Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE: IHANA GABRIELA CONCEIÇÃO DE JESUS
DATA: 12/06/2024
HORA: 18:00
LOCAL: Sala 5, Complexo Laboratorial Engenharia de Materiais
TÍTULO: Effect of aging time on stress corrosion cracking of super duplex stainless steel UNS S32750
PALAVRAS-CHAVES: Super duplex stainless steel; Thermal aging; Stress corrosion cracking
PÁGINAS: 23
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Metalurgia Física
ESPECIALIDADE: Corrosão
RESUMO:

Super duplex stainless steels are dual-phase alloys containing ferrite and austenite, whose microstructure, corrosion behavior, and mechanical properties are influenced by aging heat treatment. While aging could enhance the mechanical properties of the alloy, deleterious phases can be formed which reduce the stress corrosion cracking and general corrosion performance of the steel if the aging temperature or time are unsuitably chosen. The present study evaluates the isothermal aging effect on the microhardness, electrochemical corrosion, and stress corrosion cracking behavior of the superduplex UNS S32750 alloy. The alloy samples were heated up to 500 ºC for 2 h, 4 h, 8 h, 24 h, 48 h, and 100 h and then they were cooled in water. A stress corrosion cracking test was carried out under the parameters of seawater atmosphere and pressure of 1 MPa of CO 2, at 60 0C for 3 months. The corrosion potential and pitting potential were assessed by electrochemical tests. The results showed the gradual increase of the ferrite phase microhardness as the aging time increased. Aging at 48 and 100 h promoted susceptibility to stress corrosion cracking, evidenced by the increase amount of pitting on the stressed surface and microcracks emerging from the pitting. Furthermore, as the aging time increased, the critical potential for pitting corrosion decreased.

MEMBROS DA BANCA:
Interno - 2080292 - CRISTIANE XAVIER RESENDE
Interno - 1338723 - ROSANE MARIA PESSOA BETANIO OLIVEIRA
Presidente - 358689 - SANDRO GRIZA