A Composite (Taguchi-Utility-RSM) Approach for Optimizing the Tribological Responses of Polytetrafluoroethylene (PTFE) Nanocomposites for Self-lubrication Applications

Abstract

A composite approach (Taguchi-Utility-RSM) is proposed to optimize the Tribological responses of Polytetrafluoroethylene (PTFE)/Halloysite nanotubes (HNTs) nanocomposite material for self-lubrication applications. These nanocomposites can be utilized as slide bearings for conveyors in paper, textile, and food industries. The main objective is to determine the optimum input parameters, those will give minimum wear rate, minimum coefficient of friction and maximum specific wear energy. Coefficient of friction (COF), specific wear rate (SWR), and specific wear energy (EW) are considered as responses. Effect of input parameters such as composition (wt.% HNT addition), load, sliding speed and sliding distance on the output responses are studied. As per Taguchi orthogonal array of L27, experiments have been conducted on the PTFE/HNT nanocomposites on Pin on Disk apparatus. The weights values are calculated based on designer’s choice and utility index values for all experimental runs are evaluated. Later, by using response surface methodology the utility index values are optimized for maximum utilization. The response values are measured and calculated. Taguchi method is used and SN ratio for main effects is plotted. Single response optimization is carried out corresponding to optimum values of COF (C2L1D1S1), SWR (C1L1D2S2), and EW (C1L1D3S2). Utility method is followed and utility index values for each run are calculated. Surface plots are plotted and found the interaction effect of input factors on the utility index. In optimization, 4% of composition, 8.5354 N of load, 2 km of distance and speed of 1 m/s are found to be optimum for maximum utility index of 15.5032 with desirability value of 1 and is observed within 95% confidence interval.