Banca de QUALIFICAÇÃO: JACIANA SILVA DE SANTANA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : JACIANA SILVA DE SANTANA
DATA : 02/09/2019
HORA: 14:30
LOCAL: Sala de Vídeoconferência - UFRN
TÍTULO:

 Study of the Behavior of Al2O3-Ni Prepared by Hight Energy Ball Mill.

PALAVRAS-CHAVES:

Composite Al2O3-Ni, sintering for SPS, hight energy mill, powder metallurgy.

PÁGINAS: 91
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Metalurgia de Transformação
ESPECIALIDADE: Metalurgia de Pó
RESUMO:

The search for materials that ofter greater strength and fracture toughness has provided improvements in the compositions of materials for use in cutting tools. The application of composite materials in this type of application offers several advantages due to characteristics improved by the combination of metals and ceramics. The ceramics are superior in their hardness, chemical stability and refractory character, however, the main negative point is the gragility. In order to minimize this factor, several percentages of nickel were evaluated in the alumina ceramic matrix. Microcrystalline Al2O3-Ni powders can be produced by hight energy ball mill, as well as dense structures with better mechanical properties can be obtained by sintering with liquid phase. This work investigates the effect of the percentages of nickel micrometric powders added on the alumina matrix using the SPS sintering method “Spark Plasma Sintering” of the composites. The proportions used were: 0%, 5%, 10% and 20% by mass of nickel (Ni) in a carbon matrix of 5 millimeters in diameter. The powders were ground in a hard metal container with carbide beads in C3HO (H3C-HCOH-CH3) isopropanol solution, using 5:1 mass/ball ratio, where all the composite preparation powders were milled by up to 50 hours. In the 5% nickel pilot assay sample oh the mixture were collected after 2, 10, 20, 30, 40 and 50 hours of milling. The sintering was performed at a temperature of 1350°C, 1500°C and 1650°C by the SPS method for 6 minutes at the respective worked temperatures. The characterization of the starting powders mixtures and the composite contained before and after sintering were analyzed by physical-chemical, microstructural and mechanical tests. In general, the characterization of composites and ceramics powders was obtained through mechanical, physical and tribological tests. 

MEMBROS DA BANCA:
Presidente - 2613355 - FRANCINE ALVES DA COSTA
Interno - 2414250 - MEYSAM MASHHADIKARIMI
Externo à Instituição - ANGELUS GIUSEPPE PEREIRA DA SILVA - UENF
Externa à Instituição - MARIA JOSÉ SANTOS LIMA