The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
D. M. Rodrigues - One of the best experts on this subject based on the ideXlab platform.
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analysis of high temperature plastic behaviour and its relation with Weldability in friction stir welding for aluminium alloys aa5083 h111 and aa6082 t6
Materials & Design, 2012Co-Authors: Cátia Sofia Jorge Leitão, R. Louro, D. M. RodriguesAbstract:The influence of the plastic behaviour of two aluminium alloys, very popular in welding construction, on friction stir Weldability, is analysed in this work. The two base materials, a non-heat-treatable (AA5083H111) and a heat-treatable aluminium (AA6082-T6) alloy, are characterised by markedly different strengthening mechanisms and microstructural evolution at increasing temperatures. Their plastic behaviour, under different testing conditions, was analysed and compared. The two base materials were also welded under varied friction stir welding (FSW) conditions in order to characterise their Weldability. The relation between Weldability, material flow during FSW and the plastic behaviour of the base materials, at different temperatures, was analysed. It was found that the AA6082 alloy, which displays intense flow softening during tensile loading at high temperatures, and is sensitive to dynamic precipitation and overageing under intense non-uniform deformation, displays good Weldability in FSW. Under the same welding conditions, the AA5083 alloy, which in quasi-static conditions displays steady flow behaviour at increasing temperatures, and is sensitive to moderate hardening at high strain rates, displays poor Weldability.
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Analysis of high temperature plastic behaviour and its relation with Weldability in friction stir welding for aluminium alloys AA5083-H111 and AA6082-T6
Materials and Design, 2012Co-Authors: Cátia Sofia Jorge Leitão, R. Louro, D. M. RodriguesAbstract:The influence of the plastic behaviour of two aluminium alloys, very popular in welding construction, on friction stir Weldability, is analysed in this work. The two base materials, a non-heat-treatable (AA5083-H111) and a heat-treatable aluminium (AA6082-T6) alloy, are characterised by markedly different strengthening mechanisms and microstructural evolution at increasing temperatures. Their plastic behaviour, under different testing conditions, was analysed and compared. The two base materials were also welded under varied friction stir welding (FSW) conditions in order to characterise their Weldability. The relation between Weldability, material flow during FSW and the plastic behaviour of the base materials, at different temperatures, was analysed. It was found that the AA6082 alloy, which displays intense flow softening during tensile loading at high temperatures, and is sensitive to dynamic precipitation and overageing under intense non-uniform deformation, displays good Weldability in FSW. Under the same welding conditions, the AA5083 alloy, which in quasi-static conditions displays steady flow behaviour at increasing temperatures, and is sensitive to moderate hardening at high strain rates, displays poor Weldability. © 2012 Elsevier Ltd.
S A David - One of the best experts on this subject based on the ideXlab platform.
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welding of unique and advanced alloys for space and high temperature applications welding and Weldability of iridium and platinum alloys
Science and Technology of Welding and Joining, 2017Co-Authors: S A David, Roger G Miller, Zhili FengAbstract:In the last five decades, significant advances have been made in developing alloys for space power systems for spacecraft that travel long distances to various planets. The spacecraft are powered by radioisotope thermoelectric generators (RTGs). The fuel element in RTGs is plutonia. For safety and containment of the radioactive fuel element, the heat source is encapsulated in iridium or platinum alloys. Ir and Pt alloys are the alloys of choice for encapsulating radioisotope fuel pellets. Ir and Pt alloys were chosen because of their high-temperature properties and compatibility with the oxide fuel element and the graphite impact shells. This review addresses the alloy design and welding and Weldability of Ir and Pt alloys for use in RTGs.
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Weldability of a high entropy crmnfeconi alloy
Scripta Materialia, 2016Co-Authors: Zhenggang Wu, S A David, Zhili FengAbstract:Abstract High-entropy alloys are unique alloys in which five or more elements are presented all in high concentrations. To determine its potential as a structural alloy, a model face-centered-cubic CrMnFeCoNi alloy was selected to investigate its Weldability. Welds produced by electron beam welding show no cracking. The grain structures within the fusion zone (FZ) are controlled by the solidification behavior of the weld pool. The weldment possesses mechanical properties comparable to those of the base metal (BM) at both room and cryogenic temperatures. Compared with the BM, deformation twinning was more pronounced in the FZ of the tested alloy.
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Weldability and weld performance of candidate nickel based superalloys for advanced ultrasupercritical fossil power plants part ii Weldability and cross weld creep performance
Science and Technology of Welding and Joining, 2016Co-Authors: J A Siefert, John P. Shingledecker, J N Dupont, S A DavidAbstract:Fossil fuel will continue to be the major source of energy for the foreseeable future. To meet the demand for clean and affordable energy, an increase in the operating efficiency of fossil fired power plants is necessary. There are several initiatives worldwide to achieve efficiencies >45%HHV (higher heating value) through an increase in steam temperature (700–760°C) and pressure (27.6–34.5 MPa). Realising this goal requires materials with excellent creep rupture properties and corrosion resistance at elevated temperatures. Two previous papers addressed the welding and Weldability of ferritic and austenitic stainless steels. Welding and Weldability of nickel based alloys will be discussed in a two-part paper. In this paper, the primary focus will be on the behaviour of candidate nickel based alloys that are being proposed in advanced ultrasupercritical power plants and with regard to Weldability (Part I) and cross-weld creep performance (Part II).
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Weldability and weld performance of candidate austenitic alloys for advanced ultrasupercritical fossil power plants
Science and Technology of Welding and Joining, 2014Co-Authors: J A Siefert, S A DavidAbstract:AbstractAdvanced ultrasupercritical steam conditions of up to 760°C and 34·5 MPa have been investigated in various programmes around the world over the last two decades. To date, much progress has been made, and three candidate materials, namely ferritic, austenitic and nickel base superalloys, have been investigated for high temperature strength, corrosion resistance and Weldability. In an earlier published paper, welding and Weldability of ferritic alloys were discussed. This paper considers the unique Weldability characteristics for utilisation of austenitic stainless steels in future advanced ultrasupercritical fossil power plant designs and covers topics such as fundamentals of austenitic stainless steel welds, including Weldability, filler metals and dissimilar metal welds, and discusses the prognosis for this class of materials for advanced ultrasupercritical fossil fired power plants.
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welding and Weldability of candidate ferritic alloys for future advanced ultrasupercritical fossil power plants
Science and Technology of Welding and Joining, 2013Co-Authors: S A David, J A Siefert, Zhili FengAbstract:AbstractFossil fuels continue to be the primary source of energy in the world. The worldwide demand for clean and affordable energy will continue to grow, and a strong emphasis has been placed on increasing the efficiency and reducing the carbon footprint of new and existing fossil fired power plants. Throughout Asia, Europe and the USA, this demand is being met with programmes to develop advanced materials that have enhanced high temperature creep and corrosion properties. A new class of ferritic alloys, known as creep strength enhanced ferritic steels, has been developed to meet these requirements. This article focuses on the Weldability of the advanced ferritic alloys used in boilers and boiler components of ultrasupercritical coal fired power plants. This review focuses on alloy selection; welding and Weldability issues, including in service weld failure such as type IV cracking; welding of dissimilar metals; and weld repair. Future articles will address the welding and Weldability issues of two other...
Cátia Sofia Jorge Leitão - One of the best experts on this subject based on the ideXlab platform.
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analysis of high temperature plastic behaviour and its relation with Weldability in friction stir welding for aluminium alloys aa5083 h111 and aa6082 t6
Materials & Design, 2012Co-Authors: Cátia Sofia Jorge Leitão, R. Louro, D. M. RodriguesAbstract:The influence of the plastic behaviour of two aluminium alloys, very popular in welding construction, on friction stir Weldability, is analysed in this work. The two base materials, a non-heat-treatable (AA5083H111) and a heat-treatable aluminium (AA6082-T6) alloy, are characterised by markedly different strengthening mechanisms and microstructural evolution at increasing temperatures. Their plastic behaviour, under different testing conditions, was analysed and compared. The two base materials were also welded under varied friction stir welding (FSW) conditions in order to characterise their Weldability. The relation between Weldability, material flow during FSW and the plastic behaviour of the base materials, at different temperatures, was analysed. It was found that the AA6082 alloy, which displays intense flow softening during tensile loading at high temperatures, and is sensitive to dynamic precipitation and overageing under intense non-uniform deformation, displays good Weldability in FSW. Under the same welding conditions, the AA5083 alloy, which in quasi-static conditions displays steady flow behaviour at increasing temperatures, and is sensitive to moderate hardening at high strain rates, displays poor Weldability.
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Analysis of high temperature plastic behaviour and its relation with Weldability in friction stir welding for aluminium alloys AA5083-H111 and AA6082-T6
Materials and Design, 2012Co-Authors: Cátia Sofia Jorge Leitão, R. Louro, D. M. RodriguesAbstract:The influence of the plastic behaviour of two aluminium alloys, very popular in welding construction, on friction stir Weldability, is analysed in this work. The two base materials, a non-heat-treatable (AA5083-H111) and a heat-treatable aluminium (AA6082-T6) alloy, are characterised by markedly different strengthening mechanisms and microstructural evolution at increasing temperatures. Their plastic behaviour, under different testing conditions, was analysed and compared. The two base materials were also welded under varied friction stir welding (FSW) conditions in order to characterise their Weldability. The relation between Weldability, material flow during FSW and the plastic behaviour of the base materials, at different temperatures, was analysed. It was found that the AA6082 alloy, which displays intense flow softening during tensile loading at high temperatures, and is sensitive to dynamic precipitation and overageing under intense non-uniform deformation, displays good Weldability in FSW. Under the same welding conditions, the AA5083 alloy, which in quasi-static conditions displays steady flow behaviour at increasing temperatures, and is sensitive to moderate hardening at high strain rates, displays poor Weldability. © 2012 Elsevier Ltd.
Zhili Feng - One of the best experts on this subject based on the ideXlab platform.
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welding of unique and advanced alloys for space and high temperature applications welding and Weldability of iridium and platinum alloys
Science and Technology of Welding and Joining, 2017Co-Authors: S A David, Roger G Miller, Zhili FengAbstract:In the last five decades, significant advances have been made in developing alloys for space power systems for spacecraft that travel long distances to various planets. The spacecraft are powered by radioisotope thermoelectric generators (RTGs). The fuel element in RTGs is plutonia. For safety and containment of the radioactive fuel element, the heat source is encapsulated in iridium or platinum alloys. Ir and Pt alloys are the alloys of choice for encapsulating radioisotope fuel pellets. Ir and Pt alloys were chosen because of their high-temperature properties and compatibility with the oxide fuel element and the graphite impact shells. This review addresses the alloy design and welding and Weldability of Ir and Pt alloys for use in RTGs.
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Weldability of a high entropy crmnfeconi alloy
Scripta Materialia, 2016Co-Authors: Zhenggang Wu, S A David, Zhili FengAbstract:Abstract High-entropy alloys are unique alloys in which five or more elements are presented all in high concentrations. To determine its potential as a structural alloy, a model face-centered-cubic CrMnFeCoNi alloy was selected to investigate its Weldability. Welds produced by electron beam welding show no cracking. The grain structures within the fusion zone (FZ) are controlled by the solidification behavior of the weld pool. The weldment possesses mechanical properties comparable to those of the base metal (BM) at both room and cryogenic temperatures. Compared with the BM, deformation twinning was more pronounced in the FZ of the tested alloy.
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welding and Weldability of candidate ferritic alloys for future advanced ultrasupercritical fossil power plants
Science and Technology of Welding and Joining, 2013Co-Authors: S A David, J A Siefert, Zhili FengAbstract:AbstractFossil fuels continue to be the primary source of energy in the world. The worldwide demand for clean and affordable energy will continue to grow, and a strong emphasis has been placed on increasing the efficiency and reducing the carbon footprint of new and existing fossil fired power plants. Throughout Asia, Europe and the USA, this demand is being met with programmes to develop advanced materials that have enhanced high temperature creep and corrosion properties. A new class of ferritic alloys, known as creep strength enhanced ferritic steels, has been developed to meet these requirements. This article focuses on the Weldability of the advanced ferritic alloys used in boilers and boiler components of ultrasupercritical coal fired power plants. This review focuses on alloy selection; welding and Weldability issues, including in service weld failure such as type IV cracking; welding of dissimilar metals; and weld repair. Future articles will address the welding and Weldability issues of two other...
R. Louro - One of the best experts on this subject based on the ideXlab platform.
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analysis of high temperature plastic behaviour and its relation with Weldability in friction stir welding for aluminium alloys aa5083 h111 and aa6082 t6
Materials & Design, 2012Co-Authors: Cátia Sofia Jorge Leitão, R. Louro, D. M. RodriguesAbstract:The influence of the plastic behaviour of two aluminium alloys, very popular in welding construction, on friction stir Weldability, is analysed in this work. The two base materials, a non-heat-treatable (AA5083H111) and a heat-treatable aluminium (AA6082-T6) alloy, are characterised by markedly different strengthening mechanisms and microstructural evolution at increasing temperatures. Their plastic behaviour, under different testing conditions, was analysed and compared. The two base materials were also welded under varied friction stir welding (FSW) conditions in order to characterise their Weldability. The relation between Weldability, material flow during FSW and the plastic behaviour of the base materials, at different temperatures, was analysed. It was found that the AA6082 alloy, which displays intense flow softening during tensile loading at high temperatures, and is sensitive to dynamic precipitation and overageing under intense non-uniform deformation, displays good Weldability in FSW. Under the same welding conditions, the AA5083 alloy, which in quasi-static conditions displays steady flow behaviour at increasing temperatures, and is sensitive to moderate hardening at high strain rates, displays poor Weldability.
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Analysis of high temperature plastic behaviour and its relation with Weldability in friction stir welding for aluminium alloys AA5083-H111 and AA6082-T6
Materials and Design, 2012Co-Authors: Cátia Sofia Jorge Leitão, R. Louro, D. M. RodriguesAbstract:The influence of the plastic behaviour of two aluminium alloys, very popular in welding construction, on friction stir Weldability, is analysed in this work. The two base materials, a non-heat-treatable (AA5083-H111) and a heat-treatable aluminium (AA6082-T6) alloy, are characterised by markedly different strengthening mechanisms and microstructural evolution at increasing temperatures. Their plastic behaviour, under different testing conditions, was analysed and compared. The two base materials were also welded under varied friction stir welding (FSW) conditions in order to characterise their Weldability. The relation between Weldability, material flow during FSW and the plastic behaviour of the base materials, at different temperatures, was analysed. It was found that the AA6082 alloy, which displays intense flow softening during tensile loading at high temperatures, and is sensitive to dynamic precipitation and overageing under intense non-uniform deformation, displays good Weldability in FSW. Under the same welding conditions, the AA5083 alloy, which in quasi-static conditions displays steady flow behaviour at increasing temperatures, and is sensitive to moderate hardening at high strain rates, displays poor Weldability. © 2012 Elsevier Ltd.
