A Preliminary Investigation of the Interaction of M-50 Steel with a Perfluoroalkylether Fluid and a 1 Percent Additive-Fluid Formulation.

摘要

Electron spectroscopy for chemical analysis (ESCA) has been used to characterize the passivation film formed on the surface of M-50 steel coupons during O-C testing in a perfluoroalkylether fluid containing a perfluoroalkylether aryl phosphine additive. Prior to analysis of the metal coupons, samples of the additive and fluid which had not undergone O-C testing were characterized with ESCA. The measured atom percent compositions of the fluid and additive were found to agree well with the compositions ascertained from the formulae. Freshly polished metal coupons were analyzed and were found to contain high levels of carbon and oxygen surface contamination. One coupon which had undergone O-C testing in additive-fluid formulations, surface phosphorous levels were found to be roughly five times greater than in the additive alone. This data suggests that in the protective action afforded during the O-C test, the additive has changed chemistry. (Author)