Corrosion equipment for fatigue testing of bioresorbable magnesium alloys

Currently, there is no generally accepted standard setup for measurements the fatigue limits of biomedical magnesium alloy samples in corrosive environments. Usually every research group uses assemble its own testing system, which does not always take into account many technical factors that significantly affect the final result of the experiment. In this paper, we propose a setup that can be assembled on the basis of a standard fatigue machine for measurements the corrosion-fatigue durability of bioresorbable magnesium alloys in various physiological solutions. It’s main components include: a testing machine with a slot plate required for rigid attachment of the chamber; polyamide grips providing galvanic isolation; a peristaltic pump for pumping the medical solution used; an ionometer connected to a computer to record changes in pH and temperature; a thermostat to maintain the temperature in the chamber within a given range; an additional solution fed into the chamber through a needle using a small peristaltic pump when a given pH level is exceeded, which allows maintaining the pH within the acceptable range of values. The setup uses corset-type samples, although other options are also acceptable, and provides the ability to install a camera to visualize corrosion processes on witness samples. The test system allows achieving good repeatability and reliability of the obtained results, which was experimentally verified and confirmed on magnesium alloy MA14 of different melts, selected as a model. The proposed setup can be used to assess the fatigue life of magnesium alloys for medical purposes. It is not difficult to implement in ordinary factory laboratory conditions.