Effect of infill on tensile and flexural strength of 3D printed PLA parts

Abstract

Development in open source three-dimensional (3D) printing has generated interest for creating low-cost customised objects; in both personal and commercial. In the 3D printing process, the quality and cost of the objects produced are normally influenced by the processing parameter. One of the parameter is infill patterns. Infill patterns can be used to reduce material usage and printing time. Various infill patterns are available in the 3D printing software. Four different infill patterns were used to evaluate the mechanical properties of fabricated parts. Open source 3D printer was used to print five PLA specimens for each different infill pattern. Tensile and 3-point bending tests were performed on the printed parts in order to determine the tensile and flexural strength. The mechanical strength of printed parts is influence by different infill patterns. The results obtained indicated that Rectilinear pattern has the highest tensile and flexural strength. The average tensile strength of Rectilinear is 19.1 MPa with average modulus elasticity of 10.51 GPa, whereas the average flexural strength of Rectilinear is 24.4 MPa with average tangent modulus elasticity of 0.359 GPa.