Process Parameter Optimization to Improve the Mechanical Properties of Arburg Plastic Freeformed Components

The Arburg Plastic Freeforming (APF) is an additive manufacturing process that allows three-dimensional, thermoplastic components to be produced in layer by layer. The components are generated by depositing fine, molten plastic droplets. One of the main advantages of the APF process is the open machine control. Thus, the process parameters can be adapted and optimized for the individual applications. The optimization is carried out on the basis of a variation of the process parameters using a statistical design of experiments. Relevant process parameters are the layer thickness, the form factor, the raster and delta angle as well as the overlap between the contour and the filling of a layer. In addition, the nozzle and build chamber temperatures are varied. Using this procedure, the effects of the influencing parameters on the mechanical properties and the interactions between the influencing parameters are analyzed and converted into mathematical models. On the basis of the results and the models, guidelines will be developed to assist the user of APF technology in the systematic process configuration for their own applications. The material used is ABS, one of the most frequently used amorphous thermoplastics in additive manufacturing. The mechanical properties are determined on the basis of tensile tests and the characteristic values tensile strength, elongation at break and Young's modulus. The results should show the performance of the APF technology in regard to the mechanical properties.