Determination of optimum printing direction of the polycarbonate parts produced by additive manufacturing

Abstract In this study, the effect of printing direction on the tensile properties of polycarbonate (PC) parts produced using a 3D printer was investigated. A total of 9 samples were produced with printing directions of 0°, 45° and 90° with infill density of 20%. Tensile tests were carried out to determine the maximum tensile strength (UTS) of the samples. As a result of the research, it was determined that the samples produced in the same direction as the tensile direction (0° printing direction) had the highest strength values; on the other hand, samples produced in the 90° printing direction have the lowest strength values. While the ultimate tensile strength values for samples produced in 0° printing direction were measured respectively as 22.4 MPa, 21.6 MPa and 20.7 MPa; as 7.1 MPa, 9.1 MPa and 9.2 MPa in 45° printing direction; it was determined as 7.2 MPa, 5.4 MPa and 5.8 MPa in the 90° printing direction. In addition, UTS/mass ratios were calculated by measuring the mass of the samples after the tensile test. According to the results obtained, samples in the 0° printing direction have the highest UTS/mass ratio compared to other printing directions, making them the most durable option for applications requiring lightweight structures. Tensile samples produced in FDM were analyzed with the finite element method (FEM) and analysis results were found to be equivalent to physical tests. This study contributes to examination of the influence of 3D printing direction, especially exposed to tensile, on material properties, and provides important information for the production of lightweight and high strength PC components in industries such as medicine, aerospace and automotive.