Silicon carbide whiskers enhance mechanical and anti-wear properties of PA6 towards potential applications in aerospace and automobile fields

Abstract

The friction and thermal conductivity are two vital factors affecting braking components in manned aircraft. It is imperative to find a rational design basis for high-performance lightweight polymeric materials with excellent toughness, coefficient of friction, and thermal conductivity. In light of the outstanding mechanical strength, stiffness, and good dimensional stability of polyamide 6 (PA6), herein, we have demonstrated the fabrication of high-performance PA6 composites by adding one-dimensional SiC whiskers (SCWS) as both a reinforcement agent and anti-abrasion agent. The results show that addition of 2 wt% SiC whiskers (SCWS) increases the tensile strength of PA6 by 37.6% (reaching 58.2 MPa). Meanwhile, the elongation at break is over five times (around 280%) of that of the PA6 matrix, which means that the fracture toughness is increased around seven-fold. Moreover, the addition of 30 wt% SCWS reduces the coefficient of friction from 0.31 for the PA6 to 0.15, indicating improved anti-abrasion performance. Such significant improvements in both mechanical and anti-wear properties are primarily due to the high stiffness of SCWS and the strong interfacial interactions with the PA6 matrix. This work provides a facile approach to the design of mechanically robust, wear-resistant polymer composites which hold significant promise for producing advanced gears and bearing parts in aerospace and automobile applications.