A self-lubricating composite coating on 6061 aluminum alloy surface with an intermediate anodised layer

A self-lubricating AAO-Cu/Ni-P composite coating was deposited on the surface of 6061 aluminum alloy. An anodized intermediate layer (AAO) was introduced to enhance the adhesion and wear resistance of the coating. The microstructure, element distribution, and properties of the composite coating were comprehensively analyzed and contrasted with those of the traditional Ni-P coating pretreated by zinc immersion and the AAO/Ni-P coating. The outcomes indicated that the bonding strength of both the AAO/Ni-P and AAO-Cu/Ni-P coatings was notably improved compared to the traditional Ni-P coating. Unlike the AAO/Ni-P coating, the AAO-Cu/Ni-P coating displayed a significant enhancement in friction resistance due to its self-lubricating properties. Consequently, the friction coefficient was reduced by approximately 42.9 % and the volume wear decreased by 86.7 %. This research provides valuable insights into the friction and wear mechanisms of AAO-Cu/Ni-P composite coatings, offering technical support for the development of high-performance aluminum alloys.