Effects of fiber on the fracture behavior of 3D-printed fiber reinforced nylon

Abstract

Considering capabilities of additive manufacturing (AM), its application has been increased in numerous industrial and research projects. The three-dimensional (3D) printing techniques have been used for fabrication of prototypes and functional end-use products with complex geometries. 3D printing of continuous fiber reinforced components is a promising composite fabrication process which can be utilized in different industries. This paper evaluates the mechanical performance and fracture behavior of reinforced and unreinforced parts fabricated by 3D printing technology. To this aim, nylon and fiberglass materials were used to print specimens based on material extrusion technique. The test coupons were designed with different fiber volumes and saved in “.stl” format, and later molten material was used to print the specimens in layers. Since there is a possibility to improve the strength of 3D-printed parts by incorporation of fibers, here we used fiberglass to improve the mechanical performance of additively manufactured parts. Based on a series of experimental practices, mechanical properties of reinforced and unreinforced parts were determined. In detail, fracture load and curves representing the relationship between stress and strain were documented. In addition, effects of fiber volume on the fracture resistance of the parts were determined. The outcome of this study can be used for design of 3D-printed fiber reinforced composites with superior fracture resistance.