Specific erosive wear rate of neat polymer films and various polymer composites

Abstract

The behavior of unidirectional carbon fiber-reinforced polyetheretherketone composites was studied under solid particle erosion, using different impact conditions and erodents. The data were analyzed on the basis of a newly defined specific erosive wear rate, allowing a better comparison of erosion data achieved under various testing conditions. Characteristic wear mechanisms of the carbon fiber/polyetheretherketone composites consisted of fiber fracture, matrix cutting and plastic matrix deformation, the relative contribution of which depended on the impingement angles and the carbon fiber orientation. The highest wear rates were measured for impingement angles between 45 and 60°. Another type of polymer composites, the so-called microfibrillar composites, which consisted of polyethyleneterephthalate fibrils in a high-density polyethylene matrix, exhibited a maximum erosion rate in the range of 30° to 45°, i.e. closer to that typical for the erosion of ductile polymers. The absolute values for the microfibrillar composites were, however, higher than those measured for the neat high-density polyethylene matrix. Using abrasion-resistant polymer films (in this case polyetheretherketone or thermoplastic polyurethane ones) on the surface of a harder substrate (e.g. a carbon fiber/polyetheretherketone composite plate) resulted in much lower specific erosive wear rates. The use of such polymeric films can be considered as a possible method to protect composite surfaces from damage caused by minor impacts and erosion. In fact, they are nowadays already successfully applied as protections for wind energy rotor blades.