Fuat OKUMUÅž
Gediz University, Turkey
Title: Experimental fatigue analysis and investigation of optimal- angle ply orientation of composite tubes under variable cyclic loading
Biography
Biography: Fuat OKUMUÅž
Abstract
In this study, optimal angle-ply orientation of symmetric composite tubes under fatigue loading is investigated. 60The fiber-reinforced plastic tubes were manufactured from S-glass/polyester. The layers were manufactured symmetrically in [750]2, [600]2, [500]2, and [450]2 orientations. Burst pressure of filament-wound composite tubes under alternating pure internal pressure was measured experimentally. Internal fatigue pressure testing method was applied to the composite tubes in close-ended condition. For this study, a programmable logic controlled (PLC) hydraulic pressure testing machine has been employed. The static burst pressure values of specimens were measured; subsequently, fatigue test pressure was applied in 75, 60, and 50 % stress levels of burst pressure for each orientation. Damage propagations of the composite tubes on these stress levels were observed as whitening ,leakage, and final failure for [600]2, [450]2, and orientations. When the damage propagation of [750]2 angle-ply tubes was observed, whitening and leakage did not occur and final failure occurred suddenly. Stress-cycle curves obtained from the tests are given in graphics. Experimental results reveal that variation in stress levels and the winding angles have considerable effects on final failure cycles, which is also presented graphically.