What are common post-processing techniques for 3D printed parts?

The correct choice highlights common post-processing techniques that enhance the appearance and performance of 3D printed parts. Sanding involves smoothing out the surface of a printed part to eliminate layer lines and improve its aesthetic appeal. Painting allows for the addition of color and further improves the part’s visual qualities. Chemical smoothing utilizes solvents to dissolve the outer layer of a print, resulting in a smoother finish without the labor of sanding. Thermal treatment, such as annealing, can enhance the mechanical properties of the material, making it stronger and more heat resistant.

The other options each include processes that are not standard post-processing techniques for 3D printed parts. Cooling and heating might occur during the printing process itself rather than as post-processing steps. Reprinting and resizing are more about changing the actual production process than refining already printed components. Welding, cutting, bending, and merging are primarily manufacturing techniques for creating or altering parts from raw materials rather than processes applied specifically to finished 3D printed items. Similarly, polishing and coating can sometimes relate to post-processing, but wrapping and destroying do not have any relevance as standard techniques for 3D printed parts.