淀粉为造孔剂制备碳化硅多孔陶瓷

Preparation of Porous SiC Ceramics Using Starch as Pore-forming Agent

以微米碳化硅基体,氧化铝和氧化钇为烧结助剂,淀粉为造孔剂,采用无压烧结技术制备碳化硅多孔陶瓷。通过测试合成多孔陶瓷的密度、收缩率、力学强度以及扫描电子显微镜(SEM)和X-射线衍射(XRD)等研究了不同造孔剂含量对SiC粉体的力学性能、微观形貌和物相的影响。研究表明:随造孔剂含量的升高,碳化硅陶瓷密度和强度降低,气孔率增加,而造孔剂含量对碳化硅陶瓷的物相组成基本没有影响。

Porous SiC ceramics were prepared by pressureless sintering, using silicon carbide micron powder as raw material, alumina and yttria as fluxes and starch as pore-forming agent. Effects of different amounts of pore- forming agent on the mechanical properties, micromorphology and phase composition of SiC powder were analyzed through the tests of the density, shrinkage, mechanical strength of the as-prepared porous ceramics and the characterization by SEM and XRD. Results show： with the increase of the content of pore-forming agent, the density and strength of the SiC ceramics decrease but the porosity increases; the content of pore- forming agent makes no difference to phase composition of SiC ceramics.