Effects of Overmolding Process Parameters on Bondzone Quality

Urban air mobility (UAM) vehicles refer to small sized systems that transport people or cargo by air. In recent years, the interest in UAM vehicles has risen to combat traffic congestion, provide faster delivery times, or provide easier access to remote places. To meet potential future demand, traditional aircraft manufacturers must introduce manufacturing technologies that can cope with high production rates. One manufacturing technology aircraft manufacturers are investigating is overmolding, a manufacturing technology common to the automotive industry. Overmolding combines the manufacturing and assembly cycles into one by injection molding a component on top of a substrate. The quality of the bond between the injection molded component and substrate is of great importance and will impact the strength of the part. Overmolding can increase the production rate significantly, but, it has seen little use for aerospace load-bearing applications with one of the concerns being the limited understanding of the bond characteristics. This study aims to characterize the effects of overmolding process parameters such as, injection pressure and temperature, packing temperature and pressure, and mold temperature, as well as material properties (like, melt temperature and viscosity) on bond strength using Moldex3D and ABAQUS. Moldex3D is used to determine the effects of the process and material parameters on the temperature distribution at the bond zone, while ABAQUS is used to predict the failure load of a T-stiffener overmolded on a substrate