Finite element analysis (FEA) can be extraordinarily useful to manufacturers doing polymer forming. Having the ability to predict the final shape of a part and the stress and strain state in the material prior to tooling prevents cracking, tearing, unexpected material flow, and other polymer failure mechanisms. In a process similar to that applied to metal forming, iterating designs through simulation optimizes tooling while reducing development time.

While the benefits are great, polymer forming presents challenges to simulation beyond those associated with metals. Often the process involves both contact and large material deformations, both of which make it difficult to converge on an accurate solution. While this kind of simulation is common for metals, many engineers have little confidence in the results when it comes to polymers. Polymers are often highly temperature- and rate-dependent, exhibiting significant stress-relaxation, creep and recovery, and exaggerated forminginduced anisotropy. We illustrate in this article that the technology to model polymers accurately exists, even under large deformations. We explore the steps required to get an accurate model of an example polymer, polyether ether ketone (PEEK), and show the consequences of oversimplification with a tube joining case study.