The structure and thermophysical properties of materials formed in the Dy 2 O 3 -HfO 2 system (molar ratio from 1: 3 to 3: 1 ) as a result of isothermal roasting of X-ray amorphous mixed hydroxides at temperatures up to 1600 C. It has been shown that, at a ratio of 1: 3 to 1: 1, the crystallization process leads to the formation of single-phase solid solutions having the structure of defective fluorite with a pronounced nonequivalence of the parameters of the local environment of Dy and Hf. It was found that ceramics based on dysprosium hafnate (Dy 2 O 3 : HfO 2 = 1: 1) has a low thermal conductivity ~ 1.4 W / (m • K), practically independent of temperature (up to 800 С)
Dr. chem. Sciences V. V. POPOV
1 (
e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it. ), Dr. Sciences A. P. MENUSHENKOV
1 ,
Dr. of Phys.-Math. Sciences Y. V. ZUBAVICHUS
2 , S. A. KOROVIN
1 , Cand. chem. Sciences E. A. FORTALNOVA
3 ,
Cand. physical-mat. A. B. KRUGLOV
1 , Cand. tech. Sci. V. B. KRUGLOV
1 , E. S. KULIK
2 , Dr. of Phys.-Math. Sciences A. A. PISAREV
1
;
1 National Research Nuclear University "MEPhI" (NRNU MEPhI) (Russia, Moscow)
2 NRC "Kurchatov Institute" (Russia, Moscow)
3 Peoples' Friendship University of Russia (Russia, Moscow)
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