The development of feedstock for 3D printing and 3D knitting of continuous carbon fibre composite filaments : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Mechatronics at Massey University, Albany, New Zealand

Abstract

The main purpose of this research was the development of a composite filament comprising of a thermoset resin and long/continuous carbon fibre reinforcement for the use with additive manufacturing applications. Currently, there are composite materials available that consist of fibre reinforcement but none that utilise long/continuous fibre reinforcement with a thermoset resin in a controlled manner. A series of prototypes were developed to determine the production processes required to produce the composite filament. Specimens were produced from these prototypes were subjected to cross-sectional analysis to analyse the quality of composite filament being produced. The results from this research is a production method that consistently produces the composite filament with the desired material properties.

The secondary purpose of this research was to analyse a commercially available 3D printer, the Mark One, that can produce composite parts using long/continuous fibre reinforcement and a thermoplastic matrix. An analysis into the capabilities and limitations of the Mark One was conducted prior to analysing specimens produced by the Mark One. An analysis of the tensile properties of parts produced by the Mark One was conducted using fibreglass and carbon fibre long/continuous fibre reinforcement. Tensile specimens made in accordance with the standard ASTM D638 for Type I specimens were produced and tensile tested. The Taguchi method was used to analyse the effect and contribution that three parameters had on the tensile properties of specimens. Complications with specimens fracturing incorrectly lead to a redesign of the tensile specimens to ensure the specimens would fracture correctly. Several design iterations were tested until a final design was chosen. This final design was used for both fibreglass and carbon fibre specimens. The results from the tensile specimens showed the effect that changing certain parameters had on the tensile properties and the contribution that each parameter had on the tensile properties produced using the Mark One. These results were confirmed by producing tensile specimens using the optimal combination of parameters and provided insight into the capabilities of the Mark One.