کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1476164 991144 2012 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Grain boundary glasses in silicon nitride: A review of chemistry, properties and crystallisation
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Grain boundary glasses in silicon nitride: A review of chemistry, properties and crystallisation
چکیده انگلیسی

Silicon nitride for engineering applications is densified by liquid phase sintering using oxide additives such as yttria and alumina. The oxynitride liquid remains as an intergranular glass. This paper provides a review of microstructural development in silicon nitride, grain boundary oxynitride glasses and effects of chemistry on properties. Nitrogen increases Tg, viscosities, elastic moduli and microhardness. These property changes are compared with known effects of grain boundary glass chemistry in silicon nitride ceramics where significant improvements in fracture resistance of silicon nitride can be achieved by tailoring the intergranular glass chemistry.Crystallisation of the grain boundary Y–Si–Al–O–N glass phase can improve properties. Nucleation and crystallisation of a Y–Si–Al–O–N glass, similar to that found in grain boundaries of silicon nitride densified with yttria and alumina, can be optimised to form different Y-disilicate polymorphs at different temperatures. One solution to provide a single disilicate phase over a range of temperatures is discussed.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of the European Ceramic Society - Volume 32, Issue 9, July 2012, Pages 1925–1932
نویسندگان
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