1 Influence of material structure properties on sliding contact performance of CGRP composite

In the current work, an experimental investigations on friction and interface temperature of chopped strand mat glass fibre (type-R) reinforced polyester (CGRP) sliding against smooth stainless steel are presented. Pin-on-disk (POD) apparatus was used to perform the experimental tests under dry contact condition. Several tribo-parameters are considered, namely load (30, 60 & 90N), sliding velocity (2.8, 3.52 & 3.9m/s) and sliding distance (0-2.51km). In addition, the CGRP composite was investigated in two different orientations of chopped strand mat (CSM) glass fibre in the matrix, with respect to sliding direction and counterface, i.e. Parallel (P) and Anti-parallel (AP). Friction forces and interface temperatures were measured simultaneously. To observe the damages feature on the worn surface of CGRP composite, scanning electron microscopy (SEM) is used. The results of friction coefficient and interface temperature were presented as function of sliding distance at different loads, velocities and orientations. Experimental results revealed that orientations of CSM glass fibres and test parameters played a major role in friction and interface temperature behaviour. Tested parameters (load, sliding distance, sliding velocity and orientations of CSM glass fibre in matrix) have an essential influence on the friction coefficient and interface temperature results of the CGRP composite. AP-orientation produced high friction coefficient (0.5-0.6) and interface temperature (29-50oC) in compared to P-orientation. High damage on the CGRP surface were found when the CGRP tested in AP-orientations at higher load and velocity, i.e. fibre break, peels off, debonding, polyester deformation. 1