Polyetherimide composites with gamma irradiated carbon fabric: Studies on abrasive wear

Interfacial adhesion between matrix and fiber is an important aspect in controlling performance properties of the composites. Carbon fibers are known for chemical inertness and hence limited wettability with the matrix and need prior surface treatment to improve its adhesion with the matrix. In this work, γ (gamma) irradiation technique with varying doses (0–300 kGy) was employed to the twill weave carbon fabric (CF) to develop composites with polyetherimide (PEI) matrix based on impregnation method followed by compression molding. Composites were characterized for interlaminar shear strength (ILSS) and abrasive wear performance. Improvement in the friction and wear properties was correlated with the improvement in ILSS as a result of CF treatment. Higher the treatment dose, higher was the ILSS and better was the tribo-performance. SEM studies on fibers indicated increased roughness of the surface as a consequence of treatment and dose. Fourier Transform Infrared Spectroscopy in Attenuated Total Reflectance (FTIR-ATR) mode indicated inclusion of functional groups (mainly carbonyl). Both these factors were responsible for enhancing the fiber–matrix interface. Various techniques such as adhesion test, fiber tension test and Raman spectroscopic analysis of CF were also exploited to analyze the influence of γ irradiation on CF.

Research highlights
► γ-treatment of carbon fabric led to significant changes in surface topography.
► With increase in dose from 0–300 kGy, roughness of the fiber surface increased.
► Tensile strength of the fiber decreased with increase in irradiation dose.
► Improvement in ILSS of composites was observed due to improved adhesion.
► γ-treatment proved beneficial for abrasive wear performance of composites.