One of the main characteristics of polymeric materials is that their mechanical properties (i.e. the properties that define their structural integrity) can significantly change with time, load and environmental conditions. In practice, this means that the functionality and the durability of the products manufactured from polymers can substantially change during their life cycle, leading to premature functional or structural failure of the product.
Obviously, the benefits of using polymers in home appliances will have to be balanced with demands for increased durability, which is related to the ability of reliable prediction of long-term behavior of polymer products, that are exposed to different environmental conditions during their use. In line with this, the proposed applicative project’s main objective is to develop a methodology for predicting time-dependent stress-strain behavior of polymer products at low to medium stress levels, at various temperature and humidity conditions. The results will enable the production of home appliances with new design solutions and extended durability with less impact on the environment. The methodology will be based on the exact characterization of the material’s time-dependent properties and the prediction of long-term material behavior coupled with the validated FEM material model.
The methodology will cover non-linear time-dependent processes and will be limited to constant stress loading conditions and applicable to strong material nonlinearities or material failure. Even though polymers’ viscoelastic non-linear behavior has already been investigated, non-linear models have not been used to predict long-term material behavior, which is one of this project’s primary goals.