Approach to Defining the Maximum Filler Packing Volume Fraction in Laser Sintering on the Example of Aluminum-Filled Polyamide 12

Laser sintering is one of the most popular additive manufacturing techniques that uses thermoplastic polymer powders to generate layer-by-layer complex structures. Despite its broad application, some limitations exist restricting its further development. One such restriction is a narrow assortment of commercially available materials that would allow the production of the parts with the desired mechanical characteristics, which is the case with the widely used Polyamide 12 (PA12). Reinforcement of a matrix polymer with metal particles is routinely performed to achieve better mechanical properties. In this work, a PA12 system enhanced with a 35% volume ratio of aluminum was investigated. Mechanical characteristics, e.g. elastic and flexural moduli, were examined with respect to variation of manufacturing process parameters. In addition, a new methodology was tested, which should help determine the maximum filler packing volume fraction corresponding to the highest mechanical characteristics of a polymer-filler mixture.