Product Code: ICAL05_M604

Laser Surface Texturing of Ti-6Al-4V and Controlled Oxide Formation for Improving Biocompatibility
Authors:
Nazanin Mirhosseini, The University of Manchester; Manchester UK
Marc Schmidt, The University of Manchester; Manchester UK
Philip Crouse, The University of Manchester; Manchester UK
Lin Li, The University of Manchester; Manchester UK
Mustapha Soufian, Gesco; Manchester UK
Presented at ICALEO 2005

This paper reports the results of surface modification of Ti-6Al-4V using a 75 W Q-switched Nd:YAG ( ?=1064 nm, t=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 (diameter 5-60 m) and ring shaped features (outer diameter 45-80 m and inner diameter 20-40 m) on the surface.
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 first formed on the machined and polished surfaces. Oxide film growth was effected by laser heating in air. Analysis of the surface finish was done by SEM and surface roughness testing. The fluence thresholds for melting and evaporation are reported. The effects of process parameters (laser power, frequency, and scan speed) on surface finish are discussed. Surface finish is correlated with estimates of melt pool geometry and temperatures using simple analytical heat-transfer models. The effects of the process on the underlying metal substrate are detailed.