Indentation and scratch testing of DLC-Zr coatings on ultrafine-grained titanium processed by high-pressure torsion

• Autor(a) principal: Wang, Chuan Ting
• Data de Publicação: 2013
• Outros Autores: Escudeiro, Ana, Polcar, Tomas, Cavaleiro, Albano, Wood, Robert J. K., Gao, Nong, Langdon, Terence G.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10316/27171; https://doi.org/10.1016/j.wear.2012.12.033
• topic: High-pressure torsion; Titanium; DLC-Zr coatings; Adhesion; Bio-implants

High-pressure torsion was employed to refine the microstructure of grade 2 Ti under an imposed pressure of 3.0 GPa at room temperature. The microhardness of grade 2 Ti increased from 1.82 GPa for the coarse grain state to 3.05 GPa after high-pressure torsion processing, where this value is very close to the hardness of the Ti–6Al–4V alloy. Subsequently, several diamond-like carbon (DLC) coatings with thicknesses of ∼1.4 μm were deposited on as-received Ti, high-pressure torsion processed Ti and Ti–6Al–4V samples via physical vapour deposition. Both indentation and scratch tests showed a much improved adhesion of DLC-7Zr, DLC:H-7Zr and DLC-9Zr coatings with high-pressure torsion processed Ti as the substrate by comparison with the same coatings on coarse-grained Ti. The results suggest that commercial pure Ti processed by high-pressure torsion and coated with a diamond-like carbon coating provides a potential candidate material for bio-implant applications.