Finite element analysis of additive manufacturing of polymers using selective laser sintering

Abstract

Additive manufacturing (AM) is experiencing widespread adoption in many sectors including aerospace and biomedical. Several research works have already studied AM to ensure high quality final parts can be consistently achieved. To aid in virtually simulating the additive manufacturing processes, companies like ANSYS have developed simulation packages for their finite element software. These packages have been proven to be effective in predicting and minimizing distortion and warping, but their capability in predicting resultant mechanical characteristics requires further investigation. This paper focuses on using ANSYS Additive Suite (AAS) to predict the mechanical performance of polymer parts produced by a selective laser sintering process. Utilizing AAS, the process of additively manufacturing a tensile test specimen was simulated, followed by simulated tensile loading in ANSYS Mechanical. The output of this simulation was then experimentally verified with physical components. The results show that AAS can increase the accuracy of displacement prediction of a part under load within the elastic region with minimal experimentation required. However, it was also observed that the accuracy starts to decrease when approaching the yield point and consequently entering the plastic region due to the complexity of plastic behavior. When designing, the yield point is a critical design parameter and often considered the limit of a material. The process outlined in this paper allows for validation of AM design to be done faster, cheaper, and with more flexibility than possible using experimental or mathematical methods. Should this process be further refined, generative design possibilities will be significantly more powerful.