Tribological Response of Polyamide 66 and Polytetrafluroethylene (PA66/PTFE) Blends in Two Body Abrasion Through Multipass Condition

Abstract

The different weight percentages of 95/5, 90/10, 85/15, 80/20, 75/25 and 70/30 of PA66/PTFE blend composition was investigated as per the ASTM G99 method. The abrasive wear studies were conducted in multipass condition against waterproof silicon carbide (SiC) abrasive paper of 180 and 320 grit at a constant load of 5 N and 10 N with a sliding velocity of 1 m/s for varying abrading distances using pin-on-disc machine. It was found that the wear volume loss of composites increases linearly with increase in applied load and abrading distance. A significant reduction in wear resistance has been observed in terms of wear volume and specific wear rate with increase in addition of PTFE dosage in PA66/PTFE blend. Further, it was observed that the wear volume loss of composites has been decreased with increase in the rank of grit size. Higher wear volumes was due to deep penetration of large sized particles of 180 grit abrasives and less for 320 grit abrasives due to the transition of abrasion wear to sliding. The specific wear rate decreases with an increase in abrading distance for all the tested specimens. Microcutting, microploughing and fatigue loading of abrasive particles are the major failure mechanisms observed during the worn surface analysis using SEM.