The effect of environmental conditions on adhesive connection composite plates

In this study, the effect of environmental conditions on bonded composite sheets was investigated experimentally. The effect of hot water was investigated on four different sample geometries, which were prepared in connection with bonding, with single effect overlap connection, single effect patched connection, double effect patched connection and sheets. In the study, two different types of glass fiber reinforced epoxy composite sheets were used in each geometry, including fiber reinforcement angle (woven) [00]8 and [450/-450/00/900]s. For the single-effect thrust joint, the thrust length was determined as 25 mm and 35 mm for the composite samples with both orientations. In the patch orientation used in the single and double acting patched connections, the samples with the same and different orientation with the plate were used in the patch orientation. The plates are considered as 25 mm and 30 mm in both orientations. All samples were kept in water with a temperature of 40 0C, 60 0C and 80 0C for 15 days, 30 days and 45 days. At the end of the period, the absorption rates of the samples were determined and compared between each other. At the same time, the maximum damage loads of the samples subjected to tensile test were determined and compared. In the experimental study; damage load values obtained from glass fiber reinforced epoxy composite samples with fiber reinforcement angle [00]8 were found to be higher than glass fiber reinforced epoxy composite samples with fiber reinforcement angle [450/-450/00/900]s. As a result of the tensile test, it was determined that the maximum damage load value obtained from the dry samples was higher than the damage load values obtained from the samples kept in the hot water. It was determined that the highest moisture absorption rate and the lowest damage load values of the samples were obtained when it was kept in 80 0C hot water for 45 days. In this sense, it was determined that the absorption rate of the samples increased when the waiting time and degree of hot water increased, but the maximum damage load values decreased depending on the temperature level.