Titanium surface roughening with ultrasonic pulsating water jet

Abstract

Biomedical industries are looking for natural ways of processing biocompatible materials to improve their biological performances. One untested option is the use of the water hammer effect in the form of water droplets; this can create surfaces with high degrees of capillary elevation whose structures resemble a trabecular structure. In this study, we analyzed the modified surface morphologies and integrity of the titanium alloy Ti6Al4V using water droplet impingement generated with an ultrasonic pulsating water jet at starting frequencies of f = 20 kHz and 40 kHz. The water droplets were distributed along a linear offset trajectory. Two transition methods for producing modified surface morphologies were compared, one with a single transition and another with an additional secondary transverse transition. The created surfaces were classified according to the area surface roughness parameters, Sa and Sz. The results were compared with a control group of samples exposed to a continuous jet with ff = 0 Hz. By setting the technological parameters of an ultrasonic pulsating water jet, the aim was to create surface properties that increased biological interactions during osseointegration. The results positively support the initial indications that the pulsating water jet surface treatment was a more advantageous alternative than other techniques based on using solid particles for surface erosion, whose artifacts can become lodged in the material and contaminate surfaces.