The magnetic precipitation and subsequent analysis of wear debris from a fluid sample. This approach involves passing a volume of fluid over a chemically treated microscope slide which is supported over a magnetic field. Permanent magnets are arranged in such a way as to create varying field strengths over the length of the substrate. This varying strength leads wear debris to precipitate in a distribution with respect to size and mass over the Ferro gram. Once rinsed and fixed to the substrate, this debris deposit serves as a media optical analysis of the composite wear particulates.

Tip excerpted from: The Professional's Guide to Maintenance and Reliability Terminology by Ramesh Gulati, Jerry Kahn and Robert Baldwin