Microstructural and Mechanical Characterization of Directionally Solidified Conventional and Nb-Modified Mar-M247 Superalloy
dc.contributor.author | Costa, A. M.S. | |
dc.contributor.author | Lopes, E. S.N. | |
dc.contributor.author | Contieri, R. J. | |
dc.contributor.author | Caram, R. | |
dc.contributor.author | Baldan, R. [UNESP] | |
dc.contributor.author | Fuchs, G. E. | |
dc.contributor.author | Nunes, C. A. | |
dc.contributor.institution | Methodist University of Piracicaba | |
dc.contributor.institution | Universidade Estadual de Campinas (UNICAMP) | |
dc.contributor.institution | Universidade Estadual Paulista (Unesp) | |
dc.contributor.institution | University of Florida | |
dc.contributor.institution | Universidade de São Paulo (USP) | |
dc.date.accessioned | 2019-10-06T16:26:09Z | |
dc.date.available | 2019-10-06T16:26:09Z | |
dc.date.issued | 2019-04-01 | |
dc.description.abstract | This study analyzes the effects of replacing Ta by Nb (at.% basis) in the phase transformation temperatures, Scheil solidification behavior, and microstructural mechanical features of a Nb-modified as well as conventional Mar-M247 superalloys. Both alloys were directionally solidified at a withdrawal rate of 18 cm/h under a thermal gradient of about 80 °C/cm. DSC results were compared to thermodynamic simulations of phase transformation temperatures and showed a good correlation. The replacement of Ta by Nb has not altered the solidification path of Mar-M247, keeping the sequence L → L + γ → L + γ + MC → L + γ + MC + γ/γ′ eutectic. Due to the segregation of Hf and Zr to the very last liquid to solidify, a low melting point γ/Ni 5 (Hf,Zr) constituent was observed. The as-solidified microstructures of both Mar-M247(Nb) and Mar-M247 were constituted of columnar dendrites of gamma matrix (γ) phase with cuboidal gamma-prime (γ′) precipitates. In addition, γ/γ′-eutectic was observed in the interdendritic region along with MC carbides in blocky, script (blocky dendritic), needle-like and fine nodular morphologies. Both alloys contained about 1.5 vol.% of MC carbides. The MC carbides in Mar-M247(Nb) and Mar-M247 are, respectively, Nb-rich and Ta-rich, with only a limited amount of Hf being detected in the MC phase. The yield stress of Nb-modified Mar-M247 showed higher values up to 750 °C. For higher temperatures, above 800 °C, a conventional Mar-M247 presented a higher value of yield stress. | en |
dc.description.affiliation | Methodist University of Piracicaba, R. Luis Ometto, Km 24 | |
dc.description.affiliation | School of Mechanical Engineering University of Campinas | |
dc.description.affiliation | School of Applied Sciences University of Campinas | |
dc.description.affiliation | São Paulo State University (Unesp), Campus of Itapeva | |
dc.description.affiliation | Materials Science and Engineering Department University of Florida | |
dc.description.affiliation | Escola de Engenharia de Lorena Universidade de Sao Paulo, Pólo Urbo-Industrial Gleba AI-6 | |
dc.description.affiliationUnesp | São Paulo State University (Unesp), Campus of Itapeva | |
dc.format.extent | 2427-2438 | |
dc.identifier | http://dx.doi.org/10.1007/s11665-019-04014-1 | |
dc.identifier.citation | Journal of Materials Engineering and Performance, v. 28, n. 4, p. 2427-2438, 2019. | |
dc.identifier.doi | 10.1007/s11665-019-04014-1 | |
dc.identifier.issn | 1544-1024 | |
dc.identifier.issn | 1059-9495 | |
dc.identifier.lattes | 1514019536224632 | |
dc.identifier.orcid | 0000-0003-4172-3689 | |
dc.identifier.scopus | 2-s2.0-85064432015 | |
dc.identifier.uri | http://hdl.handle.net/11449/188989 | |
dc.language.iso | eng | |
dc.relation.ispartof | Journal of Materials Engineering and Performance | |
dc.rights.accessRights | Acesso aberto | |
dc.source | Scopus | |
dc.subject | Mar-M247 superalloy | |
dc.subject | Nb-modified Mar-M247 | |
dc.subject | thermodynamic simulation | |
dc.title | Microstructural and Mechanical Characterization of Directionally Solidified Conventional and Nb-Modified Mar-M247 Superalloy | en |
dc.type | Artigo | |
unesp.author.lattes | 1514019536224632[5] | |
unesp.author.orcid | 0000-0003-4172-3689[5] | |
unesp.campus | Universidade Estadual Paulista (Unesp), Instituto de Ciências e Engenharia, Itapeva | pt |
unesp.department | Engenharia Industrial Madeireira - ICE | pt |