najoNanosystems: Physics, Chemistry, MathematicsНаносистемы: физика, химия, математика2220-80542305-7971Университет ИТМО10.17586/2220-8054-2021-12-6-799-807najo-579Research ArticleCHEMISTRY AND MATERIALS SCIENCEХИМИЯ И НАУКА О МАТЕРИАЛАХThe influence of condition of the monazite structured La0.9Y0.1PO4 nanocrystals sintering on thermal and mechanical properties of the materialВлияние условий спекания нанокристаллов La0.9Y0.1PO4 со структурой монацита на термические и механические свойства материалаEnikeevaM. O.EnikeevaM. O.

26, Politekhnicheskaya St., 194021, St. Petersburg;

26, Moskovsky Ave., 190013, St. Petersburg.

enikeevamo@gmail.comProskurinaO. V.ProskurinaO. V.

26, Politekhnicheskaya St., 194021, St. Petersburg;

26, Moskovsky Ave., 190013, St. Petersburg.

MotayloE. S.MotayloE. S.

26, Moskovsky Ave., 190013, St. Petersburg.

DanilovichD. P.DanilovichD. P.

26, Moskovsky Ave., 190013, St. Petersburg.

GusarovV. V.GusarovV. V.

26, Politekhnicheskaya St., 194021, St. Petersburg.

Ioffe Institute; Saint Petersburg State Institute of TechnologyRussian FederationSaint Petersburg State Institute of TechnologyRussian FederationIoffe InstituteRussian Federation202107082025126799807Copyright © Enikeeva M.O., Proskurina O.V., Motaylo E.S., Danilovich D.P., Gusarov V.V., 20252025Enikeeva M.O., Proskurina O.V., Motaylo E.S., Danilovich D.P., Gusarov V.V.Enikeeva M.O., Proskurina O.V., Motaylo E.S., Danilovich D.P., Gusarov V.V.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://nanojournal.ifmo.ru/jour/article/view/579

A lanthanum orthophosphate- and yttrium-based monazite structured La0.9Y0.1PO4 nanocrystalline material was synthesized. The influence of the thermal treatment temperature on its thermal and mechanical properties has been determined. It was shown that the hydrothermal treatment of coprecipitated phosphates at 230 ◦C for 110 minutes yielded monazite structured nanoparticles with the crystallite size of about 16 nm. Nanopowder thermal treatment for 20 min in the annealing-quenching mode at 1000–1400 ◦C resulted in obtaining compact materials, the porosity of which varied from 52 to 27% with the grain growth from ∼20 to ∼100 nm. Active sintering occurred at temperatures above 1300 ◦C. Nanocrystalline materials obtained by heat treatment at 1200 ◦C with a grain size of ∼40 nm have a porosity of 42%, microhardness of Hv(25 ◦C) = 4±0.5 GPa, thermal conductivity λ(25 ◦C) = 0.4 W·m−1·K−1, and can be used as thermal insulation material.

Синтезирован нанокристаллический материал на основе ортофосфатов лантана и иттрия La0.9Y0.1PO4 со структурой монацита. Определено влияние температуры обработки на его термические и механические свойства. Показано, что при гидротермальной обработке соосажденных фосфатов при 230 °С в течение 110 минут образуются наночастицы со структурой монацита с размером кристаллитов около 16 нм. Термическая обработка нанопорошков в течение 20 мин в режиме отжиг-закалка при 1000–1400 °С привела к получению компактных материалов, пористость которых варьировалась от 52 до 27 % при росте зерен от ~20 до ~100 нм. Активное спекание происходило при температурах выше 1300 °С. Нанокристаллические материалы, полученные термообработкой при 1200 °С с размером зерна ~40 нм, имеют пористость 42 %, микротвердость Hv(25°С) = 4±0.5 ГПа, теплопроводность λ(25°С) = 0.4·м-1·К-1, и может использоваться в качестве теплоизоляционного материала.

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The authors declare that there are no conflicts of interest present.