Microwave sintering of amorphous silica powders

摘要

Microwave heating (MW) is currently being investigated as a means for densification of porous solids [1-3]. Most of the research concerns crystalline materials. Amorphous materials, which also present considerable scientific and technological interest, are less well studied. The objective of this work was to further study the MW processing of noncrystalline materials by examining the densification of amorphous silica powder compacts heated by exposure to MW fields. Silica bulk gels have already been successfully densified by MW heating [4-7]. The powder compacts, examined here, are markedly more difficult to sinter due to their larger, less uniformly distributed pores, but allow the manufacturing of cheaper and more varied products than gels do.