Effect of Mo substitution for Nb on the beta-21S alloy: processing, microstructural stability, mechanical properties and oxidation resistance

• Grant number: 19/09819-9
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2019
• End date: April 30, 2022
• 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

Abstract

The b-21S titanium alloy corresponds to one of the main titanium alloys for structural applications at high temperatures. Its nominal composition is Ti-15Mo-2,7Nb-3Al-0,2Si (% by weight) or near Ti-8Mo-1.5Nb-5,7Al-0.6Si (% atomic). There is no systematic data on the literature on the possible microstructures developed in this alloys; its mechanical properties and oxidation resistance. Particularly, the reasons that led to the addition of Nb, especially the amount of 1.5% at. Nb in the composition of the alloy. Thus, it is the objective of this project to carry out a work to evaluate the effect of the substitution of Mo by Nb in the processing; microstructural characteristics and properties (mechanical / oxidation) of the alloys produced. The alloys will be processed by arc melting; rotary swage; heat-treatments and characterized by optical microscopy; scanning electron microscopy; X-ray diffraction. Depending on the observed microstructural characteristics, characterizations via Electron Back-Scattering Diffraction and transmission electron microscopy may also be performed. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FERREIRA, L. M.; CHAIA, N.; COELHO, G. C.; NUNES, C. A.. Oxidation behavior of STA beta-21S alloy and variants [Ti-xNb-yMo-5.6Al-0.5Si at%; x + y=9.5]. Corrosion Science, v. 203, p. 10-pg., 2022-07-15. (19/09819-9)