Inverse heat transfer optimization of stamping with over-molding process involving high performance thermoplastic composites: experimental validation

摘要

Heat transfer plays a major role when designing manufacturing processes involving high-performance thermoplastic composites. Indeed, thermal parameters have a direct impact on part's quality and process productivity. Balance between these aspects remains a subject of study since more complex materials and hence more intricate processes emerge. Over the past decades, different optimization approaches have been proposed to overcome this challenge. Most of these investigations focused on a single stage of the process and the transformation of mono-materials. This research proposes a thermal design methodology that could be applied in all stages of the manufacturing process but also to a multi-material parts. The aim is to reduce defects inside manufactured pieces through the right configuration of thermal-related parameters, as temperature or heat flux distribution around the manufactured part at each stage. The designed methodology uses an inverse optimization algorithm based on a conformal cooling approach as proposed by Agazzi et al in Appl Thermal Eng 52(1):170-178, (2013) and Hopmann et al (2019). A 1D case is proposed to validate the methodology by comparing numerical results with experimental ones. A further extension to a 2D axisymmetric case is presented. Results for both 1D and 2D cases show an improvement of thermal profiles within the part. Temperature gradients could be reduced without decreasing bonding between elements for time dependent design variables. The thermal profile around the part could be used later to select the most adapted technology or cooling system.