Preparation of ultralow thermal conductivity (Mg_0.5Ca_0.3Ba_0.2) (AlSi)₂O₈ceramics

Abstract

A type of nonequimolar multicomponent ceramic solid solution (Mg 0.5 Ca 0.3 Ba 0.2 ) (AlSi) 2 O 8 with a low thermal conductivity was prepared through solid-state synthesis. Results show that the (Mg 0.5 Ca 0.3 Ba 0.2 ) (AlSi) 2 O 8 solid solution exhibits excellent high-temperature stability and an ultralow thermal conductivity (.3676 W m −1 K −1 ), far lower than widely used 3YSZ (2.

Spark plasma sintering of (5RE.2)Ta3O9 high‐entropy ceramics and their thermal properties

“…The conception of high-entropy ceramics (HECs) originates from the high-entropy alloys, which have attracted much attention in recent years and shown many superior performances. [1][2][3][4][5] HECs are usually composed of singlephase solid solutions formed by five or more elements with equimolar or near-isomolar ratios at a certain lattice site of ceramics. Compared with conventional ceramics, HECs often possess many unique properties, such as lower thermal conductivity, [6][7][8] higher hardness, [9][10][11][12] and tunable thermal expansion coefficient, 13,14 and so forth.…”

“…The conception of high‐entropy ceramics (HECs) originates from the high‐entropy alloys, which have attracted much attention in recent years and shown many superior performances 1–5 . HECs are usually composed of single‐phase solid solutions formed by five or more elements with equimolar or near‐isomolar ratios at a certain lattice site of ceramics.…”