Title :
Residual stress in hydroxyapatite coating: nonlinear analysis and high-energy synchrotron measurements
Author :
Fogarassy, Paul ; Cofino, Bruno ; Millet, Pierre ; Lodini, Alain
Author_Institution :
Univ. de Reims Champagne-Ardenne, France
fDate :
7/1/2005 12:00:00 AM
Abstract :
The thermal deposition of hydroxyapatite (HA) on titanium alloy substrate (Ti-6Al-4V) leads to a structure that has very good osseointegration properties. However, clinical failures have been occasionally reported at the interface between substrate and coating. Lifetime is the main parameter in such prostheses; therefore, in order to improve their quality, it is necessary to evaluate the level of stresses near the interface. The high-energy synchrotron radiation combines the advantages of a bulk analysis and reduced volume of the gauge. The objective of our study was to calculate the residual stress using a nonlinear finite-element model and to measure residual stress level near the interface, in the hydroxyapatite coating and in titanium alloy substrate with a nondestructive and high-resolution experiment. The high-energy synchrotron radiation of the BM16 beam-line at ESRF (Grenoble-France) was used with a resolution of down to 10 micrometers. The experimental measurements validate the results found by means of nonlinear finite-element analysis of the plasma spraying induced stress.
Keywords :
X-ray diffraction; aluminium alloys; bioceramics; biomechanics; calcium compounds; finite element analysis; internal stresses; plasma arc sprayed coatings; prosthetics; titanium alloys; vanadium alloys; Ca/sub 10/PO/sub 4/OH; TiAlV; clinical failures; high-energy synchrotron measurements; hydroxyapatite coating; nonlinear finite-element model; osseointegration properties; plasma spraying induced stress; prostheses; residual stress; Coatings; Finite element methods; Lead; Plasma measurements; Prosthetics; Residual stresses; Stress measurement; Synchrotron radiation; Thermal spraying; Titanium alloys; Finite-element analysis; hydroxyapatite; interface; residual stresses; synchrotron diffraction; Adsorption; Coated Materials, Biocompatible; Computer Simulation; Durapatite; Elasticity; Materials Testing; Models, Chemical; Nonlinear Dynamics; Stress, Mechanical; Surface Properties; Synchrotrons; Titanium; X-Ray Diffraction;
Journal_Title :
Biomedical Engineering, IEEE Transactions on
DOI :
10.1109/TBME.2005.847526