Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation
Autor(a) principal: | |
---|---|
Data de Publicação: | 2021 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10400.9/3638 |
Resumo: | ABSTRACT: Liquid film migration is of great practical importance in materials engineering. The phenomenon has been shown to depend on thermal gradients and coherency strain, but no single driving mechanism seems capable of justifying the whole array of experimental observations. On the other hand, the inevitable capillarity effects are often disregarded due to the unknown 3-dimensional geometry of the system. Here, we present evidence of liquid film migration governed primarily by capillarity through a microstructural setup of cylindrical interfaces that allows clear interpretation and modeling. The experiments rely on the strong oxygen-gettering ability of tantalum fibers dispersed in a tungsten matrix and on field-enhanced diffusivity provided by pulse plasma compaction. Tantalum scavenges the residual oxygen present in the W powder and, as a result, oxide films grow around the fibers. These oxide tubes, in liquid state during sintering, migrate toward the fiber axis and eventually become oxide rods surrounded by metallic Ta. The process is driven by the Gibbs-Thomson effect that generates the required composition gradient across the liquid film. An analytical description of the film evolution is implemented by combining the incoming O flux with capillarity-driven migration. Possible contributions from other mechanisms are examined and the relevance of the Gibbs-Thomson effect to the general phenomenon of liquid film migration is established. |
id |
RCAP_08464180a271b59a98c96678ca8d12f2 |
---|---|
oai_identifier_str |
oai:repositorio.lneg.pt:10400.9/3638 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidationMaterialsLiquid film migrationOxide filmKineticsMechanical propertiesABSTRACT: Liquid film migration is of great practical importance in materials engineering. The phenomenon has been shown to depend on thermal gradients and coherency strain, but no single driving mechanism seems capable of justifying the whole array of experimental observations. On the other hand, the inevitable capillarity effects are often disregarded due to the unknown 3-dimensional geometry of the system. Here, we present evidence of liquid film migration governed primarily by capillarity through a microstructural setup of cylindrical interfaces that allows clear interpretation and modeling. The experiments rely on the strong oxygen-gettering ability of tantalum fibers dispersed in a tungsten matrix and on field-enhanced diffusivity provided by pulse plasma compaction. Tantalum scavenges the residual oxygen present in the W powder and, as a result, oxide films grow around the fibers. These oxide tubes, in liquid state during sintering, migrate toward the fiber axis and eventually become oxide rods surrounded by metallic Ta. The process is driven by the Gibbs-Thomson effect that generates the required composition gradient across the liquid film. An analytical description of the film evolution is implemented by combining the incoming O flux with capillarity-driven migration. Possible contributions from other mechanisms are examined and the relevance of the Gibbs-Thomson effect to the general phenomenon of liquid film migration is established.ElsevierRepositório do LNEGDias, MartaRosinski, M.Rodrigues, P. C. R.Correia, J.B.Carvalho, Patricia Almeida2021-12-17T17:34:19Z2021-10-01T00:00:00Z2021-10-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10400.9/3638engDias, M... [et.al.] - Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation. In: Acta Materialia, 2021, Vol. 218, article nº 1172161359-645410.1016/j.actamat.2021.1172161873-2453info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2022-09-06T12:29:20Zoai:repositorio.lneg.pt:10400.9/3638Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T15:36:50.796794Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation |
title |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation |
spellingShingle |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation Dias, Marta Materials Liquid film migration Oxide film Kinetics Mechanical properties |
title_short |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation |
title_full |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation |
title_fullStr |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation |
title_full_unstemmed |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation |
title_sort |
Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation |
author |
Dias, Marta |
author_facet |
Dias, Marta Rosinski, M. Rodrigues, P. C. R. Correia, J.B. Carvalho, Patricia Almeida |
author_role |
author |
author2 |
Rosinski, M. Rodrigues, P. C. R. Correia, J.B. Carvalho, Patricia Almeida |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Repositório do LNEG |
dc.contributor.author.fl_str_mv |
Dias, Marta Rosinski, M. Rodrigues, P. C. R. Correia, J.B. Carvalho, Patricia Almeida |
dc.subject.por.fl_str_mv |
Materials Liquid film migration Oxide film Kinetics Mechanical properties |
topic |
Materials Liquid film migration Oxide film Kinetics Mechanical properties |
description |
ABSTRACT: Liquid film migration is of great practical importance in materials engineering. The phenomenon has been shown to depend on thermal gradients and coherency strain, but no single driving mechanism seems capable of justifying the whole array of experimental observations. On the other hand, the inevitable capillarity effects are often disregarded due to the unknown 3-dimensional geometry of the system. Here, we present evidence of liquid film migration governed primarily by capillarity through a microstructural setup of cylindrical interfaces that allows clear interpretation and modeling. The experiments rely on the strong oxygen-gettering ability of tantalum fibers dispersed in a tungsten matrix and on field-enhanced diffusivity provided by pulse plasma compaction. Tantalum scavenges the residual oxygen present in the W powder and, as a result, oxide films grow around the fibers. These oxide tubes, in liquid state during sintering, migrate toward the fiber axis and eventually become oxide rods surrounded by metallic Ta. The process is driven by the Gibbs-Thomson effect that generates the required composition gradient across the liquid film. An analytical description of the film evolution is implemented by combining the incoming O flux with capillarity-driven migration. Possible contributions from other mechanisms are examined and the relevance of the Gibbs-Thomson effect to the general phenomenon of liquid film migration is established. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-12-17T17:34:19Z 2021-10-01T00:00:00Z 2021-10-01T00:00:00Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10400.9/3638 |
url |
http://hdl.handle.net/10400.9/3638 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Dias, M... [et.al.] - Gibbs-Thomson effect as driving force for liquid film migration: Converting metallic into ceramic fibers through intrinsic oxidation. In: Acta Materialia, 2021, Vol. 218, article nº 117216 1359-6454 10.1016/j.actamat.2021.117216 1873-2453 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier |
publisher.none.fl_str_mv |
Elsevier |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
_version_ |
1799130234957594624 |