Processing, microstructure and properties of Nextel™ 610, 650 and 720 fiber/porous mullite matrix composites

Winded high porous oxide ceramic matrix composites (WHIPOX(TM) CMC) are promising candidates for high temperature and long term applications in oxidizing atmospheres. 1D- and 2D - composite have been developed based on highly porous mullite matrices (porosity > 60 vol.% and various oxide fibers such as Nextel(TM) 610, 650 and 720. The composites are fabricated by a computer controlled winding technique using mullite- precursor slurry impregnation of uncoated alumina and alumino silicate fiber yams. Due to the porous matrix, the composites require no fiber coating and exhibit high resistance against thermal shock, excellent non- brittle fracture behavior, and favorable strength up to 1200degreesC.