Abstract
The interaction between SiO2 (vitreous/fused silica and quartz) and Mg powder at 450-640 °C was investigated employing a combination of X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy. The interaction resulted in the formation of a periodic layered structure, consisting of alternating MgO and Mg2Si-rich layers, with typical thickness of 0.5-3 μm. The reaction zone was found to grow by a parabolic law with activation energy of about 76 and 90 kJ/mol for fused silica/Mg and quartz/Mg interactions, respectively. The growth process is controlled by Mg diffusion to SiO2 substrate. A qualitative model describing the formation of such a layered structure in the SiO2/Mg system is presented.
Original language | English |
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Pages (from-to) | 4677-4684 |
Number of pages | 8 |
Journal | Acta Materialia |
Volume | 54 |
Issue number | 18 |
DOIs | |
State | Published - Oct 2006 |
Externally published | Yes |
Keywords
- Activation energy
- Diffusion couple
- Magnesium
- Periodic layer formation
- Silicon oxide