Dual sacrificed templating of porous silicon carbide ceramics with hierarchical structure

作者：Luo, Min^*; Hou, Guang-Ya; Liang, Sen; Lv, Yu-Qin; Ma, Yong-Hua; Li, Xing

来源：Journal of Synthetic Crystals, 2013, 42(4): 664-670.

• Direct foaming
• Freeze casting methods
• Hierarchical pore structures
• Hierarchical structures
• Hierarchically porous
• Porous SiC
• Sacrificial templates
• Spherical pores

Hierarchically porous SiC ceramics were fabricated by combined freeze-casting method with direct foaming method using dual sacrificial template technique. The influences of SiC solid content and the size of polystyrene (PS) microspheres on pore morphology, porosity and compressive strength of porous SiC ceramics were investigated. The porous SiC had a unique microstructure, where aligned interconnected lamellar pores and spherical pores distributed in the internal walls of SiC matrix. The aligned large pores were generated by sublimation of ice template and the spherical pores were caused by decomposing the PS microspheres. The pore structure was controlled by selecting the solid content of SiC slurry, content and size of PS microspheres. As the solid content of SiC slurry increasing, the size and pore volume of large lamellar pore decreased, but the compressive strength increased. The size of spherically intermediate pores increased with the increasing the size of PS microspheres.

• 出版日期2013-4
• 单位浙江大学