Mathematical modeling of mechanical properties of PA6/NBR/Clay Nanocomposites Fabrication using the Thermal Friction Stirs Processing

Two phases nanocomposite based polyamide 6/nitrile butadiene rubber reinforced by nano clay has gained wide application in various industries. Since friction stir processing is one of the fabricating methods for nanocomposites, in this paper, the response surface methodology (RSM) was used to investigate the effect of rotational speed, traverse speed and shoulder temperature on the tensile and impact strength. At first, a number of trail runs were performed in order to determine the limits of the process parameters. Analysis of variance was used to investigate the process parameters and mathematical models. Comparison of the results of these methods with experimental results indicated that RSM results had a lower percentage of error. Using a mathematical model, the effect of the mentioned parameters on tensile and impact strength was investigated to obtain optimum conditions. Results indicated that with an increase in rotational speed tensile strength and impact strength increased. With increase in traverse speed, tensile strength and impact strength decreased. Simultaneous optimization of the input parameters for maximization of the output responses led to a tensile strength of 31.3MPa and impact strength of 70.3 j/m was achieved at the rotational speed of 1200 rpm, traverse speed of 20 mm/min and shoulder temperature of 125 °C.