Electro-flexure response of multi-functional natural fiber hybrid composites

Abstract

An experimental study was conducted to investigate the electro-flexure response of conductive natural fiber hybrid laminate composites. The composites were composed of laminates of jute and flax fibers, and the composites were subjected to flexural loading for the electrical and bending response. Multi-walled carbon nanotubes were shear mixed and ultrasonicated into the epoxy matrix. Short carbon fibers were reinforced in-between the laminates using “wet flocking” technique. To measure the electrical response under flexural loading, a four-point circumferential probe method was used. A parametric study was conducted to investigate flexural performance and damage sensing by varying carbon fiber lengths (150 and 350 µm) and the carbon fiber densities (500, 1000, 1500, and 2000 fibers/mm2). The addition of carbon fibers decreased the flexural strength for most of the cases, however increased the flexural strain at break for all composites of carbon fiber length of 150 µm. During the nonlinear deformation, the composites of carbon fiber length of 150 µm demonstrated a linear increase in resistance; however, that of carbon fiber length of 350 µm showed increasing slope of resistance. Overall, the composites of carbon fiber length of 350 µm showed lower resistance change at break compared to that of carbon fiber length of 150 µm.

Coupled Flexural-Electrical Evaluation of Additively Manufactured Multifunctional Composites at Ambient Temperature

“…The existing regulatory frameworks, policies, guidance, and industry consensus standards pertain to monofunctional material systems. An experimental investigation was performed for the assessment of electro-flexure response of the conductive natural fiber hybrid composites that were made up of laminates of jute and flax fibers [12]. Test coupons were tested to undergo flexural loading for the electrical and bending responses [12].…”

“…An experimental investigation was performed for the assessment of electro-flexure response of the conductive natural fiber hybrid composites that were made up of laminates of jute and flax fibers [12]. Test coupons were tested to undergo flexural loading for the electrical and bending responses [12]. Four-point circumferential probe method was utilized for measuring electrical response exerted by flexural loading of the test coupons [12].…”

“…Test coupons were tested to undergo flexural loading for the electrical and bending responses [12]. Four-point circumferential probe method was utilized for measuring electrical response exerted by flexural loading of the test coupons [12]. Varying carbon fiber lengths and carbon fiber densities were used for comparative assessment of flexural performance, and deformation detection revealed that an increase of carbon fibers decreased the flexural strength and increased the flexural strain at break for all composites of carbon fiber length of 150 µm [12].…”

“…Four-point circumferential probe method was utilized for measuring electrical response exerted by flexural loading of the test coupons [12]. Varying carbon fiber lengths and carbon fiber densities were used for comparative assessment of flexural performance, and deformation detection revealed that an increase of carbon fibers decreased the flexural strength and increased the flexural strain at break for all composites of carbon fiber length of 150 µm [12]. While the concurrent electro-flexure response was conducted on the traditionally manufactured solid laminate composites, the coupled multifunctional properties of additively manufactured multifunctional composites are not addressed to date [12].…”

“…Varying carbon fiber lengths and carbon fiber densities were used for comparative assessment of flexural performance, and deformation detection revealed that an increase of carbon fibers decreased the flexural strength and increased the flexural strain at break for all composites of carbon fiber length of 150 µm [12]. While the concurrent electro-flexure response was conducted on the traditionally manufactured solid laminate composites, the coupled multifunctional properties of additively manufactured multifunctional composites are not addressed to date [12]. Certification requirements for composite aircraft are separate for assessing the monofunctional properties (e.g., electrical, thermal, structural, etc.).…”