Tribological performance of paddy straw reinforced polypropylene (PSRP) and unidirectional glass-pultruded-kenaf (UGPK) composites

In standard preparation and fabrication of natural-fibre embedded composites, 5 wt. % of natural fibre is enough to strengthen and homogenized in parental matrix as the mechanical strength was observed to increase by more than 25% of pure matrix. Hence, paddy straw and kenaf has been a potential candidate in northern region of Malaysia due to its abundance and easily replenished. A unidirectional glass-pultruded-kenaf (UGPK) and paddy straws reinforced polypropylene (PSRP) was studied focusing on its tribological performance. Meanwhile, friction and wear properties were examined using pin-on-disc machine under ambient temperature with dry contact condition. The tests were conducted at various sliding velocities (1.178-2.749m/s) and applied normal loads (9.82-19.64N). The results showed that specific wear rate and friction coefficient decreased with increasing applied normal load and sliding velocity, but the applied normal load was more influential. The coefficient of friction ranges from 0.5 to 4 and wear rate varies from 0.5 to 4 x 10-5 mm3/Nm for PSRP. The friction coefficient of UGPK is within a range of 2.76 to 4.54 at the given test parameters while its wear rate ranging from 0.8 to 1.79 x 10-5mm3/Nm. The failure mode observed during the test was micro-buckling and followed by splitting while fiber-matrix interfacial failure occurred