Surface Analysis of Surface Finished Aluminum Alloys with a Low Outgassing Property

Abstract

Optimized mechanical grinding (OMG) was developed as a low outgassing surface finishing for aluminum alloys (A5052). Surface morphology and depth profile for aluminum alloys with four types of surface finishes, i.e. conventional mechanical grinding (MG), mechanical grinding with optimized process (OMG), combination of mechanical grinding and chemical polishing (MG＋CP) and combination of optimized mechanical grinding and chemical polishing (OMG＋CP), were investigated using Atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The surfaces of MG and MG＋CP were rough, whereas OMG and OMG＋CP were smooth. The composition of the surface layer of MG was composed of Al₂O₃ and γ–AlOOH, whereas OMG, MG＋CP, and OMG＋CP was composed of Al₂O₃. Therefore, OMG was considered to have low outgassing property due to the smooth surface and thin surface oxide layer compose of Al₂O₃, which were originated from the small surface alteration by the processing.