Effect of post-heat treatment on the mechanical and surface properties of nylon 12 produced via material extrusion and selective laser sintering processes

The utilisation of additive manufacturing is essential in the production of intricate and complex parts that cannot be manufactured using traditional manufacturing methods. Despite the complexity of the manufacturing process, parts produced using techniques such as FDM and SLS may include imperfections that diminish the strength of the final products. Post-processing was necessary to increase their strength despite the fact that defects are unavoidable due to the use of advanced manufacturing techniques. Post-heat treatment of FDM- and SLS-printed specimens is assessed using mechanical testing and microscopic analysis. Both the FDM- and SLS-printed parts were discovered to be significantly impacted by post-heating, with the SLS-produced parts being more impacted. After undergoing the heat treatment process, the FDM-printed parts exhibited an average tensile strength of 39.11 MPa, a surface roughness of 2.13 mu m, a Shore D hardness of 58.79, and a specific wear rate of 21.21 x 10-5 kg/Nm. After undergoing the heat treatment process, the SLS-printed parts exhibited an average tensile strength of 28.06 MPa, a surface roughness of 2.4 mu m, a Shore D hardness of 49.48, and a specific wear rate of 17.49 x 10-5 kg/Nm. The FDM- and SLS-printed components' tensile and hardness properties increased by 21.98 and 6.5%, respectively. The FDM-printed parts' surface roughness and wear rate were lowered to 24.83 and 21.1%, while the SLS-printed parts' were reduced to 51.67 and 50.3%. It proved that SLS-printed components are highly influenced, and that thermal treatment dramatically improved their mechanical properties.