Study on the Properties of Fuel Cell 304 Stainless Steel Bipolar Plates with Flow Channels Milled Using Different Methods

摘要

Various materials are currently used as bipolar plate flow channel substrates in proton exchangemembrane fuel cells (PEMFCs): stainless steel, carbon steel, copper, aluminium, graphite, etc.Stainless steel has the best corrosion resistance among these materials but is more difficult to machine.Stainless steel exhibits the following characteristics during cutting: severe processing-inducedhardening, a large cutting resistance, a high cutting temperature and chips that do not break easily andare prone to adhesion and tool wear. In the experiments reported here, SUS304 stainless steel was usedas a substrate to explore the impact of using different methods, rotation rates, feed rates and coolingmethods to mill flow channels for the subsequent anti-corrosion treatment of the specimens. Aftermilling, the flow channels and the specimens were plated with chrome-carbon (Cr-C) to improve thecorrosion resistance and conductivity of the substrates. After plating, the specimens that werefabricated using the high-speed milling machine performed better in all aspects and exhibited overallbetter corrosion resistance and electrical properties, as measured by potentiodynamic and potentiostaticpolarization tests, than the other specimens. The results of our study can serve as a reference for theprocessing of PEMFC bipolar plates.