Evaluating the Mechanical Properties of Carbon Fiber Reinforced Polymer Matrix Composite Materials at Room and Elevated Temperatures

Abstract

A series of tensile, compression and shear tests in room temperature were carried out on carbon fiber reinforced polymer matrix composite materials (IM7/PEEKEK) to evaluate their mechanical properties. Also tensile tests at 160 degrees Fahrenheit (72 degrees Celsius) in longitudinal and transverse directions were done to study the effects of such temperature on the tensile strength of the mentioned composite materials. The setup of the testing equipment and the furnace that was used to provide elevated temperature conditions limited the possibility of conducting compressive and shear tests at high temperature as well as raising the temperature to higher levels. The experiments were set up in accordance with ASTM standards that best corresponded to the test specifications. Specimens were categorized into groups according to their nature of testing. All the specimens were reinforced at both ends by means of tabs which were bonded on both faces to reduce the effects of the external pressure exerted on them through the grips of the testing machines and were tested until failure. Load, elongation (displacement) and strain data were recorded by means of strain gages and data acquisition systems. The accuracy of the experimental data for the room temperature portion of the experiments is verified by comparing them to those of the most equivalent composite family, as having not been given any information regarding the structural properties and manufacturing processes of the composite materials that were used throughout the experiments made it difficult to find exact ASTM standards and reference materials for the testing and comparison of results. The results of the experiments showed that the tensile strength of this particular composite material is not effected by the 160 degrees Fahrenheit temperature; a point that is proved by the literature indicating their specific and sensitive application in aircraft heat dissipation [1].