Author/Authors :
Lee، نويسنده , , Jin-Hyon and Hyun، نويسنده , , Kyung-Hoon and Paik، نويسنده , , Ungyu and Jung، نويسنده , , Yeon-Gil and Lee، نويسنده , , Je-Hyun and Lee، نويسنده , , Kee Sung and Lee، نويسنده , , Hee Soo، نويسنده ,
Abstract :
The effect of hydroxyl groups in polyvinyl butyral (PVB) on the microstructure of electrophoretically deposited green bodies for the fabrication of thermal barrier coatings was investigated. Suspensions of yttria-stabilized zirconia (YSZ) particles were prepared with phosphate ester and PVB in a toluene/ethanol mixed solvent. Dispersion properties of YSZ particles were characterized using adsorption isotherms and electrokinetic measurements at two different hydroxyl group contents in PVB. A correlation was made between dispersion characteristics and the microstructure of the electrophoretically deposited green body. A higher hydroxyl value (B-98) resulted in higher adsorption of PVB on YSZ particles compared to a lower hydroxyl value (B-79). The higher adsorption of B-98 resulted in low dynamic mobility of YSZ particulates and led to the formation of a porous green microstructure. The YSZ suspension prepared with B-98 showed a thicker and more porous green microstructure than the suspension prepared with B-79.