Two-body abrasive behaviour of untreated SC and R-G fibres polyester composites

In this paper, studies have been conducted to investigate the abrasive behaviour of chopped untreated sugarcane fibre (C-SCRP), unidirectional sugarcane fibre (UM-SCRP), and chopped strand mat of glass fibre (CSM-GRP)-reinforced polyester composites (in two different orientations, APO and PO). The effects of chopped fibre length (1, 5, and 10 mm) in C-SCRP, orientation of long fibre mat in UM-SCRP, and orientation of chopped fibre mat in CMS-GRP composites have been determined using SiC of 400 grit size abrasive paper under various loads and sliding velocities. Experimental results revealed that wear resistance of C-SCRP composite, tends to increase with increasing fibre length at lower load by about 44-75% and at higher load by about 17-50% while friction coefficient (0.35-0.1) showed no much dependence on fibre length and decreased significantly with increasing load and fluctuate with increasing speed. UM-SCRP composite gave wear resistance about two times higher than C-SCRP composite due to the fact that long fibres in UM-SCRP composite were well embedded in the matrix and subjected to the abrasion process only at their ends which required high energy to facilitate failure in the sugarcane fibres (SCFs). Beside that lJM-SCRP composite with APO, consistently showed higher wear resistance compared to composite with PO and friction coefficient of similar trends and values as those observed for C-SCRP composite. SEM studies of the worn surfaces indicated that in C-SCRP composite wear mechanism dominated by material removal due to excessive deterioration in both fibre and matrix. While UM-SCRP composite showed less extent of fibre and matrix damage compared to C-SCRP and CSM-GRP composites. Comparison between SCRP and GRP composites revealed that wear resistance of CSM-GRP composite was about 2-3 times greater than UM-SCRP composite and 3-5 times greater than C-SCRP composite suggesting that the ranking order of the three composites tested according to the wear resistance is CSM-GRP (WRAPO > WRPO) >> UM-SCRP (WRAPO > WRPO) >> C-SCRP (WR5mm >> WR10mm > WR1mm). (C) 2008 Published by Elsevier B.V.