High-strength thermal insulating porous mullite fiber-based ceramics

How to improve the strength of fibrous porous ceramics dramatically under the premise of no sacrificing its low density and thermal conductivity has remained a challenge in the high-temperature thermal insulation field. In this paper, a new kind of high-strength mullite fiber-based ceramics composed of interlocked porous mullite fibers was prepared by nanoemulsion electrospinning and dry pressing method. Results show that as to the porous ceramics with the same density (similar to 0.8 g/cm(3)), the three-dimensional skeleton structure composed of porous mullite fibers was much denser than that composed of solid mullite fibers. Therefore, porous mullite fiber-based ceramics exhibited a higher compressive strength (5.53 MPa) than that of solid mullite fiber-based ceramics (3.21 MPa). In addition, porous mullite fiber-based ceramics exhibited a superior high-temperature heat insulation property because the porous structure in fibers could reduce the radiant heat conduction. This work provides new insight into the development of high-temperature thermal insulators.

Automated summary

This study presents a new approach to dramatically improve the strength of fibrous porous ceramics while maintaining low density and thermal conductivity. By using nanoemulsion electrospinning and dry pressing method, high-strength mullite fiber-based ceramics composed of interlocked porous mullite fibers were prepared. The results show that the porous ceramics exhibited a higher compressive strength than solid ceramics due to the denser three-dimensional skeletal structure composed of porous mullite fibers. Moreover, the porous structure in the fibers also contributed to superior high-temperature heat insulation, providing new insights into the development of thermal insulators.