Nucleation and growth of β′magnesium sialons and their composition limits
| ISSN: |
1573-4803
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| Source: |
Springer Online Journal Archives 1860-2000
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| Topics: |
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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| Notes: |
Abstract Previous reports on the solubility of magnesium in β′-sialons have been conflicting. The present work shows conclusively that crystalline magnesium sialons with the β silicon nitride structure do exist. They are formed by crystallization of magnesium sialon glasses at low temperatures. β″-magnesium sialon crystals nucleate on β′-sialon nuclei which are themselves formed by precipitation from Mg-Si-Al-O-N liquids at high temperatures. The current results suggest that β″-magnesium sialons exist only over a limited composition range within the 3M/4X plane of the Mg-Si-Al-O-N system, which is indicative of some form of ordering within the β″ structure. Although the compositions investigated in the present study are unstable with respect to forsterite above about 1000° C, the possibility of producing β″-magnesium sialons which are stable at much higher temperatures cannot be fully discounted at present.
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| Type of Medium: |
Electronic Resource
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| URL: |