TITLE:
Dependence of Nanotextured Titanium Orthopedic Surfaces on Electrolyte Condition
AUTHORS:
Sachin M. Bhosle, Radheshyam Tewari, Craig R. Friedrich
KEYWORDS:
Implants, Anodization, TiO2 Nanotubes, Fluoride Concentration, Titanium
JOURNAL NAME:
Journal of Surface Engineered Materials and Advanced Technology,
Vol.6 No.4,
October
12,
2016
ABSTRACT: Electrochemical etching of titanium alloy in a fluoride-containing electrolyte results in ordered nanotextured surfaces. The reproducibility of nanotextured surfaces depends on several process parameters, most notably the fluoride ion concentration in the electrolyte. In the present work, electrochemical etching of Ti6Al4V alloy foils in ethylene glycol containing 0.66 wt% NH4F and 2% deionized water was carried out at 60 V for 45 minutes. This paper describes the depletion of fluoride ion concentration and contamination of electrolyte upon reuse. Inductively coupled plasma-optical emission spectroscopy was used to measure the dissolution of metal oxides in the electrolyte during etching. We found increasing concentration of the alloy elements Ti, Al, V contaminated the electrolyte due to repeated reuse of the electrolyte. The results show an appreciable log-linear depletion of fluoride ion concentration resulting in a changed surface morphology, chemical composition and etched volume. This paper provides an important insight to changes in surface morphology and surface chemistry with extended reuse of the etching electrolyte, useful for regulatory approvals.