Low Velocity Impact Fatigue Studies on Glass Epoxy Composite Laminates with Varied Material and Test Parameters - Effect of Incident Energy and Fibre Volume Fraction

摘要

An effort made to study the effects of fiber volume fraction and incident13; energy on the impact damage tolerance of composite laminates subjected to low13; velocity impacts at constant strike velocities. Repeated drop tests were conducted using an13; inhouse built drop weight impact-tester: Delamination-area was used as parameter for13; quantifying damage while the number of drops (impacts) to failure use to assess the13; damage tolerance limits. The delamination area was found to increase and then saturate13; after a certain number of drops. Impact fatigue studies showed the existence of a critical13; Incident energy (Ec) around which design of opmposite structures can be based. Also the13; minimum incident energy required to fracture the sample in a single impact (ESDT)was13; evaluated from the data. One of the interesting observations made was that for any given13; incident energy, the delamination area was found to be minimum at a certain fiber volume13; fraction (0.5 in this case) of the laminate. This was explained on lines of failure13; mechanisms reported earlier.13;