LAUSR

Abstract For increasing the interfacial bonding of Ni deposits onto Ti surface, the objectives of this work are to explore an effective approach for LaCl3-modified Ni nanocrystals on porous surface of Ti substrate. Three-dimensional (3D) heterotypic nanopores were well organized with a diameter size of ~300 nm through surface anodizing in H3PO4-containing acid solution at DC 180 V. In view of the above considerations, the anodized surface with a 3D-open reticular structure was processed of high adsorption capacity leading into pitting growth of Ni crystals into 3D-pores. Experimental data have referred that a leaf-like surface with the diversified orientations of Ni (111) (200) (220) (311) facets were conducted for Ni-LaCl3 deposits instead of an exclusive growth of Ni (111) (200) facets for pure Ni. Based on Nanoindentation tests, it exhibited the ratio of micro hardness (H3) and elastic modulus (E2) of Ni samples remarkably increased with increasing LaCl3 addition from 0 to 2.0 g/L. As excepted, the steady-state friction coefficient was ~0.28 for Ni-2.0 g/L LaCl3 composites, which was about one order of magnitude lower than that of pure Ni sample during oxidized at 500 °C in air. The exceptional improvements of corrosion resistance for LaCl3-modified Ni deposits were associated with the co-existence of high adsorptive La3+ ions and the La-rich insoluble corrosive products in 1 M (mol/L) HCl solution. In light of this, Ni-based nanocomposites on 3D-heterotypic porous surface of Ti alloys would provide an effective guidance for protecting Ti alloys against wear and corrosive damages.