Laser surface texturing of Ti-6Al-4V and controlled oxide formation for improving biocompatibility

Abstract

This paper reports the results of surface modification of Ti-6Al-4V using a 75 W Q-switched Nd:YAG (λ=1064 nm, τ=100 ns) laser in air with the ultimate aim of improving osseointegration and biocompatibility. Melting and rapid re-solidification develop new textures which mainly include molten, re-solidified droplets.Two types of samples were used. The first set of experiments was performed on samples with machined and polished surfaces. For the second set of samples a layer of oxide was formed on the laser treated surfaces. Oxide film growth was effected by laser heating in air. Analysis of the surface finish was done by XRD, SEM and surface roughness testing.The effects of process parameters (laser power, frequency, and scan speed) on surface finish are discussed. Surface finish is correlated with estimates of temperatures using simple analytical heat-transfer models.To evaluate the biocompatibility, contact angle measurement and SBF test were carried out. The effect of laser surface treatment and further oxide growth were discussed on the contact angle and formation of Ca and P-containing crystals on the surface.This paper reports the results of surface modification of Ti-6Al-4V using a 75 W Q-switched Nd:YAG (λ=1064 nm, τ=100 ns) laser in air with the ultimate aim of improving osseointegration and biocompatibility. Melting and rapid re-solidification develop new textures which mainly include molten, re-solidified droplets.Two types of samples were used. The first set of experiments was performed on samples with machined and polished surfaces. For the second set of samples a layer of oxide was formed on the laser treated surfaces. Oxide film growth was effected by laser heating in air. Analysis of the surface finish was done by XRD, SEM and surface roughness testing.The effects of process parameters (laser power, frequency, and scan speed) on surface finish are discussed. Surface finish is correlated with estimates of temperatures using simple analytical heat-transfer models.To evaluate the biocompatibility, contact angle measurement and SBF test were carried out. The effect of laser surface treatment and further...