ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The preparation of β-SiMONs by the thermal treatment (1373–1773 K) under nitrogen of various mixtures of clays and organic molecules (acrylonitrile) or carbon (charcoal) or graphitic oxide, was investigated. Cation (Na+, Y3+, C6-amine+) exchanged smectites (montmorillonite or hectorite) and kaolinite were used. With charcoal mixtures, a threshold of carbon content was found for each clay in the formation of β-SiMONs: 23% for montmorillonite, 14% for hectorite and 21% for kaolinite. This threshold was not reached in the case of polyacrylonitrile or graphitic oxide-smectite precursors and carboreduction under nitrogen of these precursors did not yield β-SiMONs. The thermal evolution of the carbon phases at low temperature, before contact with clays, influenced the formation of β-SiMONs which appears at 1673 K if the carbon content is greater than the threshold, but always with other minor phases.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01117934
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