Kompozit malzemelerde yapışma bağlantılarının mukavemeti üzerine yama fiber takviye açısı etkisi

In this study, the patch fiber reinforced angle effect on the strength of adhesively bonded composite was investigated experimentally. [θo]8 layered composite plates which were woven glass fiber reinforced and epoxy resin matrix, were adhered by epoxy based adhesive. The experimental study was realized as static tensile test. The fiber reinforced angle of patch, patch length and adhesive thickness were used as a parameter. With the developing technology of composite materials, land, air and sea vehicles often become the material of choice. This vehicles, light weight, sturdiness, easy to be repaired some requirements such as low heat conduction ability and have come to the fore. The adhesively bonding methods are widely used for connecting of composite plates. This joint type was preferred as it was not have extra weight and it was not effect of vibration. In the literature, stress analysis of single and double joints, joint geometry effect on the strength of joint, failure analysis of adhesively joints, reinforcing of adhesive effect on the joint strength and temperature and pressure effect on the joint strength were researched. In the studies, the mechanical properties of adhesive, lap length, adhesive thickness and the other geometrical changing were used as parameters. In this study, composite plate thickness (thc= 1.25 mm), composite plate width (w= 30 mm) and composite plate length (L = 100 mm) were used as fixed parameters. Also, lap length (Lap) and adhesive thickness (tha) were changed 25.4, 38.1, 50.8 mm and 0.2, 0.6, 1.0 mm, respectively. The fiber reinforced angle of composite plate was 0o and the fiber reinforced angles of patch were varied 0o, 15o, 30o and 45o. The composite plates were supplied from Izoreel Firm™ with fixed thickness and fixed width. These plates were cut by milling machine and later bond areas were abraded with 40 grid sand paper. The bond surfaces were free from surface roughness and acetone then with the help of a cotton cloth was cleaned. The bonding processes were realized in the special moulds. The bonded specimens were stayed in room temperature about 15 days for curing. Then the static tensile load were applied the specimens and the load-extension data were recorded. The static tensile tests were realized in 100 kN capacity Instron BS 8801 static tensile testing machine with 0.5 mm/min cross head speed. For reliability of experimental study, three samples were produced for every parameter and the experiments were realized. The failure loads were calculated from arithmetic average of failure loads of three samples. TYB are called samples which are bonded to one side, while double side bonded to ÇYB samples. The obtained results were presented as graphs. The failure loads were increased from 10% to 45% with increasing of Lap length for all patch fiber reinforced angle of TYB type joints. In the TYB type joint, the maximum failure load was determined as 5430 N for Lap = 50.8 mm and patch reinforced angle of 15o and the minimum failure load was determined as 3121 N for Lap = 25.4 mm and patch reinforced angle of 0o. When the results are evaluated for the patch reinforced angle, the biggest failure loads were determined for patch reinforced angle of 15o and the lowest failure loads were determined for patch reinforced angle of 0o. When the TYB and ÇYB type joints compared with each other, it was determined that, the failure loads was increased from 73% to 160% varying rates. In the ÇYB type joint, the maximum failure load was determined as 8605 N for patch reinforced angle of 15o and the minimum failure load was determined as 6127 N for 45o. When the thickness of adhesive was increased, the failure loads were decreased from 11% to 30% varying rates.