Banca de QUALIFICAÇÃO: PEDRO LUCAS GOMES DE SOUZA SILVEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : PEDRO LUCAS GOMES DE SOUZA SILVEIRA
DATE: 19/05/2026
TIME: 09:00
LOCAL: Laboratório de Tribologia da UFRN
TITLE:

Effect of in-situ and ex-situ hydrogen embrittlement on the tribological behavior of SAE 1045, AISI 304, and AISI 316

KEY WORDS:

Hydrogen Embrittlement, tribology, ex-situ, in-situ

PAGES: 48
BIG AREA: Engenharias
AREA: Engenharia Mecânica
SUMMARY:

This work addresses hydrogen as a strategic energy vector for global decarbonization and the technical challenge of hydrogen embrittlement in metallic systems. While scientific literature widely explores the degradation of bulk mechanical properties, such as loss of ductility, a significant gap exists in understanding how this phenomenon affects surface integrity in components operating under contact and sliding conditions. This dissertation aims to comparatively analyze variations in friction coefficient, wear rate, and material removal mechanisms of SAE 1045, AISI 304, and AISI 316 alloys. The investigation covers natural exposure, ex-situ electrolytic charging, and in-situ gaseous atmosphere conditions. The methodology employs pin-on-disk tests associated with contact profilometry and scanning electron microscopy characterization. The analysis reveals that SAE 1045 carbon steel suffers severe surface degradation, with a 68% increase in the average friction coefficient and a transition to a severe delamination mechanism. In contrast, austenitic stainless steels exhibit macroscopic stability, as hydrogen catalyzes strain-induced martensitic transformation, generating surface hardening that limits severe adhesion. The AISI 316 alloy stands out for its more stable and resilient response among the tested materials. The research concludes that tribological vulnerability is governed by microstructure, in which face-centered cubic structure matrices ensure greater operational safety for hydrogen infrastructure.

COMMITTEE MEMBERS:
Presidente - 1481705 - SALETE MARTINS ALVES
Interno - 1938946 - NICOLAU APOENA CASTRO
Externo ao Programa - 1960421 - FRANCISCO DE ASSIS DA SILVA MOTA - UFRN