Fatigue performance studies on fiber reinforced composites

• Main Author: Phua, Nicholas Jia Fu
• Other Authors: Sunil Chandrakant Joshi
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/168593
• Institution: Nanyang Technological University

In a variety of engineering and mechanical research domains, composite materials have become a viable alternative to traditional materials. Composites, particularly fiber reinforced polymer composites, have proven to be an excellent substitute for conventional metals. Fatigue test is one of the fundamental tests that composite materials must undergo. It consists of evaluating cyclic behavior in materials. During fatigue testing, materials are loaded until failure or until a percentage of the total stiffness loss, as determined by the researcher. Metals and composite materials behave differently under fatigue loading. Failure in metals starts with initiation of a single fracture and subsequently the crack's spread. Contrarily, it is a difficult process for composite materials since they have qualities that prevent cracks from forming. The fatigue behavior of CF-PA6 composite is highlighted in this review study. Fiber material, matrix material, as well as the damage development process at the microscopic level, are variables that lead to such behavior in composite materials. The stress ratio, mean stress, loading condition and testing frequency are all included in the loading condition parameters. In tensile testing, the ultimate tensile strength was found to be 53.6855 kN. On the other hand, the endurance limit was found at 50% of ultimate tensile strength in fatigue testing and the samples fatigue mechanism was verified using microscopy. They exhibited progressive fiber breakage, matrix crack, and debonding, resulting in more extensive and distributed damage. Possible future works would be to study the effect of fillers on fatigue behavior of CF-PA6 composites.