DYNAMIC MECHANICAL CHARACTERIZATION OF CF/GF HYBRID REINFORCED POLYMERIC COMPOSITE STRUCTURES

The importance of dynamic mechanical analysis (DMA) as a research tool in the study of polymeric composite structures behavior has been already demonstrated in the literature. Many papers were approaching the relaxation phenomenon within the polymer based composite structures and thereby their behavior under various conditions of stress and temperature. Supplementary, the effect of fillers geometry, orientation and volume fraction have been extensively approached while considering the micromechanical level and their role in the mechanical properties were suitable stated. Hybridization of two different fillers has proven to an effective method in material design allowing their developers to tailor their properties according to the application driven imposed requirements. The herein paper attempts to present a comparative study centered on the development and characterization of a hybrid polymeric composite structures made up from different combinations of carbon and glass fibers by evaluating their dynamic mechanical properties. The samples were measured using the Dynamic Mechanical Analyzer (DMA) from NETZSCH-DMA 242 C, in the 3-point bending mode, nitrogen atmosphere, at a scanning rate of 3 K/min from -40 to 180(0) C with a fixed frequency of 1 Hz. Storage and loss modulus, loss tangent were recorded as function of temperature both on longitudinal and transverse direction of the unidirectional carbon fibers, in two consecutive heating cycles. A reference sample was set up to aid the comparison analysis, made entire from one filler type. The effect of the fillers type, fillers relative volume fraction and temperature on the storage and loss moduli will be deeply investigated.