陶瓷微珠直接堆烧制备多孔莫来石陶瓷及性能研究

以高纯石英粉、氧化铝粉以及玻璃粉作为主要原料,首先通过颗粒稳定泡沫法结合离心雾化干燥装置制备得到SiO2-Al2O3陶瓷微珠,然后将其紧密堆积于坩埚中,随后经1500 ℃下直接堆积烧结1 h,利用空心微珠高温下自发泡,成功制备孔分布均匀的多孔莫来石陶瓷.研究了SiO2-Al2O3陶瓷微珠中高纯石英粉、氧化铝粉和玻璃粉组成对多孔莫来石陶瓷性能的影响.该方法简便易行,可控性强.通过该方法可制得气孔率高达85.4;,抗压强度为(3.69±0.86) MPa,低介电常数为1.70的多孔莫来石陶瓷,有望应用于透波材料领域.

Fabrication and Properties of Porous Mullite Ceramics from Directly Sintering Ceramic Microspheres

SiO2-Al2O3 ceramic microspheres were fabricated by particle-stabilized foams method combining with centrifugal spray drying process, where high purified quartz powder, alumina powder and glass powder were chosen as raw materials.Then, SiO2-Al2O3 ceramic microspheres were closely packed in the crucible, followed by directly sintering at 1500 ℃ for 1 h and porous mullite ceramics with well distributed pores were prepared through self-foaming process at elevated temperature.The effect of raw materials compositions on the properties of porous mullite ceramics has been studied.This novel method is simple, convenient, and controllable.Porous mullite ceramics with high porosity of 85.4%, compressive strength of (3.69±0.86) MPa, and low dielectric constant of 1.70 was obtained by this method which could be applied to the wave-transparent materials field.