Investigation of mechanical behaviors of zirconia-alumina nanocomposite coating applied on Al 2024 by sol- gel method

Nanocomposite ceramic-based coatings, due to its high hardness and wear resistance, are improved wear behavior of aluminum and its alloys. In this study, zirconia nanocomposite coating applied on Al 2024 by using sol-gel method and dip coating process with the use of zirconium propoxide and aluminum tri-sec butylate. Then phase, structural and morphology properties of coatings evaluated by using GIXRD, FTIR, FESEM, AFM, as well as nano-mechanical properties of coatings were investigated by using nano-scratch and nano-indentation at two different loads, such as 50 and 60 mN. Results indicated that the formation of a homogeneous, smooth and low cracked ziconia-alumina nanocomposite coating with a thickness of approximately 800 nm. The presence of alumina cause to enhance the mechanical properties such as hardness and elastic modulus to 1.15 and 15 GPa, respectively, resulting in improve the wear behavior of coating with the friction coefficient of 0.51 and dominate the abrasive with shear mechanism.