Die design optimization of die casting for fabrication of fuel cell aluminum bipolar plate with micro-channel through casting simulation and experimental investigation

In vacuum die casting, we require a high quality die design for fuel cell bipolar plates to prevent unfilled phenomena, turbulent flow, and porosity. We have designed a die for thin plate die casting using two geometric shapes. In addition, we propose a new overflow system based on numerical simulation, and conducted actual vacuum die casting experiments. An optimal die design consists of seven overflows at the end of the cavity and three overflows at each side wall of the cavity. In our experiment, the molten metal that passed the gate and reached the side wall flowed into the side overflow, no turbulent flow occurred, and the filling behavior and are uniform. In addition, partially solidified molten metal passing through the channel was perfectly eliminated by overflow without back-flow. To validate the proposed approach, a good quality sample was manufactured using the optimal die design with the proposed overflow system.