Lazy thermal annealing of material extrusion-based 3D-printed PLA specimens

Material extrusion (ME)-based 3D printing process is widely used nowadays, and the created parts can be used for rapid prototyping or as a finished part for industrial representatives, but the technology is also popular among home users. One of the greatest limitations of the parts created by ME is the mechanical anisotropy resulting from the extrusion process. The inter- and intra-layer adhesion makes the parts prone to early failure. By thermal post-processing, this kind of bond can be improved; however, that would need an investment of some new equipment/machines. In this article, a “lazy annealing” thermal post-processing method is presented, where the parts are cured on the 3D printer to increase their mechanical resistance. According to the results, even with this simple method, a significant increment can be achieved, but it has less effect on the infill patterns.