Preliminary examinations of mechanical properties of DLC and novel DLC-polymer hybrid coatings for resurfacing hip prostheses
|Emilia Choińska 1, Maciej M. Spychalski 1, Wojciech Swieszkowski 1, Ingrid Milosev 2, Veli M. Tiainen 3, Krzysztof J. Kurzydlowski 1|
1. Warsaw University of Technology, Faculty of Materials Science and Engineering (InMat), Wołoska 141, Warszawa 02-507, Poland
Resurfacing hip implants are promising type of hip implants, since they allows maximum preservation of the patient’s own bone. This speeds up the healing process and facilitates eventual later revision surgery. But there are some problems with metallic wear debris, which induce metallosis. They can also lead to aseptic loosening of the implant.
The diamond-like carbon (DLC) and novel DLC-polymer hybrid (DLC-p-h) nanocomposite coatings, deposited with filtered pulsed arc discharge method (FPAD), have the potential to improve greatly the tribological properties of these implants by decreasing the friction and wear.
The aim of the present study was preliminary examinations of the DLC and DLC-p-h anti-wear coatings deposited on AISI316L stainless steel. The different composition of cathodes and parameters of FPAD process were used to fabricate the 3 types of coatings: DLC, DLC-PDMS-h and DLC-PTFE-h. These deposited coatings were investigated in terms of surface characterization, chemical composition, mechanical and electrochemical properties, using optical profilometer, SEM, FIB, nanoindenter Hysitron, XPS, Raman spectroscopy and electrochemical methods.
The results show that coatings deposited with FPAD method are homogenous and good quality. The two types of novel coatings has similar mechanical properties (Er = 5-13GPa, H=0,2-0,7GPa), which are different (much lower) than for DLC (Er = 200-230GPa, H=21,6-22,3GPa). Further examination will be focus on the tribological properties of novel hybrid coatings.
The deposited coatings offer a good corrosion protection under physiological conditions, as investigated by electrochemical potentiodynamic measurement in Hank’s simulated physiological solution at 37ºC. The corrosion resistance deduced from polarization resistance measurements increases in the following order: DLC<DLC-PTFE-h and DLC-PDMS-h.
Presentation: Poster at E-MRS Fall Meeting 2008, Symposium L, by Emilia Choińska
See On-line Journal of E-MRS Fall Meeting 2008
Submitted: 2008-07-01 17:46 Revised: 2009-06-07 00:48