During the process of synthesizing nanometre alumina reinforced laser clad layer on an aluminium alloy surface, a chemical reaction occurs. The reaction occurs at free-hydroxyl groups on the surface and protects the aluminum alloy surface from corrosion. In addition, a layer of nanometre alumina reinforced laser clad is formed, which has wear resistance properties of about five times compared to a single layer.
The present invention relates to a novel method for synthesizing a nanometre alumina reinforced laser clad on an aluminium alloy surface. It includes the steps of immersing the aluminium alloy surface in a bath of 2,2,2-trifluoroethanol, then spraying the polyamide-6.6 coating on the surface and then dissolving the polymer layer to access the interface. The method allows access to bound molecules and facilitates the removal of contaminant materials.
Three samples were analyzed by XPS and ToF-SIMS. The percentage of aluminum in the survey spectra is similar for the UV-cleaned and the heated samples. However, the ion intensities of some ions are lower in the weld than in the outside. Some ion intensities are also comparable to the intensities of other ion types in the weld.
A first contribution is at 531.4 eV and is interpreted as aluminum oxide. A second contribution at 532.4 eV is interpreted as aluminum hydroxide. The last contribution is at 533.5 eV and is interpreted as an organic molecule.
These contributions are in good agreement with previous experiments on welded samples. It is suggested that the C-O-Al bond is formed. The chemical bond at the interface can be studied and studied the impact of surface pretreatment.