| A pulsed YAG laser installation was used to produce surface treatment on Al18B4O33w/2024Al composite. The effect of laser power, laser scanning rate and pulse duration on the microstructures and corrosion behaviors of the composites has been studied.The microstructure of a laser treated Al18B4O33w/2024Al composite has been investigated using transmission electron microscope (TEM), low-angle (glancing angle) X-ray diffraction (XRD) techniques.Various surface microstructures were observed in the laser treated composite. The Al18B4O33 whisker on the surface of the composite was decomposed during laser surface melting, various decomposition produces were studied in the laser treated composite. Eutectic phases and the precipitation in the matrix of the composite with laser-treated were observed. The main phases detected in the molten zone were aluminum and decomposition produces Al2O3.Results indicate that laser power has significant influences on both of the microstructure and the corrosion resistance. The difference in morphological transformations was observed on the surfaces of the laser-treated specimens. An increase in Epit was obtained after laser-treated for the composite. The improvement was considered primarily due to the reduction both ofreinforcement Al18B4O33 whisker and intermetallics CuAl2 on the surfaces of the laser-treated composites, which were found to be sites for pits nucleation. Moreover, the specimen with the optimal laser parameter treated exhibited a much greater resistance to corrosion than the other specimens with laser treated. This was attributed to the formation of the homogeneous and defect free microstructure in the laser-modified layer.
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