Mechanism of tribofilm formation on Ti6Al4V oxygen diffusion layer in a simulated body fluid

R Yazdi; H M Ghasemi; M Abedini; C Wang; A Neville

doi:10.1016/j.jmbbm.2017.10.020

Mechanism of tribofilm formation on Ti6Al4V oxygen diffusion layer in a simulated body fluid

J Mech Behav Biomed Mater. 2018 Jan:77:660-670. doi: 10.1016/j.jmbbm.2017.10.020. Epub 2017 Oct 18.

Authors

R Yazdi¹, H M Ghasemi², M Abedini³, C Wang⁴, A Neville⁴

Affiliations

¹ School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, Iran.
² School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, Iran. Electronic address: hghasemi@ut.ac.ir.
³ Department of Metallurgy and Materials Engineering, Faculty of Engineering, University of Kashan, Kashan, Iran.
⁴ Institute of Functional Surfaces, School of Mechanical Engineering, University of Leeds, Leeds LS2 9JT, UK.

PMID: 29102891
DOI: 10.1016/j.jmbbm.2017.10.020

Abstract

An Oxygen Diffusion Layer (ODL) was generated on the surface of Ti6Al4V alloy by thermal oxidation treatment. In vitro tests for cytotoxicity were performed in the presence of Ti6Al4V and the ODL samples with the culture of G292 Cells using MTT assay. The results showed a similar cell viability in the presence of the both samples. Wear behaviour of Ti6Al4V and the ODL samples was investigated in a phosphate buffered saline solution under a normal load of 30N at a sliding velocity of 0.1m/s. The worn surface and subsurface of the samples were studied using SEM, STEM, TEM, XPS, AFM, nano-hardness and surface profilometry. A bio-tribofilm was observed on the worn surface of the ODL. TEM studies showed that the tribofilm had an amorphous structure and contained oxygen and phosphorous as confirmed by XPS and EDS analysis. AFM images also revealed that the tribofilm consisted of compacted fine debris. The formation of the tribofilm on the ODL with higher hardness and strength resulted in a decrease of about 95% in the wear rate compared with Ti6Al4V alloy.

Keywords: Bio-tribofilm; Oxygen Diffusion Layer; TEM; Ti6Al4V; XPS.

MeSH terms

Alloys / chemistry
Biocompatible Materials / chemistry*
Body Fluids*
Cell Line
Cell Survival
Diffusion
Hardness
Humans
Materials Testing
Microscopy, Atomic Force
Microscopy, Electron, Scanning
Microscopy, Electron, Transmission
Nanostructures / chemistry
Osteoblasts / metabolism
Oxidation-Reduction
Oxygen / chemistry*
Phosphorus / chemistry
Plastics
Stress, Mechanical
Surface Properties
Temperature
Titanium / chemistry*

Substances

Alloys
Biocompatible Materials
Plastics
titanium alloy (TiAl6V4)
Phosphorus
Titanium
Oxygen