Characterization of polyamide powders for determination of laser sintering processability

With the increasing use of laser sintering for the production of end-use parts, there is considerable interest in developing new and improved polymer materials for this technique. Due to the complexity of the process, however, materials are subject to very specific requirements in order to be easy processable. To gain a better understanding of these material requirements, this study investigates the currently most widely used material family: polyamides. Four commercial polyamide sintering grades, including two polyamide-12 grades, one polyamide-11 and one polyamide-6 grade, are characterized, using a new screening approach that encompasses all material properties essential for laser sintering. These include powder characteristics, melt flow, and solidification behavior of the polymer. The study reveals several particular characteristics of polyamides that explain the current popularity of this material family for laser sintering, and may be used as a guideline for finding new materials for the process.