کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7922907 | 1511801 | 2015 | 10 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
The effect of niobium- and tantalum oxide on nucleation and growth kinetics in lithium disilicate glasses
ترجمه فارسی عنوان
اثر نایوبیم و اکسید تانتالوم بر روی سینتیک هسته ای و رشد در عینک های لیتیوم دیزلیکت
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
مواد غیر بلوری، هسته، رشد کریستال، میکروسکوپ نوری،
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی مواد
مواد الکترونیکی، نوری و مغناطیسی
چکیده انگلیسی
Stoichiometric lithium disilicate glasses were doped with up to 2Â mol% Nb2O5 or Ta2O5. The additives led to an increase in viscosities and to a change in the crystallization behavior. The steady-state nucleation rates, the induction times and the crystal growth velocities were studied as a function of the temperature using in situ optical hot stage microscopy. While the nucleation rates decrease by up to three orders of magnitude, the induction times significantly increase. The effect of nucleation inhibition is not solely based on higher viscosities. It is assumed that the glasses consists of SiO4 tetrahedra and MO6 (MÂ =Â Nb, Ta) octahedra and hence, with increasing additive concentration, the structural similarities between glass and lithium disilicate crystal decrease leading to smaller nucleation rates. Moreover, the crystal growth velocities decrease drastically. Optical micrographs indicate a lamellar growth proceeding from the crystal center. During growth, the lithium disilicate crystals get a constriction in their center leading to a dumbbell-like shape.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Materials Chemistry and Physics - Volume 162, 15 July 2015, Pages 354-363
Journal: Materials Chemistry and Physics - Volume 162, 15 July 2015, Pages 354-363
نویسندگان
Katrin Thieme, Christian Rüssel,