کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5438143 1398181 2017 27 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Improved transparency and hardness in α-alumina ceramics fabricated by high-pressure SPS of nanopowders
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Improved transparency and hardness in α-alumina ceramics fabricated by high-pressure SPS of nanopowders
چکیده انگلیسی
Nanocrystalline alumina powder with an average crystallite size of ≤50 nm has been consolidated by spark plasma sintering (SPS) and hot pressing (HP) with a view to achieving dense, fine grained alumina bodies that display transparency. When as-synthesised powder was densified directly, excessive grain growth resulted from both the SPS and HP techniques and hence a large final grain size was observed. Attempts to improve the uniformity of the green microstructure prior to densification were unsuccessful when spray freeze dried granules were used, whether pre-pressed into a compact or not. The use of 53% dense slip cast green compacts, however, enabled final density of ~99.96% and a mean grain size of ~0.32 µm to be achieved when SPS conditions of 1200 °C and 500 MPa were applied for 20 min. These samples offered in-line transmittance values of up to ~80% and microhardness values of 22 GPa.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ceramics International - Volume 43, Issue 1, Part A, January 2017, Pages 275-281
نویسندگان
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