摘要
选用SiC颗粒作为多孔陶瓷的骨料材料,长石、石英、粘土组成的低共熔混合物形成晶界玻璃相结合剂,活性炭作为成孔剂,采用注浆成型工艺,对多孔陶瓷的性能进行了研究.SiC骨料颗粒的Zeta电位等电点对应的pH值为5.2,注浆浆料的pH值在8～12的范围内具有很好的流动性和稳定性;烧成温度的提高,使SiC多孔陶瓷的气孔尺寸分布范围缩小,但基本孔径不变;晶界玻璃相的高温粘性流动在SiC晶粒之间形成“桥架”结构,提高了两者之间的粘结能力;高温下,SiC颗粒的氧化产物参与晶界反应,生成新的针状莫来石相,使SiC多孔陶瓷的强度出现异常提高.
The silicon carbide particles were employed as the skeleton material, while the mixture of feldspar and clay in eutectic composition to form the glassy grain-boundary phase serving as the binder to hold the Sic grains together, particulate carbon to be oxidized and generate pores. Slip casting process was investigated and some properties of the porous ceramics were discussed. The isoelectric Zeta potential point of the Sic particles corresponded to the pH value of 5.2, and the pH values of the slurry were controlled between 8 and 12 to provide the perfect stability and fluidity. The increase in the firing temperature decreases the range of the pore size distribution, with the principal pore diameter keeps relatively constant. The neck-bridging structure exists among the Sic grains due to the viscous flow of the grain-boundary phase at high temperatures, which helps to improve the binding behaviour. The oxidation product of Sic reacts with the grain-boundary,phase, and leads to the precipitation of needle-like mullite crystals, which gives rise to the abnormal increase in the strength of the porous ceramics.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2002年第4期725-730,共6页
Journal of Inorganic Materials
基金
清华大学新型陶瓷和精细工艺国家重点实验室基金资助(XGZ9910)
河南省自然科学基金
河南省模具
材料工程及装备重点实验室基金
