Tensile behavior of MWCNT enhanced glass fiber reinforced polymeric composites at various crosshead speeds

Fiber reinforced polymeric (FRP) composite materials are subjected to different range of crosshead speeds during their in-service life. The work has been focused to investigate the effect of carbon nanotube (CNT) addition in glass fiber reinforced polymer (GFRP) composite on tensile behavior. The Control GFRP composites and CNT modified composites were tested at different crosshead speeds viz. 1, 10, 100 mm/min. CNT modified matrix was processed with epoxy as a matrix materials and multi-walled carbon nanotube (MWCNT) as a filler with different MWCNT content (i.e. 0.1, 0.3 and 0.5 wt. %). Increase in the CNT content upto 0.3% the tensile strength increasing for all the crosshead speeds as compared to the control GFRP composite. The tensile strength are dependent on the CNT content in GFRP composite. It has been observed that addition of 0.1% CNT and 0.3% CNT enhanced the tensile strength by 6.11% and 9.28% respectively than control GFRP composite. The tensile modulus is found to be mostly unaffected on an optimum CNT content in the GFRP composite. The tensile strength of control GFRP and all CNT modified GFRP composites were found to be crosshead speed sensitive and increased with increasing crosshead speeds in the aforesaid loadings. However, slight decrease in tensile modulus was observed with addition of CNT due to agglomeration of the CNT in the polymer matrix composites. The DSC analysis was also carried out to understand the effect of the CNT content on the glass transition temperature (Tg) of GFRP composites. Different failure patterns of GFRP composite tested at 1, 10, and 100 mm/min crosshead speeds were identified.