Porous ceramic coating formed on 316L by laser cladding combined plasma electrolytic oxidation for biomedical application
(1. College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014, China;
2. Institute of Laser Advanced Manufacturing, Zhejiang University of Technology, Hangzhou 310014, China;
3. Collaborative Innovation Center of High-end Laser Manufacturing Equipment, Zhejiang University of Technology, Hangzhou 310014, China;
4. Laser Technology Research Institute, National Technical University of Ukraine “Kiev Polytechnic Institute”, Kiev, 03056, Ukraine)
2. Institute of Laser Advanced Manufacturing, Zhejiang University of Technology, Hangzhou 310014, China;
3. Collaborative Innovation Center of High-end Laser Manufacturing Equipment, Zhejiang University of Technology, Hangzhou 310014, China;
4. Laser Technology Research Institute, National Technical University of Ukraine “Kiev Polytechnic Institute”, Kiev, 03056, Ukraine)
Abstract: In order to improve the bioactivity of 316L stainless steel, a titanium layer was prepared on the surface of 316L by laser cladding (LC), followed by plasma electrolytic oxidation (PEO) to form a porous ceramic coating on titanium layer. The morphologies, microstructure and compositions of the coated samples were characterized by 3D surface profiler, SEM, EDS, XRD and XPS. The corrosion resistance and bioactivity of the coatings were evaluated by potentiodynamic polarization and immersion test in simulated body fluid (SBF), respectively. The results showed that the porous ceramic coating mainly consisted of anatase and rutile, and highly crystalline HA was also detected. The main elements of the PEO coating are Ca, P, Ti and O. The LC+PEO composite bio-coating has more excellent corrosion resistance than the 316L substrate in simulated body fluid. Furthermore, the composite coating could effectively improve the bioactivity of 316L stainless steel.
Key words: 316L stainless steel; laser cladding; titanium; plasma electrolytic oxidation; bioactivity