Experimental biocompatibility investigations of Ti–6Al–7Nb alloy in micromilling operation in terms of corrosion behavior and surface characteristics study

Abstract

Titanium (Ti)-based alloy is extensively used in the biomedical field due to its properties that promote osseointegration. The present work deals with an experimental study on the effect of microcutting of Ti–6Al–7Nb on corrosion resistance and surface characteristics for enhanced biocompatibility. Experiments were carried out by using Taguchi L9 orthogonal array with process variables include cutting speed (vc), feed per tooth (fz), and depth of cut (ap). Microslot of size 700 µm for a length of 10 mm was made using high-speed micromachining station under wet condition. Surface morphology study was carried out using a scanning electron microscope and the inference was made. It is inferred that lower vc of 31.4 m/min and higher ap condition of 200 μm yield more microparticle adhesion and burr formation. At higher vc, minimum defects were found which results in fine surface finish. Potentiostat setup was used for corrosion resistance measurement, and corresponding Icorr values were obtained from potentiodynamic polarization curve. Icorr values are found as minimum at higher vc and lower ap conditions. Changes in surface characteristics are analyzed after corrosion study. It is observed that at higher vc and lower ap conditions, Ti–6Al–7Nb alloy exhibits higher corrosion resistance under in vitro condition that can promote osseointegration.