Baghdadite ceramic (BAG: Ca3ZrSi2O9) in its bulk form has the potential of supporting osteoblast cell adhesion and proliferation, while showing enhanced mechanical properties compared to hydroxyapatite (HAp: Ca10(PO4)6(OH)2). Mr Pham presented how this work explores the use of Baghdadite powders as feedstock for the atmospheric plasma spray (APS) process to manufacture biomaterials coatings onto Ti-6Al-4V substrates. The paper compares the microstructure and mechanical properties between BAG and HAp coatings. More consistent surface and bulk features are found for the BAG coating. The BAG coating reveals greater Vickers microhardness results compared to HAp coating (BAG: 325.5 ± 55.2 HV300 and HAp: 118.3 ± 21.2 HV300). Although BAG coatings show a lower level of crystallinity compared to the HAp coating; both nanohardness and elastic moduli results for the nanoindentation tests indicate that the BAG coating presents enhanced mechanical properties compared to the HAp coating. The distributions of mechanical properties including hardness and moduli indicate a more homogeneous microstructure for the BAG coating. BAG coating presents better wear resistance than HAp coating with regards to nanoscratch and scanning wear tests. The results indicate that APS of BAG is a candidate coating for orthopedic implants in load bearing applications.
Duy Quang Pham is a PhD candidate with Swinburne University of Technology. His thesis topic is Bioactive ceramic coatings with antimicrobial properties to increase orthopaedic implant longevity, and is being supervised by Distinguished Professor Chris Berndt (Swinburne) and Dr Andrew Ang (Swinburne). His thesis focuses on the short lifespan of orthopaedic implants as a major clinical problem, where failure often occurs within a few months because of infection, or within 10–15 years due to loosening.
19 July 2019