碳化硅多孔陶瓷气孔率和强度影响因素

Influence Factors on the Porosity and Strength of SiC Porous Ceramic

研究了陶瓷粘结剂含量、碳化硅颗粒粒径以及烧结温度对高温气体过滤用碳化硅多孔陶瓷抗弯强度和气孔率的影响.利用X射线衍射测试了多孔陶瓷烧结后的物相组成.陶瓷粘结剂含量的增加使碳化硅多孔陶瓷的气孔率快速下降,在陶瓷粘结剂含量15wt%时,碳化硅多孔陶瓷可具有较高的气孔率(37.5%)和抗弯强度(27.63MPa).随着碳化硅颗粒粒径从300μm减少到87μm,碳化硅多孔陶瓷的气孔率和抗弯强度可同时提高,气孔率从35.5%增加到了42.4%,而抗弯强度从19.92MPa增加到了25.18MPa.碳化硅多孔陶瓷的烧结温度从1300℃增加到1400℃过程中,其气孔率从38.7%迅速下降到35.4%,而其抗弯强度一直在27MPa左右,没有大幅变化,所以该多孔陶瓷的烧结温度应该选在陶瓷粘结剂熔点(1300℃)附近,不宜过高.

The influence of ceramic binder contents,SiC particle sizes,and sintering temperatures on the porosity and flexural strength of SiC porous ceramics for high-temperature gas filtration were investigated.The composition of SiC porous ceramics was measured by X-ray diffraction.The porosity of SiC porous ceramics decreased with increasing the ceramic binder contents,and the SiC porous ceramic with a relatively high porosity of 37.5% and flexural strength of 27.63MPa was obtained with ceramic binder content of 15wt%.Both the porosity and flexural strength of SiC porous ce-ramics increased with SiC particle sizes decreasing from 300μm to 87μm,and the porosity increased from 35.5% to 42.4%,while the flexural strength increased from 19.92MPa to 25.18MPa.In addition,the porosity of SiC porous ceram-ics quickly decreased from 38.7% to 35.4% with sintering temperatures increasing from 1300℃ to 1400℃,but the flex-ural strength of SiC porous ceramics had only a slight change,mainly standing at about 27MPa.Thus,the sintering tem-perature of SiC porous ceramics should be selected around the melting point of ceramic binder（1300℃）.