Banca de QUALIFICAÇÃO: ANDRÉ BARONI JERMOLOVICIUS

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : ANDRÉ BARONI JERMOLOVICIUS
DATA : 25/11/2020
HORA: 14:00
LOCAL: por participação remota: https://meet.google.com/bto-whmc-dsh
TÍTULO:

EFFECTS OF COMPOSITION, TEMPERATURE AND TIME OF SINTERING WITH MICROWAVES ON THE MICROSTRUCTURE AND PROPERTIES OF A TRANSLUCENT PORCELAIN

PÁGINAS: 98
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Cerâmicos
RESUMO:

The results of a study on hybrid sintering with microwaves of translucent porcelains are presented. The objective of this study is to establish a relationship between the a) proportion between the levels of white kaolin and potassium feldspar, b) sintering temperature, c) holding time at the sintering temperature, and the properties of the sintered sample: bulk density, water absorption, light transmittance, and dielectric constant. The tests were carried out with three porcelain compositions with different contents of kaolin (40, 45 and 49%) and feldspar (39, 34 and 30%), beside 17% of quartz, 3% of wollastonite, and 1% of bentonite. Specimens formed by pressing were sintered in a microwave furnace with a firing chamber with a silicon carbide susceptor, at three temperatures (1200, 1240 and 1260 °C). Two heating procedures until the sintering temperature were tested: a) single ramp employing full power of the magnetrons, and b) with five short ramps relative to four intermediate heating levels. For comparison to microwave heating, firings in a conventional electric furnace were carried out. As a result, it was observed that microwave sintering produced porcelain with a higher density and less water absorption, compared to conventional sintering. It was also observed that the intermediate ramps during heating led to better results. Due to the initial results, extreme limits were established for the application of a central composite design (CCD) to be performed to establish empirical equations, via CCD, to relate the investigated properties with the composition of translucent porcelain. For this purpose, in addition to microwave sintering, physical characterization and microstructural analyzes (X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy) of the sintered samples will be carried out.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 1948454 - VANIA TROMBINI HERNANDES
Membro Titular - Examinador(a) Externo à Instituição - ROMUALDO RODRIGUES MENEZES - UFCG
Membro Titular - Examinador(a) Externo à Instituição - EDUARDO VICTOR DOS SANTOS POUZADA - IMT
Membro Suplente - Examinador(a) Interno ao Programa - 1997753 - LUIZ FERNANDO GRESPAN SETZ
Membro Suplente - Examinador(a) Interno ao Programa - 2604128 - ALEXANDRE JOSE DE CASTRO LANFREDI
Membro Suplente - Examinador(a) Externo à Instituição - ROBERTO NASSER JUNIOR - UNIFESP