The Gilbert Biomaterials and Regenerative Medicine Laboratory

RESEARCH: TRIBOCORROSION MODELING, TESTING AND ANALYSIS

Tribocorrosion Modeling, Testing and Analysis

The Gilbert Lab has been exploring mechanically assisted corrosion processes for over 25 years. These studies have spanned the range from implant retrieval analysis, implant performance test studies and fundamental studies of oxide film disruption and repassivation.

This latter area has included development of a precision fretting corrosion test system and analysis method, development a comprehensive model of fretting corrosion that includes contact mechanics, oxide film growth physics and chemistry, and impedance-based voltage-current correlation methods to predict current and voltage transients resulting from tribocorrosion processes.

In addition, these fretting corrosion test systems have been modified to incorporate cell culture methods to analyze interactions between living systems and fretting alloy surfaces.

Fretting Corrosion Modeling
Contact mechanics and oxide film repassivation
The basic concept related to fretting corrosion of metallic biomaterials is the oxide disruption and repassivation process. This model incorporates the surface mechanics associated with asperity-asperity contact and plasticity-based disruption of oxide films. It also includes the electrochemical processes associated with oxide film repassivation which is an oxidation reaction that takes metal atoms on the disrupted surface and reacts them with water to form oxide, hydrogen ions and electrons. The currents associated with electron generation are then used as a direct measure of the corrosion process. This model also incorporates the high-field oxide film growth model proposed by Cabrerra and Mott, and Gunter Schulze and Betz to yield a linear dependence of the oxide film thickness to the potential established across the interface by the reactions.

Finally, Duhamel integrals (heredity intergrals) are used to relate mechanical disruption to current and voltage transients (Gilbert et al, STMP, 2016).


Figure: Underlying asperity-asperity contact interactions that result in the generation of fretting corrosion currents (Swaminathan and Gilbert, Biomat, 2012)


Figure: Plasticity-based fretting corrosion currents based on oxide film properties.


Figure: Heredity (Duhamel) integral approach to determining fretting currents based on oxide film volume abrasion-repassivation.


Figure: Heredity (Duhamel) integral approach to predicting the voltage-time behavior of an electrode undergoing tribocorrosion processes based on electrode impedance analysis.

References:
Swaminathan V, Gilbert JL, “Fretting Corrosion of CoCrMo and Ti6Al4V Interfaces”, Biomaterials, 33 (2012), 5487-5503.

Swaminathan V, Gilbert JL, “Potential and Frequency Effects on Fretting Corrosion of Ti6Al4V and CoCrMo Surfaces”, J Biomed Mat Res – Part A, (2013) 101A(9):2602-2612.

Gilbert JL, Mali SA, Liu Y, “Area-Dependent Impedance Based Voltage Shifts During Tribocorrosion of Ti-6Al-4V Biomaterials: Theory and Experiment”, IOP Surface Topography: Metrology and Properties, Special Topic Issue: Surfaces and interfaces in bioengineering systems”, May, 4 (2016) 034002, pp 1-18.

Kubacki GM, Hui T, Gilbert JL, Voltage and Wear Debris from Ti-6Al-4V Interact to Affect Cell Viability During In-Vitro Fretting Corrosion”, J Biomed Mat Res – Part A, August 2017, DOI: 10.1002/jbm.a.36220.

Liu Y, Gilbert JL, “The effect of simulated inflammatory conditions and pH on fretting corrosion of CoCrMo alloy surfaces”, Wear, Vol. 390–391, 15 November 2017, pp 302-311.

Ouellette ES, Gilbert JL, “Properties and Corrosion Performance of Self-Reinforced Composite PEEK for use as Modular Taper Gaskets”, Clin Ortho and Rel Res, Nov. 2016, Vol. 474, (11), pp 2414-2427.