Currently, the automotive sector is exploring the feasibility of replacing metals with composite materials for structural and non-structural applications. This is mainly driven by the demand for lighter and increasingly complex components, which will be extremely difficult to fabricate with the traditional metal forming approaches. This prompted the need for exploring textile reinforced composite materials, where they stand out about their ability to allow complex designs with high specific strength and stiffness. Which further helps to reduce mass and increase fuel efficiency. However, a disadvantage right now is the use of composites is limited by an inability to accurately analyse and predict these composite structures for its mechanical performance. This thesis presents methodology employing finite element techniques for predictive modelling of textile reinforced composite materials by considering the process simulations. The Building Block approach is introduced and implemented as a guideline, to efficiently substantiate the durability and performance of the component design sequentially. FEA simulation of a composite component was done using two composite failure criterions for comparison, Crasurv (modified Tsai-Wu) and Hashin; after completing a detailed material characterisation and card fitting for creating FE material. The results of the structural simulations are compared against experimental results, which is kept as a benchmark for future comparisons and review. The next step was to conduct process simulations to analyse the composite forming process to investigate the locally varying microstructure to account for the anisotropic behaviour in the composite part during its production that can alter the structural integrity of the component. An additive split between isotropic, elasto-plastic matrix and anisotropic hyper-elastic fibers material card is used in LS-Dyna explicit solver for conducting process simulations. A detailed material characterisation was done on the textile reinforced fabric and the composite laminate at forming temperature to study its tensile, shear, frictional and bending properties. The process simulation helps to obtain reliable structural simulation models by mapping.
|Titolo:||Modelling and testing of thermoplastic composite components using Building Block approach integrating process simulation.|
|Data di pubblicazione:||23-mag-2018|
|Appare nelle tipologie:||8.1 Doctoral thesis Polito|