Electrophoretic deposition of ZrO2-Y2O3: a bi-component study concerning self-assemblies

Author(s)

Castro, Ricardo H. R. ^[1] ; Kodama, Paulo K. ^[1] ; Gouvea, Douglas ^[2] ; Muccillo, R. ^[3]

Affiliation

^[1] FEI Univ Ctr, CDMat Dept Mat Engn, BR-09850901 Sao Bernardo Do Campo, SP - Brazil

^[2] Univ Sao Paulo, Dept Met & Mat Engn, Escola Politecn, BR-05508900 Sao Paulo - Brazil

^[3] Ctr Multidisciplinar Desenvolvimento Mat Ceram, CCTM, IPEN CNEN SP, BR-05422970 Sao Paulo - Brazil

• Document type: Journal article
• Source: Journal of Materials Science; v. 44, n. 7, p. 1851-1857, APR 2009.
• Web of Science Citations: 6

Abstract

There are many industrial advantages of using mechanical multi-oxides mixtures to obtain ceramic parts by electrophoretic deposition (EPD). This is mainly because one could avoid complex chemical synthesis routes to achieve a desirable composition. However, EPD of these suspensions is not an easy task as well since many different surfaces are present, leading to unexpected suspension behavior. The particles surface potentials and interactions can, however, be predicted by an extension of the DLVO theory. Using this theory, one can control the suspension properties and particles distribution. The objective of this work was to apply the colloidal chemistry theories to promote the formation of a heterocoagulation between ZrO(2) and Y(2)O(3) particles in ethanol suspension to achieve a suitable condition for EPD. After identifying a condition where those particles had opposite surface charges and adequate relative sizes, heterocoagulation was observed at operational pH 7.5, generating an organized agglomerate with ZrO(2) particles surrounding Y(2)O(3), with a net zeta potential of -16.6 mV. Since the agglomerates were stable, EPD could be carried out and homogeneous deposits were obtained. The deposited bodies were sintered at 1600 A degrees C for 4 h and partially stabilized ZrO(2) could be obtained without traces of Y(2)O(3) second phases. (AU)

• FAPESP's process: 05/53241-9 - Study of intergranular phenomena in ceramic materials
• Grantee: Reginaldo Muccillo
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 05/55335-0 - Sintering of crystalline materials
• Grantee: Ricardo Hauch Ribeiro de Castro
• Support Opportunities: Research Grants - Young Investigators Grants