Wear 267 (2009) 1405–1414 Contents lists available at ScienceDirect Wear j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / w e a r Investigations on the influence of graphite filler on dry sliding wear and abrasive wear behaviour of carbon fabric reinforced epoxy composites B. Suresha a,∗ , Siddaramaiah b , Kishore c , S. Seetharamu d , P. Sampath Kumaran d a Department of Mechanical Engineering, The National Institute of Engineering, Mysore 570 008, India b Department of Polymer Science and Technology, Sri Jayachamarajendra College of Engineering, Mysore 570 004, India c Department of Materials Science and Engineering, Indian Institute of Science, Bangalore 560 080, India d Materials Technology Division, Central Power Research Institute, Bangalore 560 080, India a r t i c l e i n f o Article history: Received 1 September 2008 Received in revised form 11 January 2009 Accepted 11 January 2009 Keywords: Carbon-epoxy composites Graphite filler Dry sliding wear Two-body wear Wear mechanisms a b s t r a c t In this experimental study, the dry sliding wear and two-body abrasive wear behaviour of graphite filled carbon fabric reinforced epoxy composites were investigated. Carbon fabric reinforced epoxy composite was used as a reference material. Sliding wear experiments were conducted using a pin-on-disc wear tester under dry contact condition. Mass loss was determined as a function of sliding velocity for loads of 25, 50, 75, and 100 N at a constant sliding distance of 6000 m. Two-body abrasive wear experiments were performed under multi-pass condition using silicon carbide (SiC) of 150 and 320 grit abrasive papers. The effects of abrading distance and different loads have been studied. Abrasive wear volume and specific wear rate as a function of applied normal load and abrading distance were also determined. The results show that in dry sliding wear situations,for increased load and sliding velocity,higher wear loss was recorded. The excellent wear characteristics were obtained with carbon-epoxy containing graphite as filler. Especially, 10 wt.% of graphite in carbon-epoxy gave a low wear rate. A graphite surface film formed on the counterface was confirmed to be effective in improving the wear characteristics of graphite filled carbon-epoxy composites. In case of two-body abrasive wear, the wear volume increases with increasing load/abrading distance. Experimental results showed the type of counterface (hardened steel disc and SiC paper) material greatly influences the wear behaviour of the composites. Wear mech- anisms of the composites were investigated using scanning electron microscopy. Wear of carbon-epoxy composite was found to be mainly due to a microcracking and fiber fracture mechanisms. It was found that the microcracking mechanism had been caused by progressive surface damage. Further, it was also noticed that carbon-epoxy composite wear is reduced to a greater extent by addition of the graphite filler, in which wear was dominated by microplowing/microcutting mechanisms instead of microcracking. © 2009 Elsevier B.V. All rights reserved. 1. Introduction The need for the use of newer materials to combat wear situations has resulted in the emergence of polymer based com- posite materials. Fiber reinforced polymeric composites are the most rapidly growing class of materials, due to their good com- bination of high specific strength and specific modulus.They are widely used for a variety of engineering applications.The impor- tance of tribological properties convinced many researchers to study the friction and wear behaviour and to improve the wear resistance of polymeric composites.For fiber reinforced polymer matrix composites the process of material removal in dry slid- ing condition is dominated by four wear mechanisms, viz., matrix ∗ Corresponding author. Tel.: +91 821 2480475/2481220; fax: +91 821 2485802. E-mail address: sureshab2004@yahoo.co.in (B. Suresha). wear, fiber sliding wear, fiber fracture and interfacial debonding [1]. Wear is defined as damage to a solid surface, generally involv- ing progressive loss of material, due to relative motion between that surface and contacting substance or substances. The five main types of wear are abrasive,adhesive,fretting,erosion and fatigue wear, which are commonly observed in practical situations. Abra- sive wear is the most important among all the forms of wear because it contributes almost 63% of the total cost of wear [2]. Abra- sive wear is caused due to hard particles or hard protuberances that are forced against and move along a solid surface [3]. In two- body abrasion, wear is caused by hard protuberances on one surface which can only slide over the other. Polymer and their composites are finding ever increasing usage for numerous industrial applica- tions such as bearing material,rollers, seals,gears,cams, wheels, and clutches [4]. Different types of polymer show different friction and wear behaviour. However, neat polymer is very rarely used as 0043-1648/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.wear.2009.01.026