Evaluation of the influence of Mo/Nb/Ta/Ta addition on the oxidation of nickel-based Superalloys for Turbine Disks Applications through the investigation of model 80Ni-18Cr-2M (at. - M=Mo, Nb, Ta, Ti) alloys.

• Grant number: 24/02749-3
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2024
• End date: July 31, 2026
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Carlos Angelo Nunes
• Grantee: Carlos Angelo Nunes
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil
• Associated researchers: Gilberto Carvalho Coelho ; Nabil Chaia
• Associated scholarship(s): 24/21315-4 - Evaluation of the effect of Ti replacement by Nb on the oxidation behavior at 700 C and 800 C of Nickel -based alloy AT80A (ALLOY 80A/UNS N07080)., BP.IC

Abstract

Turbine discs are critical components of jet engines in the aerospace industry. The severe environmental conditions found in the hot parts of the jet engine imply that components should have good oxidation/corrosion resistance, especially considering the important damage that these processes can cause, including their effects on the mechanical behavior of the material at high temperatures. We have recently evaluated the effect of total Ti replacement by Nb on oxidation behavior of a multi-component nickel-base superalloy, finding very interesting results. From this, the following question arose? Is it possible to infer the effect of the addition of alloying elements on the oxidation of Ni-base superalloy for disc, from a simple model Ni-Cr alloy? To this end, we conducted preliminary experiments, investigating the effect of Ti and Nb addition to a Ni-Cr binary alloy [model alloy] on oxidation behavior at 800 oC. The preliminary results were promising. From this, it is intended to conduct a systematic investigation involving the addition of Mo, Nb, Ta and Ti to a Ni-18Cr (at.%) model alloy and evaluate their behavior when these materials are exposed to 800 oC in air for periods of time up to 1000 h. In the proposal we present the questions we intend to answer and for this an important set of experimental techniques should be used: arc melting; heat treatment; scanning electron microscopy; Laser Confocal Microscopy; Spectroscopy of Photoelectron (XPS); Atomic probe tomography (APT). (AU)