An assessment of flexural performance of liquid nitrogen conditioned glass/epoxy composites with multiwalled carbon nanotube

The objective of the present investigation is to study the alteration in flexural performance of glass/epoxy (GE) composite with and without multiwalled carbon nanotube (MWCNT) after liquid nitrogen conditioning. The epoxy resin was first modified by 0.1, 0.3, and 0.5 wt% MWCNT, which was then used along with E-glass fibers to fabricate laminates. Flexural strength and modulus were evaluated by 3-point bend test. Out of these four compositions, the maximum strength in the as-fabricated condition was obtained for GE composite with 0.1 wt% CNT, which is 32.74% higher as compared to GE composite. Decrease in strength and modulus was observed for short time span of liquid nitrogen conditioning i.e. 0.25 h. Long cryogenic conditioning resulted in increment in strength. To understand the failure mechanisms, post failure analysis was carried out using scanning electron microscope. The design parameters are calculated using Weibull distribution model.