Problem: Three metallic particulates were recovered from a system, drawing oil from a common lubrication source.
Discussion: Deep, primarily parallel scoring marks were observed on the surface of all three of the particulates. The metallurgy, tempering and other factors relating to two of the samples appeared to indicate that these are comprised of mild steel.
In the case of one of the samples, a further scan of the "wire" portion of the sample detected the presence of stainless steel, with the hematite formations around the wire are therefore likely to be the result of corrosion of the non-stainless steel beneath caused my moisture held beneath the wire.
The metallurgy the third sample was somewhat different, and appeared to be 304 grade stainless steel based on the concentration of alloying metal, with a near-perfect fit for relative Nickel and Chromium content, ultimately enabling the identification of its source.
Solution: The prevalent wear mode for the three steel particles was determined to commonly be sliding wear, typically indicative of the breakdown of lubricating films in a system, either by lubricant starvation or degradation. Where the metallurgy had uncovered the particulate source, immediate inspections and repairs were implemented where necessary. A detailed review of the current lubrication program on site subsequently followed.