Journal of the American Ceramic Society, Vol.86, No.9, 1628-1630, 2003
Combined spectroscopic and thermodynamic investigation of nextel-720 fiber/alumina ceramic-matrix composite in air and water vapor at 1100 degrees C
The high-temperature performance of a Nextel-720 fiber/Al2O3 composite in air and water vapor at 1100degreesC was investigated using X-ray photoelectron spectroscopy (XPS) and thermodynamic calculations. In the presence of water vapor, the formation of volatile Si(OH)(4) was responsible for the loss of mullite phase in the fiber of the ceramic-matrix composite (CMC). XPS analysis revealed the formation of surface aluminosilicates for the water-vapor-exposed CMC for 1000 h.