A parametric study of ultra-short laser surface patterning of freeze foamed TCP-Zr: Effects of laser parameters on surface morphology

The application of ultra-short lasers pulses in surface modification has gained a significant interest as they allow precise patterning of materials without inducing any collateral thermal damages. Tricalcium phosphate (TCP) is a widely exploited material for scaffolds in bone tissue engineering; however, such composites could lack the appropriate porosity that is crucial for the tissue regeneration process. This article presents a combination of fabricating porous ceramic scaffolds and their processing by a femtosecond (fs) laser for enhancement of the surface properties. The morphological observation revealed evident differences on the exterior of the treated zones, as the dense structure was preserved but the porosity of the surface appeared improved. An X-ray diffraction analysis showed that the laser treatment increased the crystallinity of ZrO₂ and TCP, thus stabilizing the material. The laser-induced surface microporosity substantially changed the wetting state of the scaffolds' surfaces making them hydrophilic. Based on these findings, we could state that the femtosecond laser processing of TCP-ZrO₂ composites could have the potential to improve their applications in fields such as bone tissue engineering.