Interfacial reactions in Al-Mg (5083)/AI2O3p composites during fabrication and remelting

Autor:	Gilles L'Espérance, W.M. Zhong, M. Suéry
Rok vydání:	1995
Předmět:	Chemical kinetics Reaction rate Materials science Electron diffraction Mechanics of Materials Transmission electron microscopy Scanning electron microscope Metallurgy Metals and Alloys Metallography Grain boundary Condensed Matter Physics Chemical reaction
Zdroj:	Metallurgical and Materials Transactions A. 26:2625-2635
ISSN:	1543-1940 1073-5623
DOI:	10.1007/bf02669420
Popis:	The interface reactions between a-Al2O3 particles and 5083 Al-Mg alloys during fabrication by compocasting and subsequent remelting at 800 °C for 30 minutes have been studied using analytical transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Experimental results show that MgO is the main reaction compound produced by the reaction 3Mg (1) + A12O3 (s) = 3MgO (s) + 2A1 (1). The MgO crystals formed by interfacial reaction are very small (about 5 to 20 run in diameter), and the reaction zone is about 50 to 80-nm wide for as-cast materials and about 100 to 150 nm after remelting. The reaction kinetics is controlled by seepage of Mg and release of Al (1) along the newly formed MgAl2O4 or MgO grain boundaries. Because of the large volume expansion during the formation of MgO from the reaction between Mg (1) and A12O3 and because of the low diffusivity in MgO crystals, the reaction rate is very low.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::3aa915023d8e819733df4fe4afccf61c https://doi.org/10.1007/bf02669420 Zobrazit plný text záznamu Full text from SpringerLink