Interfacial properties and high-temperature mechanical behavior of fiber-reinforced ceramic composites

Abstract

Abstract Mechanical properties of ceramic composites reinforced with continuous fibers have been extensively studied in recent years. Most of these studies have been performed to characterize, both analytically and experimentally, the mechanical response of composites at relatively low temperatures where the constituents of the composite behave in a brittle manner. These studies have shown that ceramic composites with carefully tailored fiber-matrix interfacial properties can be created to display impressive strength and toughness. However, a similar understanding of the mechanical response of these composites at elevated temperatures is lacking at the present time. An initial attempt is made in this paper to describe mechanical properties of ceramic composites at elevated temperatures. For the sake of brevity only short-term mechanical properties are considered, and time-dependent mechanical behavior such as creep and fatigue is not considered. These results are illustrated using a model composite materials system comprising a zircon matrix uniaxially reinforced with silicon carbide fibers. Constituent properties of the fiber, matrix, and fiber-matrix interface are considered in describing the overall mechanical response of these composites at elevated temperatures. General remarks on the mechanical behavior of composites at elevated temperatures and the role of interfacial properties are made based on results of this study. In addition, an attempt is made to identify research needs for the future.