Evaluation And Analysis Of The Low-velocity Impact Resistance Of Glass Fiber Reinforced Aluminium Laminates

Glass Fiber Reinforced Aluminum Laminates(GLARE) consists of high strength Aluminum alloy sheet and Glass Fiber/Epoxy resin prepreg alternately, and it is solidified by using Autoclave under specific temperature and pressure. GLARE laminates integrates the advantages of Aluminum alloy sheet and Glass Fiber/Epoxy resin prepreg. Compared with Aluminum alloy sheet, GLARE laminates has better corrosion resistance, fire resistance, lower density, and higher damage tolerance,especially in terms of impact and fatigue performance. Compared with Glass Fiber/Epoxy resin prepreg, GLARE laminates has more advantages in processing and cutting. Although its manufacturing cost and complexity are higher than those of Aluminum alloy sheet, it is more convenient to perform the damage inspection and maintenance due to its longer service of GLARE laminates as aircraft structural materials. Because of these excellent mechanical properties, GLARE laminates is widely used in aerospace and other fields. In this dissertation, an impact test with low velocity on GLARE laminates was simulated by using the ABAQUS/Explicit Solver to study the dynamic response during the impact process.Different impact energy, different punch diameter and different hammer weight were used in an impact test with low velocity on GLARE laminates. The results show that in the same kind of test condition, with the increase of the impact energy,the response time of low velocity impact action of GLARE laminates shortens gradually, and as the peak load and deflection increasing, the effect of punch diameter and hammer weight increasing on the bearing capacity gradually decreases.The finite element model of GLARE laminates subjected to low-velocity impact action was established by using the Software ABAQUS, and the reliability of finite element model was verified by comparing the test results with numerical simulation.The finite element analysis of the impact resistance of GLARE laminates with a hole based on the above finite element model may serve as a prediction study. In order to investigate the influence law of distance L(L indicates the distance fromimpact center to the edge of hole) and the hole diameter D on the impact resistance of GLARE laminates, we respectively analyzed the crack length of specimen, the time of initially damage and peak load. The numerical simulation results show that when GLARE laminates subjected by impact loading, the aluminum alloy sheet of non-impacted side always occurs initial damage and crack earlier compared with impacted side, and damage area of non-impacted side is bigger. The empirical formula was obtained to describe the relationship between crack length and the L.When the impact energy is 40 J and the diameter is 8mm, it can be used to predict the crack length of horizontal and vertical of impacted side and non-impacted side. And it is predicted that reducing the diameter of the hole appropriately will increase the impact resistance of GLARE laminates effectively.