Mechanical and Tribological Behavior of Vinyl Ester Hybrid Composites

An attempt has been made to explore the effect of hybrid reinforcement on mechanical properties and dry sliding wear behavior of vinyl ester (VE) composites. Vinyl ester reinforced with alkali treated coir fibers (CF-VE), silanated aramid fibers (AFs) leading to fibridization and inclusion of coconut shell powder (CSP) with various weight proportions has been prepared resulting in hybridization. Effectiveness of treated fibers and CSP on mechanical and wear behavior of VE and their hybrids was evaluated. The density and hardness values of CF-VE composite increased steadily with inclusion of AFs and CSP. The tensile strength increased from 52 MPa at 0 wt.% AFs inclusion to a maximum of 76 MPa at 15 and 5 wt.% of AFs and CSP content. Further, it increased to a maximum of 78 MPa at 5 and 10 wt.% of AFs and CSP in CF-VE composite. The specific wear rate decreased more rapidly with the CSP content. Hence, it is deduced that hybrid VE (15CFs+5AFs) composite with 10 wt.% CSP is more effective against sliding wear. The type, geometry and dispersion of reinforcements contribute to the increased wear resistance. These results are important for the development of new composites incorporated with surface treated reinforcing materials such as CF and CSP, which will have significant application in automotive sliding or bearing components.