Investigation of Fracture Prevention Effects of Composite Patches Repair on Cracked Al-Plates: Experimental and Numerical study

Today’s cutting-edge world of science and technology calls for composite materials to be widely employed in numerous industries, including marine, aeronautical and automotive due to their excellent mechanical, chemical and thermal characteristics. In various engineering applications composite materials are cost-effective, reliable, life saver and efficient. By reducing the strength-to-weight ratio by significant amounts, composite materials have revolutionized the manufacturing process of aircrafts. In the present research, 50 rectangular cracked aluminum alloy 7075 specimens with central crack were repaired by glass-epoxy composite patches with 0,90 and-45,+45 fibers orientations. Then, the specimens were subjected to uniaxial tensile loading test experimentally using the 600KN Santam testing machine. Next, the force-displacement curve for each repaired sample was monitored and plotted by the testing machine user’s software. After that, Abaqus as a finite element software was employed to numerically simulate and perform the tensile test with XFEM method on developed three-dimensional models. Lastly, the experimental and numerical results were validated and compared precisely. It was concluded that XFEM as an effective technique is capable of predicting crack propagation with maximum 0.0266 error percentage. Moreover, specimens repaired by glass-epoxy with 0,90 fibers orientation have the optimum performance while the ones whose fibers orientation is -45,+45 extended more before failure.