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Atom probe tomography analysis of the distribution of rhenium in nickel alloys / A. Mottura in Acta materialia, Vol. 58 N° 3 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 931-942 Titre : Atom probe tomography analysis of the distribution of rhenium in nickel alloys Type de document : texte imprimé Auteurs : A. Mottura, Auteur ; N. Warnken, Auteur ; M. K. Miller, Auteur Article en page(s) : pp. 931-942 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Nickel  alloys  Atom  probe  tomography  Rhenium-effect Index. décimale : 669 Métallurgie Résumé : Atom probe tomography (APT) is used to characterise the distributions of rhenium in a binary Ni–Re alloy and the nickel-based single-crystal CMSX-4 superalloy. A purpose-built algorithm is developed to quantify the size distribution of solute clusters, and applied to the APT datasets to critique the hypothesis that rhenium is prone to the formation of clusters in these systems. No evidence is found to indicate that rhenium forms solute clusters above the level expected from random fluctuations. In CMSX-4, enrichment of Re is detected in the matrix phase close to the matrix/precipitate (γ/γ′) phase boundaries. Phase field modelling indicates that this is due to the migration of the γ/γ′ interface during cooling from the temperature of operation. Thus, neither clustering of rhenium nor interface enrichments can be the cause of the enhancement in high temperature mechanical properties conferred by rhenium alloying. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%23 [...] [article] Atom probe tomography analysis of the distribution of rhenium in nickel alloys [texte imprimé] / A. Mottura, Auteur ; N. Warnken, Auteur ; M. K. Miller, Auteur . - pp. 931-942. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 931-942 Mots-clés : Nickel  alloys  Atom  probe  tomography  Rhenium-effect Index. décimale : 669 Métallurgie Résumé : Atom probe tomography (APT) is used to characterise the distributions of rhenium in a binary Ni–Re alloy and the nickel-based single-crystal CMSX-4 superalloy. A purpose-built algorithm is developed to quantify the size distribution of solute clusters, and applied to the APT datasets to critique the hypothesis that rhenium is prone to the formation of clusters in these systems. No evidence is found to indicate that rhenium forms solute clusters above the level expected from random fluctuations. In CMSX-4, enrichment of Re is detected in the matrix phase close to the matrix/precipitate (γ/γ′) phase boundaries. Phase field modelling indicates that this is due to the migration of the γ/γ′ interface during cooling from the temperature of operation. Thus, neither clustering of rhenium nor interface enrichments can be the cause of the enhancement in high temperature mechanical properties conferred by rhenium alloying. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%23 [...]

Atom probe tomography analysis of the distribution of rhenium in nickel alloys / A. Mottura in Acta materialia, Vol. 58 N° 3 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 931–942 Titre : Atom probe tomography analysis of the distribution of rhenium in nickel alloys Type de document : texte imprimé Auteurs : A. Mottura, Auteur ; N. Warnken, Auteur ; M. K. Miller, Auteur Année de publication : 2011 Article en page(s) : pp. 931–942 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Nickel  alloys  Atom  probe  tomography  Rhenium-effect Résumé : Atom probe tomography (APT) is used to characterise the distributions of rhenium in a binary Ni–Re alloy and the nickel-based single-crystal CMSX-4 superalloy. A purpose-built algorithm is developed to quantify the size distribution of solute clusters, and applied to the APT datasets to critique the hypothesis that rhenium is prone to the formation of clusters in these systems. No evidence is found to indicate that rhenium forms solute clusters above the level expected from random fluctuations. In CMSX-4, enrichment of Re is detected in the matrix phase close to the matrix/precipitate (γ/γ′) phase boundaries. Phase field modelling indicates that this is due to the migration of the γ/γ′ interface during cooling from the temperature of operation. Thus, neither clustering of rhenium nor interface enrichments can be the cause of the enhancement in high temperature mechanical properties conferred by rhenium alloying. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409006879 [article] Atom probe tomography analysis of the distribution of rhenium in nickel alloys [texte imprimé] / A. Mottura, Auteur ; N. Warnken, Auteur ; M. K. Miller, Auteur . - 2011 . - pp. 931–942. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 931–942 Mots-clés : Nickel  alloys  Atom  probe  tomography  Rhenium-effect Résumé : Atom probe tomography (APT) is used to characterise the distributions of rhenium in a binary Ni–Re alloy and the nickel-based single-crystal CMSX-4 superalloy. A purpose-built algorithm is developed to quantify the size distribution of solute clusters, and applied to the APT datasets to critique the hypothesis that rhenium is prone to the formation of clusters in these systems. No evidence is found to indicate that rhenium forms solute clusters above the level expected from random fluctuations. In CMSX-4, enrichment of Re is detected in the matrix phase close to the matrix/precipitate (γ/γ′) phase boundaries. Phase field modelling indicates that this is due to the migration of the γ/γ′ interface during cooling from the temperature of operation. Thus, neither clustering of rhenium nor interface enrichments can be the cause of the enhancement in high temperature mechanical properties conferred by rhenium alloying. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409006879

Carbon supersaturation of ferrite in a nanocrystalline bainitic steel / F. G. Caballero in Acta materialia, Vol. 58 N° 7 (Avril 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 7 (Avril 2010) . - pp. 2338–2343 Titre : Carbon supersaturation of ferrite in a nanocrystalline bainitic steel Type de document : texte imprimé Auteurs : F. G. Caballero, Auteur ; M. K. Miller, Auteur ; C. Garcia-Mateo, Auteur Année de publication : 2011 Article en page(s) : pp. 2338–2343 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Steels  Bainite  Three-dimensional  atom  probe  (3DAP) Résumé : The extremely slow transformation kinetics of a nanocrystalline bainitic steel allows the carbon content of the bainitic ferrite away from any carbon-enriched regions such as dislocations and boundaries to be determined by atom probe tomography as the bainite transformation progresses at 200 °C. A high level of carbon, well above that expected from para-equilibrium with austenite, has been detected in solid solution in bainitic ferrite at the early stage of transformation. Results provide strong evidence that bainite transformation is essentially displacive in nature so that the newly formed bainitic ferrite retains much of the carbon content of the parent austenite. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409008623 [article] Carbon supersaturation of ferrite in a nanocrystalline bainitic steel [texte imprimé] / F. G. Caballero, Auteur ; M. K. Miller, Auteur ; C. Garcia-Mateo, Auteur . - 2011 . - pp. 2338–2343. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 7 (Avril 2010) . - pp. 2338–2343 Mots-clés : Steels  Bainite  Three-dimensional  atom  probe  (3DAP) Résumé : The extremely slow transformation kinetics of a nanocrystalline bainitic steel allows the carbon content of the bainitic ferrite away from any carbon-enriched regions such as dislocations and boundaries to be determined by atom probe tomography as the bainite transformation progresses at 200 °C. A high level of carbon, well above that expected from para-equilibrium with austenite, has been detected in solid solution in bainitic ferrite at the early stage of transformation. Results provide strong evidence that bainite transformation is essentially displacive in nature so that the newly formed bainitic ferrite retains much of the carbon content of the parent austenite. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409008623