The optimum conditions for a porous layer were obtained as working distance of 15 mm, flow rate of 0.25 mL/h and applied voltage of 6 kV in this study. The coatings on the pellets before further heating were amorphous. Post-heating of the pellets were required to obtain crystalline spinel structure.
Yazar Ek Girişi:
Tek Biçim Eser Adı:
Thesis (Master)--İzmir Institute of Technology:Materials Science and Engineering.

İzmir Institute of Technology: Materials Science and Engineering--Thesis (Master)
Elektronik Erişim:
Access to Electronic Versiyon.
Ayırtma: Copies: