Elastic recovery at graphene reinforced PA 6 nanocomposites

In this study tensile-mechanical properties of graphene containing polyamide 6 nanocomposites were deeply analysed via cyclic measurements. Injection moulded specimens with different nanofiller contents (0…1 wt%) were used for the investigations. At the cyclic tests the loading force was increased with 100 N increments in each cycle and the relaxation time was set to be 30 s. After the relaxation time the residual strain was determined in each cycle (plastic deformation). The results showed that the presence of graphene reduced the plastic deformations (i.e. elastic recovery was enhanced compared to the matrix). It results in that the creeping behaviour of nanocomposites becomes considerable just at higher loads. Based on the results it can be stated that the pure linear elastic region of the tensile curves became wider by the incorporation of graphene nanoparticles into polyamide 6 matrix, meaning that the utilization range is also wider regarding the mechanical stresses