Wear 270 (2011) 146–151 Contents lists available at ScienceDirect Wear journal homepage: www.elsevier.com/locate/wear Experimental investigation of polymer matrix reinforced composite erosion characteristics G. Drensky, A. Hamed ∗ , W. Tabakoff, J. Abot Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, OH, USA article info Article history: Received 27 November 2009 Received in revised form 27 April 2010 Accepted 19 August 2010 Available online 3 December 2010 Keywords: Polymer matrix Composite Erosion abstract Solid particle erosion of a composite material of polyetheretherketone (PEEK) matrix and unidirectional (AS4) carbon fiber was investigated experimentally. Erosion tests were conducted with 10 m Arizona road dust and 100 m sieved runway sand particles in especially designed erosion tunnel at temperature up to 260 ◦ C (500 ◦ F) and impact velocities up to 152.4 m/s (500 ft/s). Experimental results are presented for the measured erosion rates of the unidirectional (UD) composite material at two perpendicular fiber alignment settings relative to the impacting particle stream. The results indicate a quasi-ductile behavior with peek erosion rate at 45 ◦ impact angle. Overall the erosion rate was found to increase with impact velocity. The sieved runway sand caused more than double the erosion of the Arizona road dust under the same impact conditions. The erosion rate was also found to increase with temperature except at normal impact. The fiber alignment orientation relative to the impacting particle stream influenced the erosion rate of the (UD) composite material. Higher erosion rates were measured at 90 ◦ fiber orientation than at 0 ◦ at ambient test temperatures as reported in prior investigations. However, lower erosion rates were measured at 90 ◦ fiber orientation than at 0 ◦ for the erosion at 260 ◦ C. Scanning electron micrographs (SEM) of post-erosion surfaces are presented. © 2010 Published by Elsevier B.V. 1. Introduction Traditional metal alloys are being replaced by lighter compos- ite materials that offer weight saving and strength improvements in propulsion systems [1]. In particular, the introduction of com- posite fan blades is one of the revolutionary advances in modern high by-pass turbofan engines. There is a need, however, to expand our knowledge of the behavior of aging components made of composite materials. The prognosis and life management of air- breathing propulsion systems requires characterization of foreign object damage and erosion of blade and coating materials [2,3]. However, solid particle erosion of composite materials has not been investigated to the same extent as metal alloys and ceramics. The presence of solid suspended particles in turbofan and gas turbine engine flow fields can have serious consequences on engine performance and life [2,3]. Particle impacts can reduce blade chord, increase surface roughness, and change the leading trailing and edge shapes of the blades in the compression system [4,5]. Ingested particles could impair thermal protection in the hot section through film cooling passage blockage and thermal barrier coating erosion [6]. Characterizing blade surface material erosion resistance under a wide range of particle impact conditions is critical to mitigate the ∗ Corresponding author. Tel.: +1 513 556 3553; fax: +1 513 556 5038. E-mail address: a.hamed@uc.edu (A. Hamed). consequences of these changes. This requires special erosion facil- ities that can simulate the aero-thermal conditions encountered in turbomachines [7]. Experimental based correlations for particle restitution and surface erosion by impacts are also needed, in com- bination with blade surface impact statistic from turbomachinery multi-phase flow numerical simulations, to predict the intensity and pattern of blade erosion [8]. It is well known that the erosion resistance of metal alloys and ceramic materials by solid particles depends on the impact velocity, impingement angle, target and erosive particle materials, particle size and shape, and that it is strongly influenced by temperature. The mechanisms of material removal by erosion include crack for- mation and fracture in brittle materials, and cutting and chipping in ductile materials. Consequently, the effect of impingement angle on the erosion rate differs significantly in ductile and brittle materi- als. Peak erosion of brittle materials occurs at normal impact while that of ductile material occurs at glancing impingement angles between 20 ◦ and 30 ◦ . Composite materials generally consist of two or more phases and their erosion mechanisms are more complex since they are influenced by the matrix and fiber materials, fiber content and reinforcement type [9,10]. Models for conventional material erosion are not applicable to composite materials due to their heterogeneity and anisotropy. Composites with thermosetting matrix were found to erode in a brittle manner with peak erosion at normal impact. On the other hand, those with thermoplastic metrics were found to erode in duc- 0043-1648/$ – see front matter © 2010 Published by Elsevier B.V. doi:10.1016/j.wear.2010.08.017