Pengaruh Kelembaban Adherend Pada Durabilitas Perbaikan Komposit

Abstract

In this paper, the effect of moisture on the durability of composite repair is investigated using fracture mechanics approach. The specimens of double cantilever beam were made from two composites adherend (fiberglass/unsaturated polyester) bonded by epoxy adhesives. The adherend were immersed in the distillate water to gain moisture and then dried in different drying conditions at room temperature (RT) for 12 hours followed by 100 oC for 15 minutes, 50 oC for 5 hours and 100 oC for 2.5 hours. The spesimen was wedged tested in both dry and wet condition in room temperature. The results show that the lower moisture about 2.8%wt according to drying temperature 100 oC give the better durability followed by drying temperature of 50 oC and room temperature. The indication is shown by stable crack growth at higher fracture energy and also by low crack speed at higher fracture energy. Whereas, for wet testing, the better result is reached by drying temperature of 50 oC (moisture contents of 4,4 %wt) and for dry temperature of 100 oC give the worst result. The contradiction suggested that drying temperature for adherend of composite repair should not higher than 100 oC