Michael Van den Eynde

Influence of temperature on the flowability of polymer powders in laser sintering

Powder flowability is a determining factor in many industrial applications. Multiple techniques exist for assessing whether a powder flows adequately or not. However, most of these techniques occur at ambient conditions, rather than the actual processing temperature. Especially for laser sintering (LS), in which polymer powders are spread at a strongly elevated temperature, thermal effects cannot be ignored. This work expands an existing set-up, the powder spreader, which is designed for analysing LS powder flowability, to include temperature control. The focus in this paper lies on the additions made to the set-up. Tests on the standard PA12 2200 of EOS illustrate the use of this expanded technique, as well as the level of temperature control attained.

3D Printing of Poly(lactic acid)

Poly(lactic acid) has received considerable interest in biopolymer-related research because of its excellent biocompatibility and sustainability. With the advent of new processing routes based on additive manufacturing technologies – commonly called 3D printing – applications of PLA have become more and more widespread, especially in the biomedical field (e.g., as scaffolds for tissue engineering). This review focuses on three of the most important additive manufacturing routes: extrusion-based 3D printing techniques, powder-based laser sintering, and stereolithography. For each of these methods, we discuss the processing conditions and their effect on the end use of PLA.