Banca de DEFESA: HUGO PLÍNIO DE ANDRADE ALVES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : HUGO PLÍNIO DE ANDRADE ALVES
DATE: 17/08/2020
TIME: 13:00
LOCAL: Sala virtual (Google Meet)
TITLE:

Structural and magnetic properties of the zirconia-magnetic particle and zirconia-graphene ceramic tapes

KEY WORDS:

zirconia, magnetic particles, graphene, tape casting

PAGES: 122
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Cerâmicos
SUMMARY:

The search for improvement in the integration of materials with magnetic advantages in ceramic matrices is an attractive topic since there is a lack of literature. Materials such as magnetic particles and graphene become candidates for improving the magnetic performance of ceramic matrices. In this work, the magnetic particles were produced by the microwave-assisted combustion method to obtain iron oxides. The tape casting technique was used to produce the ceramic tapes. This thesis aims to study the structural and magnetic properties of zirconia-magnetic particles and zirconia-graphene ceramic tapes, mainly after sintered at 1200 ºC. The suspensions of the ceramic materials presented the pseudoplastic behavior, which is recommended for the tape casting technique, verified by the viscosity test. X-ray diffractograms revealed the phases of monoclinic zirconia, tetragonal zirconia, magnetite, and hematite. The presence of graphene in the sintered ceramic tape was confirmed by Raman spectroscopy analysis. The ceramic tapes presented irregular morphologies and grains of different sizes. However, the tape incorporated with graphene has an appropriate amount of pores and agglomerates. The magnetic behavior of the zirconia ceramic tape was affected by the incorporation of materials, magnetic particles (magnetite and hematite), and graphene. The considerable increase in the hematite phase, after sintering, led to a change in the ferrimagnetic order (green tape) to antiferromagnetic order (sintered tape). Graphene, in turn, boosted the ferromagnetic behavior in the sintered tape. Based on these results, ceramic tapes become excellent candidates for technological applications in magnetic devices and carbon-based composite materials.

BANKING MEMBERS:
Externo à Instituição - LISZANDRA FERNANDA ARAÚJO CAMPOS - UFPB
Externo à Instituição - Antonio Carlos Silva da Costa - UFRN
Externo à Instituição - DANIEL ARAÚJO DE MACEDO - UFPB
Interno - 1474380 - MARCIO ASSOLIN CORREA
Presidente - 1149564 - WILSON ACCHAR