Effect of Thermal Ageing on the Mechanical Strength of Carbon Fibre Reinforced Epoxy Composites

Polymers

Maria Pia Falaschetti¹  Francesco Rondina¹  Lorenzo Donati¹  Nicola Zavatta¹ 

[1] Department of Industrial Engineering DIN, University of Bologna, Via Fontanelle 40, 47121 Forlì, Italy;

关键词: thermo-oxidative;    temperature;    mechanical properties;    carbon fabric;    CFRP;    thermoset;   

DOI  :  10.3390/polym13122006

来源: DOAJ

【 摘 要 】

Applications of Carbon Fibre Reinforced Polymers (CFRP) at temperatures over 150–200 °C are becoming common in aerospace and automotive applications. Exposure of CFRP to these temperatures can lead to permanent changes in their mechanical properties. In this work, we investigated the effect of thermal ageing in air on the strength of carbon fabric/epoxy composites. To this end, accelerated artificial ageing at different temperatures was performed on carbon fabric/epoxy specimens. The flexural and interlaminar shear strengths of the aged specimens were assessed by three-point bending and short beam shear tests, respectively, and compared to those of unaged samples. For ageing at temperatures below the glass transition temperature of the resin, $T_g$, a moderate reduction of strength was found, with a maximum decrease of 25% for 2160 h at 75% $T_g$. On the other hand, a rapid strength decrease was observed for ageing temperatures above $T_g$. This was attributed to degradation of the epoxy matrix and of the fibre/epoxy interface. In particular, a 30% strength decrease was found for less than 6 h at 145% $T_g$. Therefore, it was concluded that even a short exposure to operating temperatures above $T_g$ could substantially impair the load-carrying capability of CFRP components.

【 授权许可】

Unknown