Interfacial reaction and the dominant diffusing species in Mg-Ni system
Journal
Journal of Alloys and Compounds
Journal Volume
471
Journal Issue
1-2
Pages
90-92
Date Issued
2009
Author(s)
Abstract
The solid-solid interfacial reaction in the Mg-Ni binary diffusion couples was studied for the first time in bulk form. The reaction temperature was at 400, 430, 450, and 480 °C, with reaction time ranging from 10 to 75 h. The Mg-Ni phase diagram shows two stable compounds, Mg2Ni and MgNi2, at these temperatures, but only Mg2Ni was observed at the interface after the reaction. The growth of Mg2Ni followed the parabolic kinetics, and the apparent activation energy was determined to be 120 kJ/mol. The dominant diffusing species was identified by using thin W lines as markers. After the reaction, these W markers located near the Mg/Mg2Ni interface, suggesting that Mg was the dominant diffusing species in Mg2Ni. This is consistent with the general trend that in many metal/metal systems the dominant diffusing species are usually the majority elements in the compounds that formed first. © 2008 Elsevier B.V. All rights reserved.
Type
journal article