The Effect of Thermal Aging to The Impact Properties of Glasss Fiber Reinforced Epoxy

Fiber reinforced composite materials are widely used in automotive industries and aviations due to their special characteristics such as high strength to weight ratio. As the fiber reinforced composites are used as structural materials, they are sometimes used in more complex environments such as in high temperature application. Under thermal aging condition, thermal stresses may develop in composite laminates due to the difference in the coefficient of thermal expansion of the fibers and the matrix. This environment is known to cause degradation of composite materials. For this reason, an experiment is done to investigate the effect of thermal aging to the impact characteristics of the structures. In this study, two different types of glass fiber reinforced epoxy with varied fiber orientation are studied after being impacted by a standard drop weight with 10-J impact energy. Thermal aging is performed by exposing the sample to the temperature of 1000C for 50 hours. The damage zone are studied by using ultrasonic non-destructive inspection. The impact resistance of both form of fibers are declined when subjected to thermal aging. The damage area produced is larger and it shows that extreme temperature greatly affect the structural intergrity of the structures. Thick woven glass reinforced composite shows the best structural behavior with minimal damage area. Thin chopped glass fiber reinforced composite has the lowest impact resistance among the others which produce the largest damage area. The test revealed the woven glass fiber are more ductile than the chopped glass fiber.