Электронный каталог

Статья

Maletskii, A.V.
Influence of Stabilized Zirconium Dioxide and High Hydrostatic Pressure on the Kinetics of Sintering Nanopowders of Metastable Aluminum Oxide / A.V.Maletskii, A.S.Doroshkevich, A.A.Tatarinova, [et al.] // Ceramics International [Electronic resource]. – 2024. – Vol. 50, No. 22, Pt. B. – P. 46506-46515. – URL: https://doi.org/10.1016/j.ceramint.2024.09.002. – Bibliogr.: 38.

The paper presents an analysis of the effect of processing powders with high hydrostatic pressure (HHP) (300, 500, 700 MPa) and stabilized zirconium dioxide (ZrO&sub(2) + 3 mol.% Y&sub(2)O&sub(3), (YSZ)) doping on the compaction of metastable nanopowders mixture with *g+*y-Al&sub(2)O&sub(3) + n% YSZ (n = 0, 1, 5, 10, 15 wt%) composition during sintering. The behavior of nanopowders at the initial stage of sintering was studied by dilatometry at a constant heating rate of 5 &sup(o)C/min, in temperature range from 20 &sup(o)C to 1500 &sup(o)C. It has been determined that sintering of compacts occurs in two stages: compaction of *g + *y-Al&sub(2)O&sub(3) (I-st stage metastable phases), compaction of the stable α-Al&sub(2)O&sub(3) (II-nd stage), accompanied by inhibition between them. An “effect of mutual protection against crystallization” of powder mixtures was determined using the X-ray diffraction method. This is characteristic of systems obtained by co-precipitation. A connection between the above mentioned inhibition and an increase in the YSZ additive was found. That, also, correlates to the effect of “mutual protection against crystallization” of Al2O3 – YSZ powder mixtures. A study of the mechanisms and activation energies of *g+-*y-Al&sub(2)O&sub(3) + n% YSZ systems’ (n = 0, 1, 5, 10, 15 wt%) sintering depending on the YSZ additive amount and the HHP value showed that a dopant and pressure increase leads to activation energy decrease of the initial sintering stage, and the prevailing sintering mechanism is volumetric diffusion in corundum grains. Also, the work shows that for *g+*y-Al&sub(2)O&sub(3) + ≥5 wt% YSZ systems, the optimal compaction pressure is HHP ≥500 MPa, which corresponds to the transition of the sintering mechanism from grain-boundary diffusion to volumetric diffusion



ОИЯИ = ОИЯИ (JINR)2024
Спец.(статьи,препринты) = С 36 - Физика твердого тела$
Спец.(статьи,препринты) = С 332.8 - Синхротронное излучение. Лазеры на свободных электронах. Получение и использование рентгеновских лучей
Спец.(статьи,препринты) = С 33 а - Нанофизика. Нанотехнология$
Спец.(статьи,препринты) = С 44 г - Физико-химические методы анализа элементов. Анализ с помощью ядерных методов
Бюллетени = 49/024