Banca de DEFESA: ODILON HITALO CASTRO OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ODILON HITALO CASTRO OLIVEIRA
DATE: 30/09/2024
TIME: 13:30
LOCAL: meet.google.com/bmn-cetp-jse (videoconferência)
TITLE:

Evaluation of Pack Aluminizing on the Oxidation Resistance of a FeMnSiCrNi Alloy at High Temperature.

KEY WORDS:

FeMnSiCrNi, Pack Aluminization, High-Temperature Oxidation, Austenitic Stainless Steels

PAGES: 77
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Metalurgia Física
SPECIALTY: Corrosão
SUMMARY:

Currently, austenitic stainless steels are produced in large quantities, possessing good mechanical properties, including high toughness and cold workability, with nickel as the primary phase stabilizer. For economic reasons, however, some alloys use manganese as a partial or total substitute for nickel, such as FeMnSiCrNi, which offer relatively low cost, good workability, and ease of processing. Nevertheless, at high temperatures, manganese preferentially reacts with oxygen rather than chromium, preventing the formation of a protective Cr2O3 layer; furthermore, Cr2O3 tends to volatilize at higher temperatures, thus compromising the alloy's oxidation resistance. In contrast to chromium oxide, alumina (Al2O3) is more stable under such conditions; however, the amount of aluminum required to form a protective layer would result in unacceptable mechanical properties. This study evaluated the effect of a coating obtained by pack aluminizing on the oxidation resistance of an FeMnSiCrNi alloy. Cyclic and isothermal oxidation tests were conducted at temperatures of 900 and 1000 °C. At 900 °C, the coating significantly improved the alloy’s oxidation resistance, delaying degradation due to spallation. In the isothermal regime, the aluminized samples showed no spallation; despite manganese diffusion the aluminized coating remained intact. At 1000 °C, however, both aluminized and non-aluminized samples presented loss of mass under both cyclic and isothermal conditions. Compared to other studies, although, the aluminized alloys oxidized at 900 °C achieved significantly better results, given that the tests were conducted under more severe conditions of regime and temperature.

BANKING MEMBERS:
Presidente - 1049564 - ARTUR MARIANO DE SOUSA MALAFAIA
Interna - 2029927 - ROSELI MARINS BALESTRA
Externo à Instituição - FREDERICO AUGUSTO PIRES FERNANDES - UFABC
Externo à Instituição - CARLOS ALBERTO DELLA ROVERE - UFSCAR