The dry sliding friction and wear behavior of epoxy hybrid composites reinforced with glass fibers and a varying amount of potassium titanate whiskers (PTWs) fabricated by vacuum hand layup method were studied. The influence of normal load, sliding velocity, and whisker content on both friction coefficient and specific wear rate was investigated on a pin-on-disc machine. The tests were conducted at ambient conditions based on the 3 × 3 (3 factors at 3 levels) full factorial design. Analysis of variance (ANOVA) was performed to obtain the contribution of control parameters on friction coefficient and wear rate. The density and hardness of the composites were found to be enhanced with the PTW loading. The friction coefficient and wear resistance of the hybrid composites were found to be improved with the whisker content and were also greatly influenced by normal load and sliding velocity. A correlation between dry sliding wear behaviors of composites with wear parameters was obtained by multiple regressions. The worn out surface of selected samples was observed under scanning electron microscope (SEM) to identify wear mechanisms. This study revealed that the addition of the ceramic microfillers such as PTW improves the wear performance of the epoxy/glass polymer composites significantly. 1. Introduction Polymer matrix composites (PMCs) are nowadays considered as novel materials in many engineering applications due to the combination of advantages such as high strength to weight ratio, high stiffness to weight ratio, ease in processing, cost reduction, and excellent performance [1]. A traditional route followed from several decades to widen the scope of PMCs is by means of adding micro- or nanofillers into polymeric systems having the fibrous reinforcement. The combinative effects of adding the fibers and the fillers into polymers have shown encouraging results in terms of improvements in mechanical, thermal, and tribological properties [2]. The fillers employed for modifying the tribological behavior of polymers are mostly inorganic compounds. Among the several inorganic ceramics, potassium titanate whisker (PTW, K2O·6TiO2) is the only multicomponent ceramic which has gained a widespread use as a friction material. These relatively cheap whiskers have good thermal durability, chemical resistivity, and dispersibility and have been used as reinforcement material in plastics, ceramics, heat insulating paints, and automotive brake linings [3]. These whiskers have very small diameters; hence, they are free from any internal flaws or imperfections. Because of
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