Frequency Effects on Fatigue Behavior of a Silicon Carbide Fiber‐Reinforced Glass–Ceramic Composite (SiC/MAS)

Abstract

The effects of cyclic frequency on the fatigue behavior of silicon carbide (Nicalon) fiber‐reinforced glass–ceramic matrix (SiC/magnesium aluminosilicate (MAS)) were investigated. Tension–tension fatigue tests were conducted at two frequencies, 10 and 900 Hz, to establish stress versus cycles to failure (S–N) relationships. Cycles to failure at a given stress level decreased with an increase of the applied frequency. Analysis of damage mechanisms suggests that there was an enhancement of fiber/matrix interfacial bonding at the higher frequency due to the formation of SiO2 from the reaction of oxygen species of the matrix with SiC of the fiber.