Tribological and mechanical characterization of glass fiber polyamide composites under hydrothermal aging

Abstract

Polymer composites are increasingly used in applications where they are subjected to abrasive wear. The bulk of prior research has focused on the performance of polymers under sliding wear conditions and in some cases resulted in a contradiction, particularly when it comes to the effect of reinforcing fibers on the wear performance. Another omission is the absence of pre-conditioning or accelerated aging which is clearly an important factor from an application standpoint. This work aims to highlight the influence of hydrothermal aging on the tribological and mechanical performance of polyamide 6 (PA6) and glass fiber-reinforced polyamide 6 (PA6-GF). The friction and abrasion wear behavior of unconditioned and conditioned PA6 and PA6-GF composites are measured against silicon carbide grinding paper on a pin-on-disk tribometer in a demineralized water medium at 60 °C. Specimens are conditioned in demineralized water at room temperature (RT) 25, 40, and 60 °C to investigate the effects of moisture and temperature. The presence of up to 25 wt.% glass fiber (GF) in PA6-based composites exhibits an increasing trend in abrasion wear mass loss and a reduction in coefficient of friction (COF). Interestingly, the mass loss of specimens conditioned to saturation does not increase compared to that of unconditioned samples. The FTIR spectroscopy is used to study the polymer degradation during hydrothermal aging.