Barring a few exceptions, 3D printed parts, when used under normal conditions, will remain relatively stable over time. The deterioration in properties primarily depends on the material and the end-use application of the printed part. Nylon (PA 2200) and UV coated ABS materials have good mechanical stability among the available thermoplastics and resins for 3D printing. However, the durability and longevity of 3D printed parts still remains inferior to injection molded and machined parts.
Since PLA material has the lowest glass transition temperature (60 ⁰C) among the available 3D printing materials, it is most susceptible to deformation under hot conditions. When exposed to high temperatures, it will become soft and will start drooping, degrading the mechanical properties of the printed part. However, when stored under normal conditions, it will remain stable with no noticeable change in properties.
Photopolymer resins get cured when exposed to UV light. Post printing, some amount of curing still continues as the parts are exposed to UV light, which results in the parts getting slightly more brittle. If the resins are transparent or clear resins, continuous exposure to UV light will also result in the formation of a yellow tarnish.
Full-color prints in sandstone material may lose the strength and richness of their colors over time as the parts are exposed to humidity and light. To prevent this, the prints are treated with a UV protective coating post printing, which increases the durability and the longevity of the printed colors.
