The corrosion resistance of chemically modified β-eucryptite (Li<sub>0.41</sub>Mg<sub>0.035</sub>AlP<sub>0.52</sub>Si<sub>0.48</sub>0₄) having low expansion anisotropy and a near zero coefficient of thennal expansion was evaluated. Samples were exposed to aqueous hydrochloride acid at temperatures up to 100°C and environments containing sodium sulfate up to l000°C. The corrosion resistance was characterized by dilatometry, scanning electron microscopy, X-ray diffraction, energy dispersive x-ray analysis, weight variations, and mechanical properties variations.
The results show that modified β-eucryptite is more severely corroded than commercial lithium-alumina-silicate glass-ceramics when exposed to these environments. Aqueous HCI removes AIP04 from modified β-eucryptite leaving a very porous structure. Molten salt corrodes modified β-eucryptite by penetration of sodium and sulfur which form an alkali melt under the surface. The modulus of rupture and the Young's modulus are reduced by both types of corrosion. / Master of Science
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/44206 |
| Date | 14 August 2009 |
| Creators | Battu, Laurent P. |
| Contributors | Materials Engineering, Brown, Jesse J. Jr., Gordon, Ronald S., Farkas, Diana |
| Publisher | Virginia Tech |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Thesis, Text |
| Format | xi, 69 leaves, BTD, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | OCLC# 24344529, LD5655.V855_1991.B388.pdf |
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