A Fuzzy Logic Approach for Predicting Effect of Thermal Aging on Surface Hardness of Carbon Fiber Reinforced Composites

In the present work, a fuzzy logic approach was used in order to determine the effect of thermal aging on the surface hardness of phenolic resin reinforced by woven carbon fibers (CFP). For this purpose, the specimens made from CFP composites with different fiber volume fraction (20%, 30%, 40%, and 50%) were exposed to different thermal aging fashions (refrigerated at -30 ºC, room temperature at 25 ºC, and thermally aged at 50 ºC).The surface hardness values of both the pristine and aged specimens were then experimentally determined using Barcol hardness testing machine. The hardness values for CFP composites were also predicted by two types of fuzzy inference systems (FIS), i.e. Mamdani and Sugeno methods. Results of the developed fuzzy logic models were compared with the experimental results and it was found that the Sugeno method performed better than Mamdani method.