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n-Type Si-Ge thermoelectric alloys were prepared using a melt spinning (MS) process, and then the microstructures of the samples were investigated. The alloys studied were ribbon shaped with a thickness of about 30 lm. Scanning electron microscopy (SEM) along with energy-dispersive spectrometry (EDS) and x-ray diffraction (XRD) showed a predictable, homogeneous, fine-grained microstructure at the high cooling rate, different from those of samples created by slow solidification (SS).

316L stainless steel (SS 316L) is quite attractive as bipolar plates in proton exchange membrane fuel cells (PEMFC). In this study, graphite-polypyrrole was coated on SS 316L by the method of cyclic voltammetry. The surface morphology and chemical composition of the graphite-polypyrrole composite coating were investigated by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). A simulated working environment of PEMFC was applied for testing the corrosion properties of graphite-polypyrrole coated SS 316L. The current densities in the simulated PEMFC anode and cathode conditions are around 3×10 9 and 9×10 5 A·cm 2 , respectively. In addition, the interfacial contact resistance (ICR) was also investigated. The ICR value of graphite-polypyrrole coated SS 316L is much lower than that of bare SS 316L. Therefore, graphite-polypyrrole coated SS 316L indicates a great potential for the application in PEMFC.