Applications of radioactive tracer technology in the real-time measurement of wear and corrosion

Radioactive tracer technology has been used for many years as a tool to make highly sensitive real-time measurements of wear and corrosion. With this technique, the material of interest is tagged with radioactive isotopes through either direct activation of a relatively small number of atoms in the component itself, or implantation of radioactive isotopes. As the component wears or corrodes under test, radioactive atoms are transported from the surface in the form of wear particles or corrosion products. Wear or corrosion is measured in real-time through either interrogation of the buildup of radioactivity in the transport fluid, or by the reduction in activity of the labeled wear component. The process involves selection of an appropriate labeling technique, labeling of a component or components of interest, calibration, testing and data reduction and analysis. Although the majority of the work performed has been in the automotive engine and lubricant industry, Southwest Research Institute® has recently extended the application into other fields, such as hydraulic pump wear, prosthetic hip joint wear, wear in marine engines and crude oil corrosivity. This paper discusses the various techniques employed to label components of interest, the advantages of the techniques, and gives several examples of current applications of this technology.