Download or read book EVOLUTION STRUCTURALE ET DEFAUTS D IRRADIATION DANS LE COMPOSE INTERMETALLIQUE NI 3AL written by XINC.. ZHANG and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: L'EVOLUTION STRUCTURALE EN FONCTION DE LA TEMPERATURE, LES EFFETS DE L'IRRADIATION PAR DES ELECTRONS ET L'INFLUENCE DE L'ECART A LA STOECHIOMETRIE SUR CES PHENOMENES ONT ETE ETUDIES DANS LE COMPOSE INTERMETALLIQUE NI#3AL, QUI REPRESENTE UN MODELE DE LA PHASE DURCISSANTE DES SUPERALLIAGES A BASE DE NICKEL. DES ALLIAGES MONOPHASES DE TENEUR EN AL COMPRISE ENTRE 24,5 ET 26,4 AT% ONT ETE ETUDIES. DES VARIATIONS REVERSIBLES DE RESISTIVITE ELECTRIQUE MESUREE A 4,2 K, DONT L'AMPLITUDE EST MAXIMALE A LA STOECHIOMETRIE, ONT ETE OBSERVEES LORS DES RECUITS ISOCHRONES ET ONT ETE ATTRIBUEES A UNE EVOLUTION DU DEGRE D'ORDRE A GRANDE DISTANCE DE CES MATERIAUX. LA CINETIQUE DE MISE EN ORDRE A ETE ETUDIEE LORS DE RECUITS ISOTHERMES. LES ALLIAGES NI#3AL ET UN METAL DE REFERENCE (NI) ONT ETE IRRADIES SIMULTANEMENT A 4,6 K PAR DES ELECTRONS DE 3 MEV. SI L'ON ADMET QUE LA CREATION DE DEFAUTS EST LE PHENOMENE PREPONDERANT, ON PEUT DETERMINER LA RESISTIVITE DE LA PAIRE DE FRENKEL (1,15.10##2.CM P.U.C) ET LE VOLUME DE RECOMBINAISON. SI AU CONTRAIRE, ON SUPPOSE QUE LA RESISTIVITE DE LA PAIRE DE FRENKEL EST LA MEME QUE CELLE D'UN ALLIAGE DESORDONNE, ON PEUT OBTENIR LE RAPPORT ENTRE LE NOMBRE DE REMPLACEMENTS ET LE NOMBRE DE DEPLACEMENTS ATOMIQUES (13). LE SPECTRE DE RESTAURATION DANS NI#3AL EST QUALITATIVEMENT SIMILAIRE A CELUI OBTENU DANS LES METAUX PURS; CEPENDANT UNE RESTAURATION SUPERIEURE A 100% INDIQUE QU'UNE MISE EN ORDRE SE PRODUIT AU COURS DES RECUITS. NOUS AVONS DETERMINE LES DOMAINES DE TEMPERATURES OU LES DIFFERENTS DEFAUTS MIGRENT ET S'ELIMINENT

Download or read book MOBILITE ATOMIQUE ET DEFAUTS D IRRADIATION DANS DES PHASES MODELES DE SUPERALLIAGES A BASE DE NICKEL EFFETS DES ADDITIONS DE TITANE ET DE TANTALE written by TAHAR.. TARFA and published by . This book was released on 1994 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: UTILISES DANS L'AEROSPATIALE POUR LEURS EXCELLENTES PROPRIETES MECANIQUES A HAUTE TEMPERATURE, LES SUPERALLIAGES BASE NI SONT CONSTITUES D'UNE PHASE INTERMETALLIQUE DURCISSANTE ORDONNEE A GRANDE DISTANCE (TYPE NI#3AL), DISPERSEE DANS UNE MATRICE DUCTILE ORDONNEE A COURTE DISTANCE (SOLUTION SOLIDE A BASE NI). LEURS PERFORMANCES DEPENDENT DE LA MOBILITE ATOMIQUE ET LES PROPRIETES DES LACUNES. DES SOLUTIONS SOLIDES ET DES COMPOSES INTERMETALLIQUES DU SYSTEME NI-AL-X (X= TI, TA) MODELISANT LES PHASES CONSTITUTIVES DES MATERIAUX INDUSTRIELS ONT ETE ETUDIES. L'EVOLUTION DE L'ORDRE ATOMIQUE EN PRESENCE DE LACUNES D'EQUILIBRE A ETE SUIVIE PAR MESURES DE RESISTIVITE ELECTRIQUE. L'APPLICATION DE LOIS EMPIRIQUES NOUS A PERMIS DE DETERMINER DES CONSTANTES DE TEMPS ET D'EN DEDUIRE DES ENTHALPIES D'AUTODIFFUSION. DANS UNE PARTIE DE CE TRAVAIL NOUS AVONS UTILISE LA SIMULATION MONTE CARLO AFIN D'ABORDER LES CINETIQUES DE MISE EN ORDRE DANS LE SYSTEME NI(AL) D'UN POINT DE VUE ATOMISTIQUE. LA METHODE EST BASEE SUR UN MODELE D'INTERACTION DE PAIRES ET UN MECANISME DE DIFFUSION LACUNAIRE. PAR AILLEURS, DES EXPERIENCES D'IRRADIATION AUX ELECTRONS ONT ETE REALISEES AFIN D'ETUDIER LA PRODUCTION ET LA RESTAURATION DE DEFAUTS PONCTUELS DANS LES DEUX FAMILLES D'ALLIAGES. LES ENTHALPIES D'ACTIVATION ASSOCIEES AUX STADES DE RESTAURATION ONT ETE DETERMINES PAR LA METHODE DE CHANGEMENT DE PENTE. L'ANALYSE DES RESULTATS, EN TERMES DE STRUCTURE ET DE COMPOSITION, REVELE UNE RELAXATION DE L'ORDRE PLUS LENTE ET PLUS COMPLEXE DANS LES COMPOSES INTERMETALLIQUES ET LA PRESENCE DE FORTES INTERACTIONS DES ELEMENTS D'ADDITION (TI ET TA) AVEC LES DEFAUTS PONCTUELS SE TRADUISANT PAR DES EFFETS RALENTISSEURS DE LA MOBILITE ATOMIQUE. CES EFFETS POURRAIENT ETRE A L'ORIGINE DE L'INFLUENCE BENEFIQUE DE CES ELEMENTS SUR LA TENUE A HAUTE TEMPERATURE DES SUPERALLIAGES A BASE DE NICKEL

Download or read book Solidification Processing of Metal Matrix Composites written by Nikhil Gupta and published by Wiley-TMS. This book was released on 2006-11-10 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Solidification Processing of Metal Matrix Composites" (MMCs) focuses primarily on microcomposites but also covers macrocomposites, nanocomposites and foams. There are four main areas detailed: fundamentals of solidification synthesis, which examines issues related to stir mixing, pressure infiltration, transfer of particles or fibers through gas-liquid and liquid-solid interfaces, and particle/fiber interactions with fluids; processing and microstructures, which focuses on microstructure formation during solidification of MMC under different conditions, such as nucleation, growth, heat transfer, microsegregation, macrosegregation and interactions between solidifying interfaces, particles and fibers; and, properties of solidification processing, covering the relationship between the microstructures and properties. Comparisons are made between properties of solidification processed composites and monolithic and composites made by solid and vapor phase processes. It also details the application of solidification processed MMCs, revealing current and future applications especially in automotive, aerospace, railroad, thermal management, electromechanical machinery and recreational equipment sectors.

Download or read book Simulation of Aluminum Shape Casting Processing written by Qigui Wang and published by Wiley-TMS. This book was released on 2006-11 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the latest developments and applications of modeling and simulation techniques in aluminum shape castings, and the need for improvement of these computational techniques. Specifically, topics include design of both the cast aluminum alloy as well as aluminum casting and gating system; modeling, simulation and optimization of both the casting process and heat treatment; modeling and simulation of both casting defect and microstructure; prediction of mechanical performance and influence of subsequent processing on final performance. Developers and users of computational techniques applied to aluminum shape castings as well as end users of castings will find this book extremely helpful.

Download or read book Materials Processing Fundamentals written by Lifeng Zhang and published by Springer. This book was released on 2016-12-01 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection provides researchers and industry professionals with complete guidance on the synthesis, analysis, design, monitoring, and control of metals, materials, and metallurgical processes and phenomena. Along with the fundamentals, it covers modeling of diverse phenomena in processes involving iron, steel, non-ferrous metals, and composites. It also goes on to examine second phase particles in metals, novel sensors for hostile-environment materials processes, online sampling and analysis techniques, and models for real-time process control and quality monitoring systems.

Download or read book Materials Design Approaches and Experiences written by Ji-Cheng Zhao and published by Minerals, Metals, & Materials Society. This book was released on 2001 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: These papers describe past alloy design experiences and state-of-the-art methodologies and first-principle, neural network, combinational, phase-field, thermodynamic, and regression-based alloy design.

Download or read book Advanced Materials for Energy Conversion III written by Dhanesh Chandra and published by Wiley-TMS. This book was released on 2006-11 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: A collection of proceedings from the symposium in Honor of Drs. Gary Sandrock, Louis Schlapbach, and Sejiirau Suda. From the a href="http: //www.tms.org/Meetings/Annual-06/AnnMtg06Home.html"2006 TMS Annual Meeting, held March 12-16, 2006, in San Antonio, Texas.