Investigation of mechanical and tribological properties of carbon nanotube filled polyamide 6 polymer nanocomposites

In this study, 0,1; 0,2 and 0,3 wt.% multi-walled carbon nanotube (MWCNT) filled polyamide 6 (PA6) polymers were produced by extrusion and injection molding methods. In order to determine mechanical properties such as tensile test, impact test and bending tests, and physical properties such as density and X-ray diffraction (XRD) tests were applied to PA6 polymer and PA6 nanocomposites. Also, for the thermal properties, differential scanning calorimeter (DSC), thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA) methods were applied. Wear and friction tests were carried out at the sliding speeds of 0,4-1,6 m/s, applied loads of 10-40 N and under dry conditions by using pin-on-disc system. As a result of studies, it was determined that the tensile strength, the modülus of elasticity, the bending strength and bending modülus decreased with addition of 0.1wt.%MWCNT while the properties increased with increase of the MWCNTs content. The glass transition temperature (Tg), the crystallization rate (% Xc), the storage modüle (E') and the loss modülus (E'') were increased with MWCNTs content. According to the results of XRD, strong γ-form was formed in PA6 polymer while α-form was formed in the MWCNT filled PA6 polymers. Coefficient of friction and wear rate of PA6 polymer and PA6 nanocomposites increases with increase both applied load and sliding speed. The coefficient of friction and wear rate of the PA6 polymer decreased significantly with the addition of MWCNTs. The lowest coefficient of friction and the wear rate were obtained in 0,3 wt% MWCNT filled PA6 nanocomposites.