Banca de QUALIFICAÇÃO: Rodrigo de Oliveira França

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : Rodrigo de Oliveira França
DATE: 04/11/2025
TIME: 10:30
LOCAL: Anfiteatro do Campus Santo Antonio - UFSJ
TITLE:

High-Temperature Oxidation of Nickel Superalloy Inconel 718 Manufactured by Additive Manufacturing

KEY WORDS:

High-temperature Oxidation, Inconel 718, LPBF, Additive Manufacturing.

PAGES: 12
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Metalurgia Física
SPECIALTY: Corrosão
SUMMARY:

LPBF (Laser Powder Bed Fusion) is an additive manufacturing technique that enables the fabrication of components with complex geometries. Its processing parameters directly influence the resulting material's microstructure. Inconel 718 is a nickel-based superalloy known for its excellent mechanical properties and oxidation resistance at elevated temperatures. However, when produced by additive manufacturing, its anisotropic microstructural characteristics may affect oxidation resistance, potentially compromising mechanical integrity. This study investigates the effects of high-temperature exposure on Inconel 718 manufactured by LPBF. Samples were produced using two different scanning strategies and subjected to aging heat treatment or left untreated. They were built in three different orientations: X, Y, and Z, and exposed to three oxidation test regimes: isothermal oxidation at 1000 °C for 24 hours, quasi-isothermal oxidation at 850 °C for 300 hours, and cyclic oxidation at 850 °C for 300 cycles. Mass change was measured, and surface characterization was performed. Conventionally forged samples were used as a reference for comparison. Analyses using ANOVA, optical microscopy (OM), scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS), and X-ray diffraction (XRD) revealed a strong influence of processing parameters. Under isothermal conditions, samples fabricated with a 0° scanning strategy exhibited better performance compared to those produced at 67°, showing lower mass gain. Heat treatment promoted grain recrystallization, improving oxidation resistance in some cases. The X and Y surfaces showed mass gains similar to those of the 0° strategy, with better performance observed in untreated samples. The Z surface showed the lowest mass gain, with better performance for heat-treated specimens. Under quasi-isothermal conditions, most trends were consistent with those observed in the isothermal regime, including the best and worst performing configurations. Preliminary results from the cyclic oxidation tests suggest different configurations may lead to better or worse behavior in terms of mass gain.

BANKING MEMBERS:
Presidente - 1049564 - ARTUR MARIANO DE SOUSA MALAFAIA
Externo ao Programa - 1304750 - RHUAN COSTA SOUZA
Externo à Instituição - JOÃO GABRIEL DA CRUZ PASSOS