Dr. ir. Redmer van Tijum - Royal Philips Electronics NV, Drachten, Netherlands
Philips DAP is working with new materials for the cap that acts as a shell around the rotating cutter of their new shavers.
In the manufacturing process, Philips first forms caps from transformation-induced plasticity steel. Because these are too thick and do not have the required precision shape, further manufacturing is required. Philips turned towards electrochemical machining to enable more complex shapes.
ECM works with high currents in thin materials and small electrolyte channels, which leads to high temperatures and even boiling if electrolyte flow is not adequate. This, along with the fact that the cap´s structure also changes over time and is influenced by the high-pressure electrolyte flow, results in significant changes in the cap´s structural integrity, where phenomena such as spring-back can occur. In all, Philips has a complex multiphysics problem to investigate.