Optimal short carbon fiber‐reinforced polyamide 6 composites with lifted high strength and toughness for fused filament fabrication

Abstract

The high‐strength and lightweight carbon fiber‐reinforced composites are widely used in various industries. Fused Filament Fabrication (FFF), the most cost‐effective Additive Manufacturing (AM) technology, has gained significant application advantages in the industry. The objective of this study is to improve the toughness of the carbon fiber‐reinforced polyamide composites used for FFF. In this work, HDPE was selected to reduce the hygroscopicity of PA6 while lowering the cost, carbon fiber was introduced to reinforce the PA6/HDPE blend. The elastomer POE‐g‐MAH was applied to increase the toughness of the composites as well as to improve the compatibility of the incompatible system of PA6/HDPE. Mechanical tests and micromorphology observation were carried on the FFF printed samples. The test results show that when 20 phr POE‐g‐MAH was added, optimum mechanical properties were obtained for the composites with about 18.9 wt% carbon fiber content. The tensile strength reached 94.1 MPa, and the notched impact strength reached 21.0 kJ/m2, which were 180.8% and 610.7% higher than that of the neat PA6, respectively. It is applicable for various applications that require high‐impact strength, including automotive parts and some machine components.Highlights The PA‐2CF‐C20 composite exhibits high strength and high toughness, the tensile strength reaches 94.1 MPa and the notched impact strength reaches 21.0 kJ/m2. Successfully prepared cost‐effective and high‐performance filament for FFF 3D printers.