Tensile properties and failure behaviour of continuous kevlar fibre reinforced composites fabricated by additive manufacturing process

Abstract

ABSTRACT Fused deposition modelling (FDM) is one of the most promising Additive Manufacturing (AM) techniques. FDM technique is capable to print continuous fibre reinforced composite (CFRP). Both researchers and the industrial community are becoming interested in this area. In the present work, Kevlar fibre reinforced composite (KFRCP) was fabricated using Fused deposition modelling (FDM) technique. Onyx material is used as matrix material and continuous kevlar fibre as reinforcement. In this present work influence of the following parameters has been investigated: effect of an increase in kevlar fibre reinforcement starting from 0, 2 to 10 layers in a step-wise manner on tensile strength. An effect of change in kevlar fibre direction, as well as configuration (isotropic, concentric pattern) on tensile strength by fixing 10 layers of kevlar reinforcement. A tensile test was conducted on the specimen in compliance with ASTMD3039. Young’s modulus and stress had been calculated based on experimental results. It was observed that the overall strength of KFRCP was twenty times more compared to virgin CFRP (only onyx). Kevlar fibre has the poorest wettability with the matrix. Poor wettability and lack of impregnation between fibre and matrix result in delamination. Furthermore, delamination with an increase in reinforcement in the FDM process is also discussed. The results obtained will aid designers to select appropriate fibre direction and orientation while developing FRCP parts to prevent delamination.