Corrosion fatigue characteristics of total hip prosthesis in simulated body fluid

Objective of this study is to perform fatigue testing of the total joint replacements made of316L stainless steel to validate the safety of the component before the clinical use. Thompsonhip prosthesis was tested by using double cantilever beams bending machine designed andmanufactured at Department of Metallurgical and Materials Science Engineering. Thephysiological environment, namely the body fluid, can be very corrosive for implantmaterials. In order to ensure the safety of a hip prosthesis against corrosion fatigue failure,fatigue tests must be performed in a corrosive medium with low frequency load application.Component fatigue tests were therefore performed in Ringer?s solution (0.9% NaCl) at afrequency of 10 Hz in accordance with ISO 7206/4 standard. At this rate, a single hip stemfatigue test requires 11.5 days of continuous testing without any failure for a numbers of 107cycles.The objective of this study was also to perform the fatigue test of the Thompson hipprosthesis in accordance with ISO 7206/4, evaluate the real stresses by using the strain gauge,and to determine the fatigue life of prosthesis. The purpose of this study was also to comparethe real stresses measured at different location of prosthesis by means of strain gauges withthe distributions of theoretical stresses calculated by CAD modelling.