Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy
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/10316/95987 https://doi.org/10.1016/j.jmrt.2021.10.008 |
Resumo: | A detailed microstructural analysis during the intermediate stages of fabrication of NiTi orthodontic archwire is carried out in this study. These microstructural findings were related to the phase transformation characteristics such as start and finish transformation temperature, thermal hysteresis, etc. The objective was to monitor the transformation window during the different stages of thermomechanical processing. The casted alloy was further subjected to combinations of hot and cold forging steps with intermediate annealing. Four different sample conditions were prepared. The microstructure development in these samples was studied through electron back-scattered diffraction and synchrotron radiation X-ray diffraction (SR-XRD) techniques. The phase transformation temperatures were determined by differential scanning calorimetric measurements. The microstructures showed grain boundary serrations, very large grains of austenite, twin-like features within austenite grains and mixed-phase distribution of austenite and martensite. The differences in microstructures were also clear in terms of local in-grain misorientation and grain boundary fractions. SR-XRD measurements further revealed possible precipitation of Ni4Ti3 and Ni3Ti. The martensite start temperature (Ms) was seen to be a clear function of high angle grain boundary fraction, while the finish temperature (Mf) showed an inverse trend. The transformation interval, Ms–Mf is related to the stored energy of austenite grains that determines the driving force to overcome the frictional work opposing the movement of the habit plane, while and Af –As largely depends on the elastic energy stored of the martensite plates during its growth. The hysteresis during reverse transformation (M → A) was related to the local in-grain misorientation. © 2021 |
id |
RCAP_2e29f3efcdc161ef7e541c096ec44990 |
---|---|
oai_identifier_str |
oai:estudogeral.uc.pt:10316/95987 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloyElectron back-scattered diffractionShape memory alloysSynchrotron radiation X-ray diffractionThermomechanical processA detailed microstructural analysis during the intermediate stages of fabrication of NiTi orthodontic archwire is carried out in this study. These microstructural findings were related to the phase transformation characteristics such as start and finish transformation temperature, thermal hysteresis, etc. The objective was to monitor the transformation window during the different stages of thermomechanical processing. The casted alloy was further subjected to combinations of hot and cold forging steps with intermediate annealing. Four different sample conditions were prepared. The microstructure development in these samples was studied through electron back-scattered diffraction and synchrotron radiation X-ray diffraction (SR-XRD) techniques. The phase transformation temperatures were determined by differential scanning calorimetric measurements. The microstructures showed grain boundary serrations, very large grains of austenite, twin-like features within austenite grains and mixed-phase distribution of austenite and martensite. The differences in microstructures were also clear in terms of local in-grain misorientation and grain boundary fractions. SR-XRD measurements further revealed possible precipitation of Ni4Ti3 and Ni3Ti. The martensite start temperature (Ms) was seen to be a clear function of high angle grain boundary fraction, while the finish temperature (Mf) showed an inverse trend. The transformation interval, Ms–Mf is related to the stored energy of austenite grains that determines the driving force to overcome the frictional work opposing the movement of the habit plane, while and Af –As largely depends on the elastic energy stored of the martensite plates during its growth. The hysteresis during reverse transformation (M → A) was related to the local in-grain misorientation. © 2021Elsevier2021info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://hdl.handle.net/10316/95987http://hdl.handle.net/10316/95987https://doi.org/10.1016/j.jmrt.2021.10.008eng22387854Rodrigues, Patrícia FreitasReshie, HatimSousa, Talita Gama dePaula, Andersan dos SantosBraz Fernandes, Francisco ManuelBasu, Ritwikinfo: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:RCAAP2022-05-25T03:37:53Zoai:estudogeral.uc.pt:10316/95987Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T21:14:21.768597Repositório 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 |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy |
title |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy |
spellingShingle |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy Rodrigues, Patrícia Freitas Electron back-scattered diffraction Shape memory alloys Synchrotron radiation X-ray diffraction Thermomechanical process |
title_short |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy |
title_full |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy |
title_fullStr |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy |
title_full_unstemmed |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy |
title_sort |
Controlling the phase transformation window during stages of hot/cold forging of Ni-rich Ni–Ti alloy |
author |
Rodrigues, Patrícia Freitas |
author_facet |
Rodrigues, Patrícia Freitas Reshie, Hatim Sousa, Talita Gama de Paula, Andersan dos Santos Braz Fernandes, Francisco Manuel Basu, Ritwik |
author_role |
author |
author2 |
Reshie, Hatim Sousa, Talita Gama de Paula, Andersan dos Santos Braz Fernandes, Francisco Manuel Basu, Ritwik |
author2_role |
author author author author author |
dc.contributor.author.fl_str_mv |
Rodrigues, Patrícia Freitas Reshie, Hatim Sousa, Talita Gama de Paula, Andersan dos Santos Braz Fernandes, Francisco Manuel Basu, Ritwik |
dc.subject.por.fl_str_mv |
Electron back-scattered diffraction Shape memory alloys Synchrotron radiation X-ray diffraction Thermomechanical process |
topic |
Electron back-scattered diffraction Shape memory alloys Synchrotron radiation X-ray diffraction Thermomechanical process |
description |
A detailed microstructural analysis during the intermediate stages of fabrication of NiTi orthodontic archwire is carried out in this study. These microstructural findings were related to the phase transformation characteristics such as start and finish transformation temperature, thermal hysteresis, etc. The objective was to monitor the transformation window during the different stages of thermomechanical processing. The casted alloy was further subjected to combinations of hot and cold forging steps with intermediate annealing. Four different sample conditions were prepared. The microstructure development in these samples was studied through electron back-scattered diffraction and synchrotron radiation X-ray diffraction (SR-XRD) techniques. The phase transformation temperatures were determined by differential scanning calorimetric measurements. The microstructures showed grain boundary serrations, very large grains of austenite, twin-like features within austenite grains and mixed-phase distribution of austenite and martensite. The differences in microstructures were also clear in terms of local in-grain misorientation and grain boundary fractions. SR-XRD measurements further revealed possible precipitation of Ni4Ti3 and Ni3Ti. The martensite start temperature (Ms) was seen to be a clear function of high angle grain boundary fraction, while the finish temperature (Mf) showed an inverse trend. The transformation interval, Ms–Mf is related to the stored energy of austenite grains that determines the driving force to overcome the frictional work opposing the movement of the habit plane, while and Af –As largely depends on the elastic energy stored of the martensite plates during its growth. The hysteresis during reverse transformation (M → A) was related to the local in-grain misorientation. © 2021 |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021 |
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/10316/95987 http://hdl.handle.net/10316/95987 https://doi.org/10.1016/j.jmrt.2021.10.008 |
url |
http://hdl.handle.net/10316/95987 https://doi.org/10.1016/j.jmrt.2021.10.008 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
22387854 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
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_ |
1799134041294766080 |