Abrasive WearCu23307

This copper abrasive wear particle is from an oil sample collected from a 8400kVA transformer. This transformer was reportedly gas blanketed and sealed. This particle is typical of abrasive wear. The "corkscrew" shape indicates the surface was open, not in contact with another conforming surface. The bright particle to the right of the copper particles is degraded paper fiber, as can seen by the presence of the characteristic dark banding caused by depolymerization of the cellulose. The particle at the lower left is a mineral grain.