Size-Dependent Structural Properties of a High-Nb TiAl Alloy Powder

TiAl-based alloys are promising light weight structural materials for high temperature applications in the field of aerospace. Recently, fabrication technologies starting from powders including powder metallurgy and additive manufacturing have been developed to overcome the difficulties in the proce...

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Autores principales: Liu, Binglin, Wang, Maosong, Du, Yulei, Li, Jingxiao
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6981939/
https://www.ncbi.nlm.nih.gov/pubmed/31906301
http://dx.doi.org/10.3390/ma13010161
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author Liu, Binglin
Wang, Maosong
Du, Yulei
Li, Jingxiao
author_facet Liu, Binglin
Wang, Maosong
Du, Yulei
Li, Jingxiao
author_sort Liu, Binglin
collection PubMed
description TiAl-based alloys are promising light weight structural materials for high temperature applications in the field of aerospace. Recently, fabrication technologies starting from powders including powder metallurgy and additive manufacturing have been developed to overcome the difficulties in the processing, machining and shaping of TiAl-based alloys. Spherical alloy powders with different particle size distributions are usually used in these fabrication techniques. The purpose of this study is to reveal the size-dependent structural properties of a high-Nb TiAl powder for these fabrication technologies starting from powders. A high-Nb TiAl pre-alloyed powder with nominal composition of Ti-48Al-2Cr-8Nb (at. %) was prepared by the electrode induction melting gas atomization (EIGA) method. The phase structure and morphology of the as-atomized powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The size-dependent structural changes of the as-atomized powders with different sizes were studied by differential scanning calorimetry (DSC) and in situ high temperature XRD. It was found that with decreasing the powder size, the content of the γ-TiAl phase decreases and the α(2)-Ti(3)Al phase increases. The α(2)-Ti(3)Al to γ-TiAl phase transformation was found in the temperature range of 600–770 °C. Based on the present work, the structural characteristics of TiAl powders are strongly dependent on their particle size, which should be considered in optimizing the process parameters of TiAl alloys fabricated from powders.
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spelling pubmed-69819392020-02-07 Size-Dependent Structural Properties of a High-Nb TiAl Alloy Powder Liu, Binglin Wang, Maosong Du, Yulei Li, Jingxiao Materials (Basel) Article TiAl-based alloys are promising light weight structural materials for high temperature applications in the field of aerospace. Recently, fabrication technologies starting from powders including powder metallurgy and additive manufacturing have been developed to overcome the difficulties in the processing, machining and shaping of TiAl-based alloys. Spherical alloy powders with different particle size distributions are usually used in these fabrication techniques. The purpose of this study is to reveal the size-dependent structural properties of a high-Nb TiAl powder for these fabrication technologies starting from powders. A high-Nb TiAl pre-alloyed powder with nominal composition of Ti-48Al-2Cr-8Nb (at. %) was prepared by the electrode induction melting gas atomization (EIGA) method. The phase structure and morphology of the as-atomized powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The size-dependent structural changes of the as-atomized powders with different sizes were studied by differential scanning calorimetry (DSC) and in situ high temperature XRD. It was found that with decreasing the powder size, the content of the γ-TiAl phase decreases and the α(2)-Ti(3)Al phase increases. The α(2)-Ti(3)Al to γ-TiAl phase transformation was found in the temperature range of 600–770 °C. Based on the present work, the structural characteristics of TiAl powders are strongly dependent on their particle size, which should be considered in optimizing the process parameters of TiAl alloys fabricated from powders. MDPI 2020-01-01 /pmc/articles/PMC6981939/ /pubmed/31906301 http://dx.doi.org/10.3390/ma13010161 Text en © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Liu, Binglin
Wang, Maosong
Du, Yulei
Li, Jingxiao
Size-Dependent Structural Properties of a High-Nb TiAl Alloy Powder
title Size-Dependent Structural Properties of a High-Nb TiAl Alloy Powder
title_full Size-Dependent Structural Properties of a High-Nb TiAl Alloy Powder
title_fullStr Size-Dependent Structural Properties of a High-Nb TiAl Alloy Powder
title_full_unstemmed Size-Dependent Structural Properties of a High-Nb TiAl Alloy Powder
title_short Size-Dependent Structural Properties of a High-Nb TiAl Alloy Powder
title_sort size-dependent structural properties of a high-nb tial alloy powder
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6981939/
https://www.ncbi.nlm.nih.gov/pubmed/31906301
http://dx.doi.org/10.3390/ma13010161
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AT lijingxiao sizedependentstructuralpropertiesofahighnbtialalloypowder