On the interfacial properties of CCF300/QY8911 composite with cyclical hygrothermal treatments

The specimens of CCF300/QY8911 composite are treated with cyclical moisture absorption-desorption processes. The curves of moisture absorption and desorption are drawn and are fitted in the Fick Second Law. Interfacial properties are characterized with the method of the interlaminar shear strength (ILSS), and cross-section and lateral morphologies are observed by SEM. The results indicate that the behaviors of moisture absorption and desorption of specimens are in accordance with Fick Second Law, with the moisture immersion for 14d at 71°C, the samples obtain the saturated moisture absorption contents; Absorption moisture has reversible and irreversible destructive effect on of CCF300/QY8911 composite. Reversible damage on fiber/resin interfaces can be eliminated after desorption processing, which increases the dry ILSS; the increase of hygrothermal cycles can lead to further irreversible damage on the fiber/resin interfaces and make the ILSS of CCF300/QY8911 composite decrease. However, the absorption moisture is the key factor which causes the degradation of ILSS performance.