Lubricant effects in drawing coated sheets over nitride die surfaces. J.A. Schey. Lubric Engng., August 1996, 52(8), 630--636.
A drawbead simulation test is described and illustrated. It is used to study the effects of plasma nitriding of draw dies on friction, metal transfer, and surface damage. Two naphthenic mineral oils and a synthetic oil are used as lubricants and 5% concentrations of oleic acid and a borate are used as additives. Surface roughness of drawbeads and sheet materials and characteristics of the sheet materials are tabulated. Lubricant data are also shown. Tests are reported using axial, slightly cross-hatched, and circumferentially honed and polished finishes. Results show that plasma nitriding promotes the rapid development of zinc transfer layers. These are illustrated using SEM analysis. 13 refs.