Influence of fumed silica nanofiller and stacking sequence on interlaminar fracture behaviour of bidirectional jute-kevlar hybrid nanocomposite

The present study aims to examine the influence of nanofiller content and stacking sequence on the interlaminar fracture properties of Jute-Kevlar hybrid nanocomposite. Mode I and Mode II interlaminar fracture properties are characterized by double cantilever beam (DCB) and end notch flexure (ENF) test samples. Bidirectional jute (J) and kevlar (K) fabrics are used as reinforcement. Nanoscaled fumed silica is used as filler reinforcement. Thirteen different types of composites are prepared with varying stacking sequences (i.e., Jute-Jute-Jute-Jute [JJJJ], Jute-Kevlar-Kevlar-Jute [JKKJ], Kevlar-Jute-Jute-Kevlar [KJJK], and Kevlar-Kevlar-Kevlar-Kevlar [KKKK]) and four nanofiller weight fraction (i.e., 0%, 1.5%, 3%, and 4.5%). It is noticed that interlaminar fiber bridging and interlaminar friction are the key factors influencing Mode I and Mode II fracture toughness, respectively. The presence of nanofiller plays a significant role in enhancing the key factors influencing the fracture toughness of the composites. A noticeable improvement in Mode II fracture toughness is found. The composite stacking sequence JKKJ with 3% fumed silica (JKKJ-3) possess maximum Mode II fracture toughness (951 J/m(2)), which is 37% more than kevlar fiber-reinforced composite (694 J/m(2)) (KKKK-0). The evidence of matrix tearing as a result of fiber pull-out, toughened matrix region, and nanofiller wrapping over the fiber are noticed from the optical microscope image of the fractured surface.

Automated summary

The study investigates the influence of nanofiller content and stacking sequence on the interlaminar fracture properties of Jute-Kevlar hybrid nanocomposite. It is found that interlaminar fiber bridging and interlaminar friction are key factors affecting Mode I and Mode II fracture toughness. The presence of nanofiller plays a significant role in enhancing the fracture toughness of the composites, with JKKJ stacking sequence with 3% fumed silica showing the highest Mode II fracture toughness.