Lecture No.175

Title: Composite porous coating for bioactive titanium-based orthopedic implants via cold spraying
Speaker: Dr.Dong Qiu, Vice Chancellor’s Senior Research Fellow, School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University
Date/Time: 2016-01-15,10:00-11:00am
Venue: Room 308,Material Building 308
Invitor: Deliang Zhang
   Dr Qiu was awarded a PhD degree majored in materials science and engineering in 2005 from Tsinghua University. He had been working as a Postdoctoral Research Fellow, and then Australian Research Fellow at the University of Queensland from 2005 to 2014. Dr Qiu joined RMIT University in 2015 as a Vice Chancellor’s Senior Research Fellow, focusing on the microstructure design for additively manufactured metal components. In the last 10 years, his research has spanned a range of areas, such as grain refinement of cast alloys, crystallography in solid-solid phase transformations and surface modification of biomedical implants. His contribution to the research community is witnessed by more than 50 peer-reviewed journal papers, with 16 out of these published in Acta Materialia, the best journal in the field of physical metallurgy worldwide. His publications have been cited by more than 600 times and his H-index is 16 in Scopus. He has also succeeded in obtaining 11 competitive grants in the last ten years, including 3 under ARC DP scheme and 3 under ARC LEAF scheme.
   Surface modification of titanium-based implants is considered a highly effective solution to enhance osseointegration. This study describes a novel Ti/hydroxyapatite (HA) composite porous coating produced using a cold spraying technique followed by alkaline leaching and sintering. Experimental results indicate desirable open-cell structure with 50–150 mm pore size and 60–65% macroporosity. In particular, the reinforced HA particles are exposed to the surface of the coating resulting in enhanced mineralization ability in simulated body fluid. None of the coatings displayed a cytotoxic response in SaOS-2 cells cultured in vitro for up to 48 h. The bond strength between the porous coating and the Ti substrate was found to be 20 MPa. These properties are comparative to or better than products currently on the market and thus this novel coating has potential use in orthopedics.

Location:Room 308,Material Building A