Effect of nano Al2O3 fillers and cross head velocity on interlaminar shear strength of glass fiber reinforced polymer composite

The present investigation emphasizes on the effect of nano Al2O3 filler and cross head velocity on mechanical properties of glass fiber reinforced polymer composite (GFRP). Nano Al2O3 filler of 3 wt% of epoxy is dispersed into the epoxy matrix through temperature assisted magnetic stirring followed by sonication for a time period of 60 min. GFRP composites are fabricated by hand-lay-up techniques. It is observed that flexural strength about 14 % and interlaminar shear strength (ILSS) about 11 % improved in nano Al2O3 filled GFRP composite as compared to control GF composites. Further, ILSS is evaluated as a function of volume fraction of glass fiber and at different cross head velocity (1, 50, 100, 500 and 1000 mm/min). The results revealed that ILSS values increases with cross head velocity from 1 to 100 mm/min and decreases further increase in cross head velocity. This may be attributed to at higher cross head velocity (up to 100 mm/min), micro cracks propagate through fiber/matrix interface rather than the weakest epoxy matrix and breaks the strong fiber during crack propagation resulting increase in ILSS. Addition of 3 wt% of nano Al2O3 does not have influences on glass transition temperature. Scanning electron microscopy images of ILSS fractured surface features are analysed to understand the failure mode of glass fiber reinforced polymer nano composites.