Documents disponibles écrits par cet auteur

Effect of particle size in aggregated and agglomerated ceramic powders / A. Balakrishnan in Acta materialia, Vol. 58 N° 3 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 802-812 Titre : Effect of particle size in aggregated and agglomerated ceramic powders Type de document : texte imprimé Auteurs : A. Balakrishnan, Auteur ; P. Pizette, Auteur ; C. L. Martin, Auteur Article en page(s) : pp. 802-812 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Ceramics  Powder  consolidation  Molecular  dynamics  simulations  Aggregates  Agglomerates Index. décimale : 669 Métallurgie Résumé : This work describes the compaction of agglomerated and aggregated ceramic powders with special emphasis on the role of primary particle size. Discrete element simulations are used to model weakly bonded agglomerates as well as strongly bonded aggregates. Crushing tests are carried out to obtain the characteristic strength of single agglomerate and aggregate. Microstructure evolution and stress–strain curves indicate that aggregates undergo a brittle to plastic-like transition as particle size decreases below 50 nm. It is shown that agglomerates made of nanoparticles exhibit much greater strength than those made of micron-sized particles, with an approximately inverse linear relationship with primary particle size. Simulation of the uniaxial compaction of a representative volume element of powder demonstrates that adhesive effects are responsible for the difficulty to compact nanopowders and for the heterogeneity of microstructure prior to sintering. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%23 [...] [article] Effect of particle size in aggregated and agglomerated ceramic powders [texte imprimé] / A. Balakrishnan, Auteur ; P. Pizette, Auteur ; C. L. Martin, Auteur . - pp. 802-812. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 802-812 Mots-clés : Ceramics  Powder  consolidation  Molecular  dynamics  simulations  Aggregates  Agglomerates Index. décimale : 669 Métallurgie Résumé : This work describes the compaction of agglomerated and aggregated ceramic powders with special emphasis on the role of primary particle size. Discrete element simulations are used to model weakly bonded agglomerates as well as strongly bonded aggregates. Crushing tests are carried out to obtain the characteristic strength of single agglomerate and aggregate. Microstructure evolution and stress–strain curves indicate that aggregates undergo a brittle to plastic-like transition as particle size decreases below 50 nm. It is shown that agglomerates made of nanoparticles exhibit much greater strength than those made of micron-sized particles, with an approximately inverse linear relationship with primary particle size. Simulation of the uniaxial compaction of a representative volume element of powder demonstrates that adhesive effects are responsible for the difficulty to compact nanopowders and for the heterogeneity of microstructure prior to sintering. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%23 [...]

Effect of particle size in aggregated and agglomerated ceramic powders / A. Balakrishnan in Acta materialia, Vol. 58 N° 3 (Fevrier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 802–812 Titre : Effect of particle size in aggregated and agglomerated ceramic powders Type de document : texte imprimé Auteurs : A. Balakrishnan, Auteur ; P. Pizette, Auteur ; C. L. Martin, Auteur Année de publication : 2011 Article en page(s) : pp. 802–812 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Ceramics  Powder  consolidation  Molecular  dynamics  simulations  Aggregates  Agglomerates Résumé : This work describes the compaction of agglomerated and aggregated ceramic powders with special emphasis on the role of primary particle size. Discrete element simulations are used to model weakly bonded agglomerates as well as strongly bonded aggregates. Crushing tests are carried out to obtain the characteristic strength of single agglomerate and aggregate. Microstructure evolution and stress–strain curves indicate that aggregates undergo a brittle to plastic-like transition as particle size decreases below 50 nm. It is shown that agglomerates made of nanoparticles exhibit much greater strength than those made of micron-sized particles, with an approximately inverse linear relationship with primary particle size. Simulation of the uniaxial compaction of a representative volume element of powder demonstrates that adhesive effects are responsible for the difficulty to compact nanopowders and for the heterogeneity of microstructure prior to sintering. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409006648 [article] Effect of particle size in aggregated and agglomerated ceramic powders [texte imprimé] / A. Balakrishnan, Auteur ; P. Pizette, Auteur ; C. L. Martin, Auteur . - 2011 . - pp. 802–812. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 3 (Fevrier 2010) . - pp. 802–812 Mots-clés : Ceramics  Powder  consolidation  Molecular  dynamics  simulations  Aggregates  Agglomerates Résumé : This work describes the compaction of agglomerated and aggregated ceramic powders with special emphasis on the role of primary particle size. Discrete element simulations are used to model weakly bonded agglomerates as well as strongly bonded aggregates. Crushing tests are carried out to obtain the characteristic strength of single agglomerate and aggregate. Microstructure evolution and stress–strain curves indicate that aggregates undergo a brittle to plastic-like transition as particle size decreases below 50 nm. It is shown that agglomerates made of nanoparticles exhibit much greater strength than those made of micron-sized particles, with an approximately inverse linear relationship with primary particle size. Simulation of the uniaxial compaction of a representative volume element of powder demonstrates that adhesive effects are responsible for the difficulty to compact nanopowders and for the heterogeneity of microstructure prior to sintering. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409006648