Designed fabrication of super high hardness Ni-B-Sc nanocomposite coating for anti-wear application.

Super high hardness Ni-B-Sc coating was fabricated by electrodeposition for the first time. The effect of Sc on the structure and properties of Ni-based coating was investigated. The results show that the Ni-B-Sc coating exhibits a typical nanocomposite structure, in which the nanocrystalline Ni 2 Sc phase is embedded in the nanocrystalline Ni matrix, where nanocrystalline Ni around nanocrystallites Ni 2 Sc exhibits a fine-grained structure. The nanocomposite structure with nanoscale stiffer phase (Ni 2 Sc) embedded in the nanoscale ductile phase (Ni), significantly improve the hardness of Ni-B-Sc coating to 1484 Hv. The increased grain boundaries, phase boundaries and hard Ni 2 Sc particles cause the obvious increase in hardness as well as wear resistance of the coating. Unlabelled Image • Sc ions was firstly used as additive in the Ni electrodeposition. • The Ni-B-Sc coating exhibits a typical nanocomposite structure. • The Ni-B-Sc coatings exhibit super high hardness and excellent wear resistance. [ABSTRACT FROM AUTHOR]