The surface deterioration of a nickel-chromium-molybdenum steel under
lubricated sliding has been investigated. An electrical resistance tec
hnique has been used to aid the identification of the lubrication regi
me. The work shows that abrasive and adhesive wear mechanisms operate
under mixed lubrication to generate polished contact surfaces. Under b
oundary lubrication, delamination and abrasive wear predominate and wh
ite layers are found to develop from isolated plastically deformed zon
es beneath the sliding surface. (C) 1997 Elsevier Science S.A.