Influence of raster angle on mechanical properties for FDM 3D-printed PLA polymer

In the present work, the influence of raster angle (0 degrees, 45 degrees, and 90 degrees) on the mechanical properties of 3D-printed polylactic acid has been investigated. Tensile, hardness, and impact tests were conducted for the same. Furthermore, dynamic mechanical analysis has also been conducted. The results revealed that the mechanical properties of specimens printed at a 0 degrees raster angle are better than the specimens printed at other raster angles. Furthermore, dynamic mechanical analysis exposed that the storage modulus is higher for the specimen printed at a 0 degrees raster angle, and the loss tangent (tan delta) is higher for the specimen printed at a 90 degrees raster angle. The yield strength of 45 degrees and 90 degrees raster angles was 7.12% and 19.74% less than the 0 degrees raster angle, respectively. The ultimate tensile strength of 45 degrees and 90 degrees raster angles was 6.46% and 19.10% less than the 0 degrees raster angle, respectively. The 0 degrees printed specimen exhibited maximum impact strength (45 kJ/m2), hardness (17.45 HV), and flexural strength (64.77 MPa), followed by 45 degrees and 90 degrees specimens. Furthermore, the fracture strain was less than 6% for 45 degrees and 90 degrees raster angles at the comparison of 0 degrees raster angle.