Electron Beam Welding of TZM plates
Autor(a) principal: | |
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Data de Publicação: | 2015 |
Tipo de documento: | Dissertação |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10362/31890 |
Resumo: | Recently, many efforts have been made to join molybdenum and its alloys, such as TZM, due to their interest for industrial applications. However, it has a poor weldability due to high thermal conductivity and high melting temperature, sensitivity to gas impurities and lack of solid state transformations leading to coarse grain formation. Electron beam welding (EBW) is a high energy density process, and welding TZM can result in a smaller fusion and heat affected zones. The aim of this study was to perform an exploratory investigation on the ability of EBW to weld TZM, focusing on the major process parameters, the clamping system and evaluate the effect on the weld tensile strength. The selection of the parameter values and their refinement was performed using design of experiments. Sound welds were obtained, free of pores, cracks and misalignments. A dedicated clamping system was designed, manufactured, and proved to be of major importance. Tensile strength was close to 80% of the base material, which is remarkably good for this alloy. Pre- and post-weld treatment had no significant effect on the welding strength. However, further work is needed to minimize grain coarsening, eventually by stirring the molten pool using beam deflection. |
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Electron Beam Welding of TZM platesElectron Beam WeldingMolybdenumTZM AlloyDesign of ExperimentsPreheatingPost weld heat treatmentDomínio/Área Científica::Engenharia e Tecnologia::Engenharia MecânicaRecently, many efforts have been made to join molybdenum and its alloys, such as TZM, due to their interest for industrial applications. However, it has a poor weldability due to high thermal conductivity and high melting temperature, sensitivity to gas impurities and lack of solid state transformations leading to coarse grain formation. Electron beam welding (EBW) is a high energy density process, and welding TZM can result in a smaller fusion and heat affected zones. The aim of this study was to perform an exploratory investigation on the ability of EBW to weld TZM, focusing on the major process parameters, the clamping system and evaluate the effect on the weld tensile strength. The selection of the parameter values and their refinement was performed using design of experiments. Sound welds were obtained, free of pores, cracks and misalignments. A dedicated clamping system was designed, manufactured, and proved to be of major importance. Tensile strength was close to 80% of the base material, which is remarkably good for this alloy. Pre- and post-weld treatment had no significant effect on the welding strength. However, further work is needed to minimize grain coarsening, eventually by stirring the molten pool using beam deflection.Miranda, RosaEnzinger, NorbertRUNOliveira, Diogo Brízido Caldas2018-03-06T14:51:13Z2015-0920152015-09-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://hdl.handle.net/10362/31890enginfo: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:RCAAP2024-03-11T04:17:44Zoai:run.unl.pt:10362/31890Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T03:29:46.249374Repositório 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 |
Electron Beam Welding of TZM plates |
title |
Electron Beam Welding of TZM plates |
spellingShingle |
Electron Beam Welding of TZM plates Oliveira, Diogo Brízido Caldas Electron Beam Welding Molybdenum TZM Alloy Design of Experiments Preheating Post weld heat treatment Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Mecânica |
title_short |
Electron Beam Welding of TZM plates |
title_full |
Electron Beam Welding of TZM plates |
title_fullStr |
Electron Beam Welding of TZM plates |
title_full_unstemmed |
Electron Beam Welding of TZM plates |
title_sort |
Electron Beam Welding of TZM plates |
author |
Oliveira, Diogo Brízido Caldas |
author_facet |
Oliveira, Diogo Brízido Caldas |
author_role |
author |
dc.contributor.none.fl_str_mv |
Miranda, Rosa Enzinger, Norbert RUN |
dc.contributor.author.fl_str_mv |
Oliveira, Diogo Brízido Caldas |
dc.subject.por.fl_str_mv |
Electron Beam Welding Molybdenum TZM Alloy Design of Experiments Preheating Post weld heat treatment Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Mecânica |
topic |
Electron Beam Welding Molybdenum TZM Alloy Design of Experiments Preheating Post weld heat treatment Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Mecânica |
description |
Recently, many efforts have been made to join molybdenum and its alloys, such as TZM, due to their interest for industrial applications. However, it has a poor weldability due to high thermal conductivity and high melting temperature, sensitivity to gas impurities and lack of solid state transformations leading to coarse grain formation. Electron beam welding (EBW) is a high energy density process, and welding TZM can result in a smaller fusion and heat affected zones. The aim of this study was to perform an exploratory investigation on the ability of EBW to weld TZM, focusing on the major process parameters, the clamping system and evaluate the effect on the weld tensile strength. The selection of the parameter values and their refinement was performed using design of experiments. Sound welds were obtained, free of pores, cracks and misalignments. A dedicated clamping system was designed, manufactured, and proved to be of major importance. Tensile strength was close to 80% of the base material, which is remarkably good for this alloy. Pre- and post-weld treatment had no significant effect on the welding strength. However, further work is needed to minimize grain coarsening, eventually by stirring the molten pool using beam deflection. |
publishDate |
2015 |
dc.date.none.fl_str_mv |
2015-09 2015 2015-09-01T00:00:00Z 2018-03-06T14:51:13Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10362/31890 |
url |
http://hdl.handle.net/10362/31890 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
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.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 |
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1799137922651258880 |