Effects of Al2O3 addition on the sintering behavior and microwave dielectric properties of CaSiO3 ceramics

Effect of TiO2 Doping on the Structure and Microwave Dielectric Properties of Cordierite Ceramics

“…Moreover, in silicate structures, Al 3+ ions would like to occupy the Si 4+ ionic sites to compose the [AlO 4 ] tetrahedrons with a negative charge vacancy. Some silicates such as Cristobalite (SiO 2 ), Forsterite (Mg 2 SiO 4 ), Pyroxene (CaMgSi 2 O 6 ), Sr‐Gehlenite (Sr 2 Al 2 SiO 7 ), Anorthite (CaAl 2 Si 2 O 8 ), Sr‐Feldspar (SrAl 2 Si 2 O 8 ), Willemite (Zn 2 SiO 4 ), Cordierite (Mg 2 Al 4 Si 5 O 18 ), Apatite‐type [LiRe 9 (SiO 4 ) 6 O 2 ] (Re = rare earth elements), Mullite (Al 6 Si 2 O 13 ), etc., are the alternative candidates for microwave and millimeter‐wave dielectric materials, which have been fabricated and reported during the recent years.…”

Preparation of Al2O3‐mullite thermal insulation materials with AlF3 and SiC as aids by microwave sintering

“…Since the different dielectric losses for various materials, the absorption efficiency for microwaves possess significant difference. At the initial heating stage, Al 2 O 3 particles hardly absorb microwave due to its low dielectric losses at room temperature 20,21 . Only SiC particles could absorb microwave energy so that the isolated hot spots appear within the samples and local temperature was increased 18 .…”

“…At the initial heating stage, Al 2 O 3 particles hardly absorb microwave due to its low dielectric losses at room temperature. 20,21 Only SiC particles could absorb microwave energy so that the isolated hot spots appear within the samples and local temperature was increased. 18 With the increasing of input power, local temperature was instantaneously increased.…”

“…[12][13][14][15][16][17][18][19] Nevertheless, few researchers use microwave heating to prepare porous Al 2 O 3 ceramics, because the dielectric loss of Al 2 O 3 particle is relatively low at low temperatures so that it is difficult to couple with microwave to raise the temperature. 20,21 This work provides a method to solve this problem. Since SiC has a relatively significant dielectric loss and can be coupled with microwave to generate heat, a few amounts of SiC particles have been induced as a hot spot to raise the temperature.…”

“…The unique heating behavior helps to reduce heating temperature and heating time, as well as to improve the microstructure of the samples 12–19 . Nevertheless, few researchers use microwave heating to prepare porous Al 2 O 3 ceramics, because the dielectric loss of Al 2 O 3 particle is relatively low at low temperatures so that it is difficult to couple with microwave to raise the temperature 20,21 . This work provides a method to solve this problem.…”