Surface pre-treatment of aluminum alloys for the deposition of composite materials

Abstract Experiments reported in this paper issue on the behavior of two types of aluminum alloys (A2014 and A7075) before and after surface treatments. Each sample of alloys was cleaned and degreased in acetone by ultrasound, and the chemical roughening process involves two steps: etching in NaOH solution and desmutting in HNO3 solution, followed by washing with deionized water to remove the secondary reaction products. The microstructural characterization and morphological analysis of the alloys surface before and after treatment processes were investigated by OM, FE-SEM, EDX and FTIR. Also, the effect of solutions on surface roughness of aluminum alloys was determined by variation of weight and thickness according to the applied process, and the hydrophilic or hydrophobic character was measured by determining the contact angle. The obtained results highlight the need for the alloy surface processing steps in order to ensure adhesion and good compatibility with different types of composite materials.