Structure and tribological performance by nitrogen and oxygen plasma based ion implantation on Ti6Al4V alloy

• Published in: Applied surface science 2011-09, Vol.257 (23), p.9904-9908
• Main Authors: Feng, Xingguo, Sun, Mingren, Ma, Xinxin, Tang, Guangze
• Format: Article
• Language: English
• Subjects: Abrasive wear; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Electric potential; Exact sciences and technology; Implantation; Ion implantation; PBII; Physics; Structure; Ti6Al4V alloy; Titanium base alloys; Titanium dioxide; Tribological performance; Wear resistance; X-ray photoelectron spectroscopy
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2011.06.105

• Between the outmost layer and metallic substrate are TiO2, TiO, Ti2O3, TiN and Al2O3. • Hardness and wear resistance of the implanted layer increases with implanted voltage. • Wear rate of sample implanted N2–O2 at −50kV decreases eight times than untreated one. • Wear resistance of implanted N2–O2 is better than the same condition implanted O2. • Wear mechanism changes to ploughing wear when implanted voltage. Ti6Al4V alloy was implanted with nitrogen–oxygen mixture by using plasma based ion implantation (PBII) at pulsed voltage −10, −30 and −50kV. The implantation was up to 6×1017ions/cm2 fluence. The changes in chemical composition, structure and hardness of the modified surfaces were studied by XPS and nanoindentation measurements. According to XPS, it was found that the modified layer was predominantly TiO2, but contained small amounts of TiO, Ti2O3, TiN and Al2O3 between the outmost layer and metallic substrate. Surface hardness and wear resistance of the samples increased significantly after PBII treatment, the wear rate of the sample implanted N2–O2 mixture at −50kV decreased eight times than the untreated one. The sample implanted N2–O2 mixture showed better wear resistance than that of the sample only implanted oxygen at−50kV. The wear mechanism of untreated sample was abrasive-dominated and adhesive, and the wear scar of the sample implanted at −50kV was characterized by abrasive wear-type ploughing.