Ali, S. and Azzam, B., "Mechanical, Tribological Properties and Surface Characteristics of Developed Polymeric Materials Reinforced by CNTs," SAE Int. J. Fuels Lubr. 8(1):35-40, 2015, doi:10.4271/2015-01-0690.
The aim of this research is to assess and develop a polymeric material consisting of a mixture of high-density polyethylene (HDPE) and ultra- high- molecular- weight polyethylene (UHMWPE) reinforced by carbon-nanotube (CNT) by optimizing the mixing concentration of the three constituents. This optimized mixture is accomplished by using a melt extruder-mixing process. An experimental evaluation for accurate assessment of the developed nanocomposite material characteristics is achieved by using a universal tensile test machine and a plint-tribometer pin-on-disc machine. Moreover, the hardness of the material surface and its surface topography are assessed by a hardness tester machine and SEM technique, respectively. Developed samples for testing are classified into two groups of nanocomposites. The first group is created through mixing two pure polymeric UHMWPE and HDPE with different mass ratios of each. While, the other group is created through mixing three components UHMWPE, HDPE and CNTs with constant 50 wt.% of UHMWPE. Thereafter, CNTs with rations of 0.5, 1.0, 2.0, 3.0 and 4.0 wt.% to 49.5, 49.0, 48.0, 47.0 and 46.0 wt.% of HDPE to create different nanocomposite materials. The mechanical and tribological properties of this new developed material are obtained through testing of the two groups' samples to measure the tensile strength, friction coefficient, wear rate and surface hardness. Then, the best developed nanocomposite material is selected based on its mechanical and tribological properties. To ensure that the obtained nanomaterial has proper surface morphology, the SEM technique as a surface metrology tool is used to characterize the selected sample and to predict the CNTs dispersion homogeneity. The results show that the developed nanomaterial has achieved mechanical and tribological properties which outperform currently available materials with reasonable surface homogeneity.