scholarly journals Amorphous Carbon Coatings for Total Knee Replacements—Part I: Deposition, Cytocompatibility, Chemical and Mechanical Properties

Polymers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1952
Author(s):  
Benedict Rothammer ◽  
Kevin Neusser ◽  
Max Marian ◽  
Marcel Bartz ◽  
Sebastian Krauß ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Amorphous Carbon ◽  
Detailed Characterization ◽  
Carbon Coatings ◽  
Dlc Coatings ◽  
Total Knee Replacements ◽  
Knee Replacements ◽  
Total Knee ◽  
Amorphous Carbon Coatings

Diamond-like carbon (DLC) coatings have the potential to reduce implant wear and thus to contribute to avoiding premature failure and increase service life of total knee replacements (TKAs). This two-part study addresses the development of such coatings for ultrahigh molecular weight polyethylene (UHMWPE) tibial inlays as well as cobalt–chromium–molybdenum (CoCr) and titanium (Ti64) alloy femoral components. While a detailed characterization of the tribological behavior is the subject of part II, part I focusses on the deposition of pure (a‑C:H) and tungsten-doped hydrogen-containing amorphous carbon coatings (a‑C:H:W) and the detailed characterization of their chemical, cytological, mechanical and adhesion behavior. The coatings are fabricated by physical vapor deposition (PVD) and display typical DLC morphology and composition, as verified by focused ion beam scanning electron microscopy and Raman spectroscopy. Their roughness is higher than that of the plain substrates. Initial screening with contact angle and surface tension as well as in vitro testing by indirect and direct application indicate favorable cytocompatibility. The DLC coatings feature excellent mechanical properties with a substantial enhancement of indentation hardness and elastic modulus ratios. The adhesion of the coatings as determined in modified scratch tests can be considered as sufficient for the use in TKAs.

scholarly journals Amorphous Carbon Coatings for Total Knee Replacements—Part II: Tribological Behavior

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1880 ◽  
Author(s):  
Benedict Rothammer ◽  
Max Marian ◽  
Kevin Neusser ◽  
Marcel Bartz ◽  
Thomas Böhm ◽  
...  
Keyword(s):  
Amorphous Carbon ◽  
Laser Scanning ◽  
Tribological Behavior ◽  
Wear Behavior ◽  
Laser Scanning Microscopy ◽  
Adhesion Properties ◽  
Carbon Coatings ◽  
Knee Replacements ◽  
Total Knee ◽  
Amorphous Carbon Coatings

Diamond-like carbon coatings may decrease implant wear, therefore, they are helping to reduce aseptic loosening and increase service life of total knee arthroplasties (TKAs). This two-part study addresses the development of such coatings for ultrahigh molecular weight polyethylene (UHMWPE) tibial inlays as well as cobalt-chromium-molybdenum (CoCr) and titanium (Ti64) alloy femoral components. While the deposition of a pure (a-C:H) and tungsten-doped hydrogen-containing amorphous carbon coating (a-C:H:W) as well as the detailed characterization of mechanical and adhesion properties were the subject of Part I, the tribological behavior is studied in Part II. Pin-on-disk tests are performed under artificial synovial fluid lubrication. Numerical elastohydrodynamic lubrication modeling is used to show the representability of contact conditions for TKAs and to assess the influence of coatings on lubrication conditions. The wear behavior is characterized by means of light and laser scanning microscopy, Raman spectroscopy, scanning electron microscopy and particle analyses. Although the coating leads to an increase in friction due to the considerably higher roughness, especially the UHMWPE wear is significantly reduced up to a factor of 49% (CoCr) and 77% (Ti64). Thereby, the coating shows continuous wear and no sudden failure or spallation of larger wear particles. This demonstrated the great potential of amorphous carbon coatings for knee replacements.

Structure and mechanical properties of Ni and Cr binary doped amorphous carbon coatings deposited by magnetron sputtering and pulse cathodic arc

2020 ◽  
Vol 701 ◽  
pp. 137942
Author(s):  
Bingbing Zhou ◽  
D.G. Piliptsou ◽  
Xiaohong Jiang ◽  
A.V. Rogachev ◽  
A.S. Rudenkov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Magnetron Sputtering ◽  
Amorphous Carbon ◽  
Carbon Coatings ◽  
Amorphous Carbon Coatings ◽  
Cathodic Arc

Combined influences of mechanical properties and surface roughness on the tribological properties of amorphous carbon coatings

Wear ◽  
2006 ◽  
Vol 260 (1-2) ◽  
pp. 62-74 ◽  
Author(s):  
Naoki Fujisawa ◽  
David R. McKenzie ◽  
Natalie L. James ◽  
John C. Woodard ◽  
Michael V. Swain
Keyword(s):  
Mechanical Properties ◽  
Surface Roughness ◽  
Amorphous Carbon ◽  
Tribological Properties ◽  
Carbon Coatings ◽  
Amorphous Carbon Coatings

Micro/nanomechanical and tribological characterization of ultrathin amorphous carbon coatings

1999 ◽  
Vol 14 (6) ◽  
pp. 2328-2337 ◽  
Author(s):  
Xiaodong Li ◽  
Bharat Bhushan
Keyword(s):  
Wear Resistance ◽  
Amorphous Carbon ◽  
Carrying Capacity ◽  
Load Carrying Capacity ◽  
Carbon Coatings ◽  
Load Carrying ◽  
Tribological Characterization ◽  
Thick Coatings ◽  
Amorphous Carbon Coatings

Micro/nanomechanical and tribological characterization of ultrathin amorphous carbon coatings, deposited by filtered cathodic arc (FCA), direct ion beam (IB), electron cyclotron resonance plasma chemical vapor deposition (ECR-CVD), and sputter (SP) deposition processes on Si substrate have been conducted using a nanoindenter with a nanoscratch attachment and an accelerated ball-on-flat tribometer. Coating thicknesses of 20, 10, 5 nm and, for the first time, 3.5 nm coatings have been investigated. It was found the FCA coating exhibits the highest hardness and elastic modulus, followed by the ECR-CVD, IB, and SP coatings. In general, the thicker coatings exhibited better scratch/wear performance than the thinner coatings due to their better load-carrying capacity as compared to the thinner coatings. At 20 nm, the FCA and ECR-CVD coatings show the best scratch and wear resistance, while the IB and ECR-CVD coatings show the best scratch and wear resistance at 10 nm. Five nanometer thick coatings show reasonable scratch and wear resistance, while 3.5 nm thick coatings show extremely low load-carrying capacity and poor scratch and wear resistance. It appears that the 3.5 nm coatings studied are unfeasible for scratch and wear resistance applications as of now.

Sign in / Sign up

Export Citation Format

Share Document