2018-04-162018-04-162018-02-28http://hdl.handle.net/20.500.12688/8650Στην παρούσα εργασία μελετάται η αντοχή ενός σύνθετου υλικού, εποξικής ρητίνης ινοπλισμένο με υαλοϋφασμα, σε δοκιμασίες κάμψης τριών σημείων και εφελκυσμού. Οι δοκιμές πραγματοποιήθηκαν σε δοκίμια με διαφορετικές γωνίες προσανατολισμού των ινών του υαλοϋφάσματος σε σχέση με τον άξονα πραγματοποίησης των δοκιμών.Fiber reinforced composites are gaining ground in the market day by day, because of their excellent properties that present. For example, composites can achieve great mechanical strength while being lightweight. In the present thesis is studied the flexural strength of glass fiber reinforcement epoxy composites. More specific the tests have been done with different orientation of the fibers. The results have shown that the composite with fiber orientation of 0o has the best properties, like flexural strength, elasticity and tensile strength. The composite consists of 9 layers of fiberglass (interglass) 60*45, 3.3 mm width and 290gr/m2. The layers are bonded together with Epoxy Resin LF.After the manufacturing progress the plates stayed in a dry place to mature the bonds between the fiberglass and the epoxy. Then the plates designed properly with the test objects in the right cutting angle (00,300,450,600). After this the plates were cut into a cutting wheel to acquire the right dimensions. The study of the results shows that are consistent with analogous results in the literature. Epoxy laminates reinforced with glass fibres parallel in one direction (GFR) shows to have in the 0o direction maximum strength and this decreases to 0° and then the phenomenon is reversed. This phenomenon is explained as follows: the gradual change of the orientation angle of the fibers changes the contribution of the matrix to mechanical strength. In our case, there was reinforcing for bothdirections 0o and 90o, so the contribution of the matrix seems to play an important role, but the behavior of the material is more complicated. According to results the strength- cutting angle orientation of the specimens, the tensile and the flexural strength of the composite have the maximum value at the angle 0o. For all other angles, these strengths are reduced as shown in the relevant diagrams. An analogous picture also shows the elasticity results. The maximum modulus of elasticity for tensile and flexural test was at 0 ° and for all other angles there was a decrease in the modulus of elasticity. The flexural and tensile results are consistent and comparable with the results of compression in the same specimens according to a thesis carried at the Material Technology Laboratory. In chapter 6, the results of our test are shown in detail with diagrams and tables for each angle.Attribution-NonCommercial-NoDerivs 3.0 United StatesΜελέτη αντοχής σε εφελκυσμό και κάμψη σύνθετου πολυμερούς (Εποξυρητίνης ενισχυμένης με υαλοΰφασμα).A study of tensile and flexural strength of glass fiber (Reinforcement epoxy composites).